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Physical Environment as an Influence on Health -  CT

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Physical Environment as an Influence on Health -  CT

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The physical environment has a major influence on health through air pollution, toxic sites, healthy, and unhealthy food. Many of these aspects may cause the human body to not function correctly and causes people discomfort. Other aspects may help the body function better than normal and provide lots of energy.

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People tend to forget we live in a physical environment that can influence health. Human beings spend more than 88 percent of their lives inside built environments where they live, work and play. The problem is that building materials such as furniture, fabrics, window treatments, carpeting - or no carpeting - and mechanical systems, such as heating and air conditioning (HVAC) systems, can all influence our health.

That's why our theme for this year's St. David's Center for Health Promotion and Disease Prevention Research in Underserved Populations (CHPR) conference is "The Physical Environment's Influences on Health" and will focus on the influences that our physical or built environment has on our health and how these could be altered for the better. This "health in all policies" approach underscores how all sectors of civil society make decisions that impact health on a population level.

Because so much of our environment is designed by humans and, therefore, somewhat under human control, it is essential that we understand the impact it makes on our health and well-being. The way cities and neighborhoods are designed can either promote or hinder how we engage in health-promoting activities.

Conference speakers and panelists hail from a wide variety of disciplines and backgrounds, such as nursing (environmental/occupational health), medicine (population health), public health (community environments), architecture (community and regional planning), communication (environmental risk), and engineering (indoor air quality and materials emissions from the built environment). They will take us through the negative health outcomes that can arise due to environmental factors and identify strategies we can adopt to reduce, control or eliminate the source of any negative factors.

This year's conference has been shortened to a half-day, and the format has changed from serial speakers to one keynote speaker and a moderated panel to enhance opportunities for discussion and audience interaction.

Our keynote speaker is Linda A. McCauley, dean and professor of the Emory University Nell Hodgson Woodruff School of Nursing. Dean McCauley received a bachelors of science in nursing from the University of North Carolina-Chapel Hill, an MSN from Emory University and a doctorate in environmental health from the University of Cincinnati.

She is an internationally recognized leader in environmental and occupational health and conducts interdisciplinary research using participatory research models to study pesticide exposures among minority communities. Her research has been funded by the National Institutes of Health, the Centers for Disease Control and Prevention, the Department of Defense, and the Department of Veterans Affairs.

Dean McCauley is a fellow of the American Academy of Occupational Health Nurses and the Academy of Nursing, a member of the American College of Occupational and Environmental Medicine, the American Public Health Association, and is an elected member of the Institute of Medicine.

Also new this year are student poster awards: two for undergraduate and two for graduate students. The top award for each winning poster is $300, and runners up receive $150.

We hope you will join us for the St. David's CHPR conference, which will be held noon to 4 p.m., Wednesday, March 30, 2016, at the Etter-Harbin Alumni Center at 2110 San Jacinto Boulevard on the campus of UT Austin.

To register, visit the St. David's CHPR Conference registration page.

-Sharon Horner, PhD, RN, FAAN, associate dean for research, and director of the UT Austin School of Nursing's St. David's CHPR

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How Physical Environments Influence Health

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People tend to forget we live in a physical environment that can influence health. Human beings spend more than 88 percent of their lives inside built environments where they live, work and play. The problem is that building materials such as furniture, fabrics, window treatments, carpeting - or no carpeting - and mechanical systems, such as heating and air conditioning (HVAC) systems, can all influence our health.

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Technology as an Influence on Health- BT

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Technology as an Influence on Health- BT

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Now technology has been a blessing on health. With technology doctors were able to detect health problems sooner and faster. Technology has also given us computers, phones, internet, etc. that people could use to acquire accurate information on health, remedies on how to treat a small sickness, or symptoms of a sickness.

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Healthcare Training Institute in New Jersey | AIMS Education

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Unlock your potential at AIMS Education! Discover diverse degree programs, expert training, and resources to advance your career in healthcare.

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Behavior is very important towards all types of health, there are many causes that influence behavior. Drugs are a very important factor that determine an individuals health. For instance, Tobacco leads to cancer, and heart disease, and smoking tobacco leads to second hand smoke which harms others. A person's behavior is also determined by their diet, and activities. The less exercise you do the more prone you are to deadly diseases.

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TOBACCO USE

Since the release in 1964 of the surgeon general's first report on smoking, there has been a tremendous increase in scientific knowledge about the health consequences of tobacco use ( U.S. Department of Health and Human Services [USDHHS], 1989; U.S. Department of Health and Human Services [USDHHS], 1990; U.S. Department of Health and Human Services [USDHHS], 2000). Cigarette-smoking is the major cause of preventable mortality and morbidity in the United States ( National Center for Health Statistics [NCHS], 1998a; USDHHS, 2000). Not only does smoking lead to an increased risk of the two leading causes of death in the United States-heart disease and cancer ( NCHS, 1998b; USDHHS, 2000)-but smoking during pregnancy has been linked to adverse pregnancy outcomes ( DiFranza and Lew, 1995; Hebel et al., 1988; LeClere and Wilson, 1997; Li et al., 1993; Shu et al., 1995; USDHHS, 2000; Ventura et al., 1997; Walsh, 1994). Nonsmoking people are not immune to tobacco's health hazards, inasmuch as exposure to second-hand smoke has serious health consequences for adults and children ( USDHHS, 1986, 2000; U.S. Environmental Protection Agency [USEPA], 1992).

Although cigarette-smoking among adults leveled off in the 1990s, tobacco use among adolescents increased in that period ( USDHHS, 2000). That cigarette-smoking among younger people has increased is particularly alarming for several reasons. Evidence shows not only that tobacco is addictive ( USDHHS, 2000) and that only a relatively small percentage of smokers can stop smoking permanently each year ( Centers for Disease Control and Prevention [CDC], 1993; Centers for Disease Control and Prevention [CDC], 1996b; USDHHS, 2000), but also that nicotine addiction develops in most smokers during adolescence ( Institute of Medicine [IOM], 1994; USDHHS, 1988a, 1994, 2000). Curbing or eradicating tobacco use might remain a daunting task. Prevention is the primary objective, but many benefits are associated with smoking cessation, and such efforts should not be ignored.

Measuring the Public Health Burden of Cigarette-Smoking

There is widespread agreement in the public health and medical communities that cigarette-smoking is the biggest external (nongenetic) contributor to death in the United States. Tobacco-related diseases account for more than 400,000 deaths among adults in the United States each year ( CDC, 1993; NCHS, 1998b; USDHHS, 2000). Deaths attributable to tobacco use have been found to exceed deaths from acquired immunodeficiency syndrome (AIDS), traffic accidents, alcohol use, suicide, homicide, fire, and use of illegal drugs combined ( IOM, 1994). One World Health Organization report showed that the burden of disease and death attributable to tobacco in developed countries was substantially higher than that attributable to any other risk factor, including alcohol use, unsafe sex, hypertension, and physical inactivity ( Murray and Lopez, 1996).

Because there is a long delay between the onset of persistent smoking and the full development of its adverse health consequences, current tobacco-attributable mortality and morbidity are consequences of smoking that began decades ago. If current U.S. tobacco use patterns persist, it is estimated that 5 million persons who were under the age of 18 in 1995 will die from a smoking-related disease ( CDC, 1996a; USDHHS, 2000).

Major Smoking-Related Diseases

According to the Surgeon General's 1990 report ( USDHHS, 1990), smoking is the most important modifiable cause of poor pregnancy outcome in the United States, It is estimated that 15-30% of all pregnant women smoke ( Chandra, 1995; Ventura et al., 1997). Pregnancy complications associated with maternal smoking include premature detachment of the placenta, development of the placenta in the lower uterine segment, which can cause hemorrhaging in the last trimester; bleeding during pregnancy; premature membrane rupture; and premature delivery. Maternal smoking also has been associated with spontaneous abortions and low birthweight ( DiFranza and Lew, 1995; Hebel et al., 1988; LeClere and Wilson, 1997; Li et al., 1993; Shu et al., 1995; USDHHS, 2000; Ventura et al., 1997; Walsh, 1994). Evidence indicates that in some groups of pregnant women smoking one to six cigarettes a day increases by about two-thirds the risk of giving birth to a low birthweight infant ( LeClere and Wilson, 1997; Ventura et al., 1997). Smoking in the last few weeks of pregnancy has the biggest impact on fetal weight gain. Women who stop smoking before becoming pregnant or who quit in the first 3-4 months of pregnancy have infants of the same birthweight as those born to women who never smoked. Women who stop smoking later in pregnancy have higher birthweight infants than do women who smoke throughout pregnancy.

The complex issues associated with the real and perceived risk of tobacco and tobacco harm-reduction products are explored in an IOM report (2001).

Consequences of Second-Hand Smoke

Exposure to second-hand smoke has serious health consequences ( USDHHS, 1986, 2000; USEPA, 1992). At least 43 of the roughly 4000 chemicals identified in tobacco smoke have been shown to cause cancer in humans and animals ( USDHHS, 2000; USEPA, 1992). About 3000 nonsmoking Americans die of lung cancer and 150,000-300,000 children suffer from lower respiratory tract infections each year because of exposure to second-hand smoke ( USDHHS, 2000; USEPA, 1992). Second-hand smoke exposure exacerbates asthma and leads to 500,000 child visits to physicians each year ( DiFranza and Lew, 1996; USDHHS, 2000). Second-hand smoke exposure also has been linked to increased risk of heart disease among adults ( Glantz and Parmely, 1995; Howard et al., 1998; USDHHS, 2000). Data gathered in a study of the U.S. population over the age of 3 showed that almost 88% of nonusers of tobacco had detectable serum cotinine, a biological marker of exposure to second-hand smoke ( Pirkle et al., 1996; USDHHS, 2000). Another study showed that almost 22% of Americans under the age of 18 (about 15 million people) were exposed to second-hand smoke in their homes ( CDC, 1997b; USDHHS, 2000). A 1996 study showed that home and workplace environments contribute significantly to the widespread exposure to second-hand smoke in the United States ( Pirkle et al., 1996; USDHHS, 2000).

Socioeconomic Characteristics of Smokers

Among adolescents, tobacco use increased in the 1990s, after decreasing in the 1970s and 1980s ( USDHHS, 2000). Several factors place young people at an increased risk of initiating tobacco use ( USDHHS, 2000). Sociodemographic risk factors include low socioeconomic status of one's family. Environmental risk factors include accessibility and availability of tobacco products, cigarette advertising and promotion, the price of tobacco products, perceptions that tobacco use is normative, use and approval of tobacco use by peers and siblings, and lack of parental involvement. Personal risk factors include poor self-image and low self-esteem relative to peers, the belief that tobacco use is functional (useful or providing a benefit), and lack of confidence in one's ability to refuse an offer to use tobacco ( USDHHS, 1994, 2000).

Primary Prevention of Cigarette-Smoking

When the surgeon general's first report on smoking was released in 1964, 42% of American adults smoked tobacco; in 1995, use had declined to 24.7% (47 million) of American adults ( CDC, 1997a). Among adults, the number of former smokers (43 million) is now almost the same as current smokers (46 million) ( IOM, 1994). Given the progress since 1964, it is possible to envision a smoke-free society; however, maintaining the current rate of progress will be challenging. There is overwhelming evidence that the nicotine in tobacco is addictive ( USDHHS, 1988a, 2000). Almost 70% of current smokers want to quit smoking, and about 45% quit smoking for at least a day ( Howard et al., 1998). However, only 2.5% of smokers stop smoking permanently each year ( CDC, 1996b, 1993; USDHHS, 2000).

Nearly all first-time use of tobacco occurs before high school graduation. That is important because nicotine addiction occurs in most smokers during adolescence ( IOM, 1994; USDHHS, 1988a, 1994, 2000). Smoking patterns among American youth and the short- and long-term health consequences of initiating smoking in adolescence were described in the Surgeon General's 1994 report Preventing Tobacco Use Among Young People ( USDHHS, 1994). The same report provides a summary of efforts to prevent tobacco use among young people; such prevention emerged as a major focus of tobacco control efforts ( IOM, 1994; USDHHS, 2000).

Benefits of Smoking Cessation

Given the addictive nature of nicotine and the cumulative nature of health damage due to smoking, strategies to reduce tobacco use should emphasize primary prevention rather than smoking cessation. However, smoking's prevalence in the U.S. population points to the need to continue cessation efforts.

OBESITY: PHYSICAL ACTIVITY AND DIET

Recent years have seen an epidemic in obesity in the United States ( Mokdad et al., 1999). Obesity is a major health risk for diabetes ( Must et al., 1999), and the relationship of weight to the disease has been extensively reviewed in the literature ( Kopelman, 2000; Leong and Wilding 1999; National Task Force on the Prevention and Treatment of Obesity, 2000; Scheen, 2000; USDHHS, 1980). Overweight adults also are at an increased risk for hypertension, coronary heart disease, and some forms of cancer ( NCHS, 1998a; Pi-Sunyer, 1993). They also run the risk of developing gallbladder disease, osteoarthritis, sleep apnea, respiratory problems ( USDHHS, 2000), and a variety of musculoskeletal problems ( Foreyt et al., 1996). There is some disagreement about whether the principal threat to health is from an increase in body fat per se, or from a lack of physical activity, but there is no disagreement that major behavioral change is needed to correct this increase in obesity ( Hill and Peters, 1998; Taubes, 1998).

Although genetic factors are important, physical activity and diet contribute significantly to maintenance of appropriate body weight. The combination of inactivity and detrimental dietary patterns has been ranked as the second leading factor contributing to mortality in the United States, after tobacco use ( McGinnis and Foege, 1993). In addition, both diet and physical activity, in and of themselves, influence health. Studies show that men and women who are physically active have, on the average, lower mortality than people who are inactive ( Kaplan et al., 1987, 1996; Kujala et al., 1998; Kushi et al., 1997; Leon et al., 1987; Lindsted et al., 1991; Paffenbarger et al., 1993; Sherman et al., 1994; Slattery et al., 1989). A sedentary lifestyle has been linked to 23% of deaths from major chronic diseases ( Hahn et al., 1990). Furthermore, studies show that dietary factors are associated with 4 of the 10 leading causes of death, including coronary heart disease, stroke, some forms of cancer, and non-insulin-dependent diabetes mellitus ( CDC, 1997c; USDHHS, 2000).

This section will review some of the factors that influence obesity, with a particular emphasis on physical activity and diet, and describe the relevance of body weight, physical activity, and diet to cardiovascular disease, cancer, and musculoskeletal problems. It is not meant to be a comprehensive review but rather a sampling of the influences these behaviors can have on health and disease.

Prevalence and Trends

Obesity and overweight are increasing in the United States. Currently, "overweight" is defined as a body mass index (BMI) of 25-30 while "obesity" is defined as a BMI greater than 30 ( National Heart Lung Blood Institute Obesity Task Force, 1998). For most of the 1960s and 1970s the

prevalence of overweight adults (25-74 years of age) was nearly constant at about 25%. However, by 1988-1994, that rose to approximately 35% ( NCHS, 1998a), and the prevalence continues to increase. Obesity increased from 12% in 1991 to almost 18% in 1998 and 19% in 1999 ( Mokdad et al., 1999; 2000). Obesity in children over the age of 6 and in adolescents also is increasing ( Troiano and Flegal, 1998; USDHHS, 2000). Because overweight and obesity that develop in childhood or adolescence can persist into adulthood, this trend increases the risk for chronic disease later in life ( USDHHS, 2000).

Relatively few Americans participate in regular physical activity. Only 11% of the U.S. adult population reported regular, vigorous physical activity for 20 minutes or longer more than twice each week ( USDHHS, 2000). Furthermore, physical activity tends to decline during adolescence ( CDC, 1998; Pate et al., 1994), and a major decrease in vigorous physical activity (much more for girls than for boys) occurs in grades 9-12 ( USDHHS, 2000). A consensus is emerging that physical activity does not need to be vigorous to be beneficial to health. For people who are inactive, even small increases have been associated with measurable health benefits ( USDHHS, 2000).

In 1994-1996, the proportion of Americans who ate away from home was approximately 57%, or an increase of about one-third from the late 1970s ( USDA, 1997; USDHHS, 2000). Recent data indicate that 40% of the family food budget is spent at restaurants and carry-outs ( USDA, 1996; USDHHS, 2000). Food purchased from restaurants, fast-food outlets, school cafeterias, and vending machines generally is higher in saturated fat, cholesterol, and sodium and lower in fiber and calcium than is food prepared and eaten at home ( Lin and Frazao, 1997; USDHHS, 2000). And people tend to eat larger portions of higher calorie foods when they eat out. The larger food portions in restaurants further exacerbate this problem ( McCrory et al., 2000). One study pointed to an association between the frequency of eating restaurant food and elevated BMI ( McCrory et al., 1999). A 1995 survey found that school meals and snacks had the highest saturated-fat density of all foods people eat away from home, including food from restaurants, fast-food outlets, and vending machines ( Lin and Frazao, 1997; USDHHS, 2000). Although schools are required to plan menus that comply with U.S. dietary guidelines, these standards do not apply to a la carte foods or to foods sold in snack bars, school stores, or vending machines ( USDHHS, 2000). Because many dietary habits are established during childhood ( CDC, 1996c; Kelder et al., 1994; USDHHS, 2000), educating school-aged children about nutrition can help them establish healthy eating habits early in life. Implementation of curricula that encourage healthy eating and that provide students with the skills they need to adopt and maintain healthy eating habits has led to positive changes in student dietary behaviors and to reductions in cardiovascular disease risk factors ( CDC, 1996c; Contento et al., 1995; Lytle and Achterberg, 1995; USDHHS, 2000).

Similar increases in the incidence of overweight and obesity are evident throughout the world, although rates differ ( Flegal, 1999). In Europe obesity is especially prevalent in Southern and Eastern countries, particularly among women ( Seidell, 1995). In Sweden, between 1980 and 1996 the prevalence of obesity rose from 9% to 12% in women and from 6.6% to 10% in men ( Lissner et al., 2000). Between 1982 and 1994, the percentage of overweight people in New Zealand increased from about 53% to 64% for men and 36.5% to 45% for women ( Simmons et al., 1996). In many countries, as in the United States, obesity is an increasing concern in children (for example, Great Britain: Chinn and Rona, 2001; Germany: Kromeyer-Hauschild et al., 1999; Singapore: Ho et al., 1983). Even in the developing world, the rates of obesity are showing increases ( Shetty, 1997). As reviewed above for the United States, these international trends are attributed to high fat, energy dense diets and reduced physical activity ( Shetty, 1997; Seidell, 1995).

Socioeconomic Characteristics

Adult Weight Gain

Adult weight gain is observed in many industrialized societies. Because full adult height generally is attained by age 18, weight gain in adulthood is almost exclusively through the addition of adipose tissue. Lack of weight gain, particularly among men over 50, does not imply an absence of gain in fat. Above this age, muscle mass is, to varying degrees, redistributed to fat, much of it within the abdomen ( Rimm et al., 1995).

Avoiding weight gain as an adult is a high priority because treatment of obesity has poor long-term success, and lost weight often is regained ( Chapter 5). Several studies show that greater leisure-time physical activity is associated with lower weight gain ( Ravussin et al., 1988; Rissanen et al., 1991), and it reduces the weight gain often observed after cessation of cigarette-smoking ( Kawachi et al., 1996). Although many people try to lose weight, most regain the weight within 5 years ( NIH, 1993; USDHHS, 2000). In order to maintain weight loss, permanent lifestyle changes that combine good dietary habits, decreased sedentary behavior, and increased physical activity are essential. Changes in the physical and social environment can help people maintain the necessary long-term lifestyle changes both for diet and for physical activity ( USDHHS, 2000). Preventing weight gain in the first place also substantially reduces the likelihood that conditions such as hypertension and diabetes will develop ( Colditz et al., 1995). A reduction of even 10-15% of body weight in substantially overweight people has been shown to ameliorate hyperglycemia, hyperlipidemia, and hypertension (see Mertens and Van Gaal, 2000; Oster et al., 1999; de Leiva, 1998; Goldstein, 1992).

Weight and Disease

Diet and physical activity are behaviors that have a direct influence on weight. However, they may also have direct effects on diseases. These direct and indirect actions are explored below in examples of diseases.

Cardiovascular Diseases

Several cohort studies have documented the adverse cardiovascular health effects experienced by overweight adults. In part, cardiac failure develops as a consequence of the increased demands on the heart to supply blood to the increased body fat ( Kopelman, 2000). The Nurses Cohort Study ( Willet et al., 1995) demonstrated a 2-fold increase in coronary heart disease in overweight women and a 3.6-fold increase with obesity. Similarly, the Framingham Heart Study showed increased incidence in heart disease proportionate to excess weight ( Hubert et al., 1983). Adult weight gain is an additional risk ( Hubert et al., 1983). For example, compared with men and women who maintained weight to within 2 kg of their weight at age 18-20, those who gained 5-9.9 kg experienced a 1.5-to 2-fold higher risk of coronary heart disease ( Rimm et al., 1995; Willett et al., 1995) and hypertension ( Ascherio et al., 1992; Huang, 1998).

Many studies show that physically active people have a substantially lower risk of coronary heart disease than do the inactive ( Berlin and Colditz, 1990; Kaplan et al., 1987; Kushi et al., 1997; Leon et al., 1987; Lindsted et al., 1991; Slattery et al., 1989). Prospective data from a cohort study of 72,000 female nurses (40-65 years old in 1986) indicated that walking and vigorous physical activity reduce the incidence of coronary events ( Manson et al., 1999). Brisk walking for 3 hours or more each week reduced the risk of coronary disease by 30-40%, and increasing the time or intensity of the physical activity produced even greater reductions in risk ( Manson et al., 1999). Several clinical trials suggest that moderate physical activity can produce a similar, or even larger, reduction in blood pressure than vigorous activity does ( Hagberg et al., 1989; Marceau et al., 1993; Matsusaki et al., 1992). Although vigorous physical activity rarely is associated with myocardial infarction or sudden cardiac death ( USDHHS, 1996), some risks exist. Even persons who exercise regularly have a transient increase in the risk of sudden cardiac death during and immediately after vigorous physical activity ( Kohl et al., 1992).

More than 20 prospective studies have addressed components of diet and risk of coronary heart disease ( Willett, 1998). Research in humans and laboratory animals shows that diets low in saturated fatty acids and cholesterol are associated with low risks and rates of coronary heart disease ( USDHHS, 2000). Although consumption of trans-fatty acids increases the risk of coronary heart disease ( Ascherio et al., 1994; Expert Panel on Trans Fatty Acids and Coronary Heart Disease, 1995; Hu et al., 1997; Willett et al., 1993, Willett and Ascherio, 1994), eating foods higher in polyunsaturated fat and monounsaturated fat decreases the risk of coronary heart disease. In addition, fiber intake is strongly protective against coronary heart disease ( Willett, 1998). Emerging evidence suggests that low folate and high circulating concentrations of homocysteine are major contributors to risk of coronary heart disease and stroke ( Boushey et al., 1995; Chasan-Taber et al., 1996; Rimm et al., 1996; Selhub et al., 1995). Vitamin E appears to reduce the risk of coronary heart disease ( Rimm et al., 1993; Stampfer et al., 1993).

Cancer

Obesity has been associated with an increased risk for some forms of cancer. The data have been most consistent for postmenopausal breast cancer ( Barnes-Josiah et al., 1995; Huang et al., 1997) and endometrial cancer ( Le Marchand et al., 1991). A prospective study by Sonnenschein et al, (1999) reported a relative risk for breast cancer of 2.36 in postmenopausal women in the fourth quartile of BMI. Women in this weight range also showed a 4-fold greater risk for endometrial cancer ( Goodman et al., 1997). The mechanisms of these effects are not known, but they could be related to levels of sex hormones.

Physical inactivity has been examined as a contributing factor in a variety of cancers. Many studies conducted in men show an inverse relationship between physical activity and risk of colon cancer ( Giovannucci et al., 1995; Lee et al., 1991; Severson et al., 1989; Slattery et al., 1988; Whittemore et al., 1990; Wu et al., 1987). A large prospective cohort study in women found a similarly strong inverse association between physical activity and colon cancer ( Martinez et al., 1997). Physical activity not only increases intestinal motility ( Thor et al., 1985) and aids in the suppression of colon cell proliferation ( Lee, 1994; Shephard et al., 1991), but it is hypothesized to decrease gastrointestinal transit time ( Lee, 1994; Shephard, 1993) and thus the duration of contact between the colon mucosa and potential carcinogens.

Increased physical activity has been hypothesized to prevent breast cancer by reducing cumulative lifetime exposure to circulating ovarian hormones ( Kramer and Wells, 1996). However, the epidemiologic findings are inconsistent. Several studies report reductions in breast cancer risk with more physical activity ( Bernstein et al., 1994; D'Avanzo et al., 1996; Mittendorf et al., 1995; Thune et al., 1997); others found a modest association at best ( Albanes et al., 1989; Chen et al., 1997; Friedenreich and Rohan, 1995; Gammon et al., 1998; McTiernan et al., 1996; Rockhill et al., 1998) or even increased risk ( Albanes et al., 1989; Dorgan et al., 1994). Similarly, findings from studies on the relationship between physical activity and prostate cancer are inconsistent ( USDHHS, 1996).

Diet also could be an etiologic factor in cancer. For instance, evidence indicates that low folate intake works a role in the development of colon cancer ( Freudenheim et al., 1991; Giovannucci et al., 1998; Mason and Levesque, 1996). A consistent relationship between intake of fruit and vegetables and lower risk of many malignancies supports an anticancer effect of some component of these foods ( Steinmetz and Potter, 1991). Yet, despite epidemiologic evidence that fruits and vegetables that contain carotenoids reduce the risk of lung cancer ( Ziegler et al., 1996), randomized trials of the specific carotenoid, ß-carotene, fail to show any benefit ( Albanes et al., 1996; Hennekens et al., 1996). In fact, the ß-Carotene and Retinol Efficacy Trial ( Omenn et al., 1996) found an increase in mortality in patients taking supplements of ß-carotene and vitamin A. Evidence linking high-fatty-acid diets with cancer are inconclusive, and there is continuing debate about the relationship between colorectal, prostate, and breast cancers and total fat content or type of fat in the diet ( NRC 1989; Ip and Carroll, 1997; USDHHS, 2000). Randomized clinical trials are attempting to clarify the relationship between dietary total fat and the risk of cancer ( Freeman et al., 1993; Schatzkin et al., 1996; USDHHS, 2000).

Musculoskeletal Health

Physical activity contributes to the development of bone mass during childhood and adolescence and to the maintenance of skeletal mass during adulthood ( USDHHS, 1996). Increased bone mineral density is positively associated with aerobic exercise ( Snow-Harter et al., 1996; USDHHS, 2000). Through its load-bearing effect on the skeleton, physical activity influences bone density and bone architecture-the higher the load, the greater the bone mass ( Lanyon, 1987, 1993). Conversely, if the skeleton is unloaded, because of inactivity or immobility, bone mass declines.

Calcium intake is essential for the formation and maintenance of bones ( USDHHS, 1988b; USDHHS, 2000). Higher calcium intake has been linked to increased bone density in short-term studies, but high protein intake and high dairy calcium intake are both related to increased risk of fractures in long-term prospective studies of men and women ( Feskanich et al., 1996, 1997; Owusu et al., 1997, 1998). Because ideal calcium intake for development of peak bone mass has not been determined, it has not been established to what extent increased calcium intake will prevent osteoporosis.

Although most young children meet the dietary requirements for calcium, the intake of calcium declines precipitously with age ( USDHHS, 2000). In part as a consequence of inadequate calcium in the diet, osteoporosis is prevalent, affecting more than 25 million people in the United States alone. It is the principal underlying cause of bone fractures in postmenopausal women and the elderly ( NIH, 1994; USDHHS, 2000). Physical activity can help. Strength training has been shown to help post-menopausal women preserve bone density ( Nelson et al., 1994; USDHHS, 2000).

In addition to strengthening bone, physical activity reduces the risk of fractures in the elderly by increasing muscle strength and balance, thus reducing the risk of falling. Muscle strength has been shown to decline with age, and studies have documented a relationship between muscle strength and physical function ( Brown et al., 1995; USDHHS, 2000). However, age-related loss of strength can be attenuated with strengthening exercises and this can help the older population maintain a threshold of strength necessary to perform basic weight-bearing activities, such as walking ( Evans, 1995; Tseng et al., 1995; USDHHS, 2000). Thus, regular physical activity can help to maintain the functional independence of the elderly population ( Buchner, 1997; LaCroix et al., 1993; Nelson et al., 1994).

Osteoarthritis, the most common form of arthritis, increases with age, and it is the leading cause of activity limitation among older persons ( USDHHS, 1996). Although some competitive athletic activities (such as running, soccer, football, and weight-lifting) are associated with increased risk of osteoarthritis in specific joints ( USDHHS, 1996), regular noncompetitive physical activity is not harmful to joints ( Lane, 1995; Panush and Lane, 1994) and might actually relieve symptoms and improve functioning among persons who already have osteoarthritis or rheumatoid arthritis ( Ettinger et al., 1997; Ettinger and Afable, 1994; Fisher and Pendergast, 1994; Minor, 1991).

Physical activity poses some potential risks. Musculoskeletal injury is the most common. Increased risks of roadway accidents also could be associated with running or bicycling on roads, and various sports are associated with specific hazards, such as downhill skiing at high velocities and collisions with other players in football and hockey.

ALCOHOL CONSUMPTION

Alcohol has been identified as a top contributor to death in the United States ( McGinnis and Foege, 1993), after tobacco use and diet and activity patterns. Compared with other threats to human health, alcohol causes the widest variety of injuries ( Rose, 1992). Approximately 100,000 deaths are related to alcohol consumption in the United States each year ( McGinnis and Foege, 1993; Rose, 1992), which translates into 15% of potential years of life lost before the age of 65 ( Rose, 1992).

A significant proportion of the U.S. population drinks alcohol. Among current drinkers, 46% report having been intoxicated at least once in the past year, and almost 4% report having been intoxicated weekly ( USDHHS, 2000). Almost 10% of current drinkers (approximately 8 million people) meet diagnostic criteria for alcohol dependence, and an additional 7% (more than 5.6 million people) meet diagnostic criteria for alcohol abuse ( National Institute on Alcohol Abuse and Alcoholism [NIAAA], 1993; USDHHS, 2000). In 1995, the cost of alcohol abuse and alcoholism was estimated at $167 billion in the United States, of which more than two-thirds was due to lost productivity ( Harwood et al., 1998; USDHHS, 2000).

Alcohol use and alcohol-related problems are common among adolescents ( O'Malley et al., 1998; USDHHS, 2000). Research shows that the age at which a person starts drinking strongly predicts development of alcohol dependence over a lifetime. Approximately 40% of people who begin drinking before the age of 15 develop alcohol dependence at some stage in their lives. About 10% of people who begin drinking at age 21 or older develop alcohol dependence at some stage in life ( Grant and Dawson, 1997; USDHHS, 2000). People with a family history of alcoholism have a higher prevalence of lifetime alcohol dependence than do those with no such history ( Grant, 1998; USDHHS, 2000).

Socioeconomic Factors

Studies conducted in 1994-1996 showed that people of both sexes and all races and ethnic groups-with the exception of Hispanic women- displayed a strong inverse relationship between education and heavy alcohol consumption ( NCHS, 1998a). Generally, heavy drinking tends to decrease with education, and moderate alcohol use increases with education ( NCHS, 1998a; Substance Abuse and Mental Health Services Administration, 1993). In 1994-1996, African American men and women with less than a high school education were almost twice as likely to report heavy alcohol use as were those who had more than a high school education ( NCHS, 1998a). White men with high school diplomas were 20% more likely to report heavy alcohol use than were those with more education. White women with less than a high school diploma were 40% more likely to report heavy drinking than were women with more education.

Negative Health Effects

As early as 1926, a U-shaped relationship was described between mortality and consumption of alcohol ( Pearl, 1926). The wide range of alcohol-induced illnesses and injuries is primarily attributable to differences in the amount, duration, and patterns of alcohol consumption as well as to differences in genetic vulnerability to particular alcohol-related consequences ( USDHHS, 1997a; 2000). Long-term excessive drinking increases risk for high blood pressure, irregularities of heart rhythm (i.e., arrhythmias), disorders of the heart muscle (i.e., cardiomyopathy), and stroke ( USDHHS, 2000). Long-term, heavy drinking also increases the risk of developing cancer of the esophagus, mouth, throat, and voice box and of the colon and rectum ( NIAAA, 1993; USDHHS, 2000). Alcohol consumption appears to increase the risk of breast cancer in women ( Smith-Warner et al., 1998); consumption of two or more drinks per day has been shown to slightly increase women's risk of developing breast cancer ( Reichman, 1994; USDHHS, 2000). The Dietary Guidelines for Americans ( USDA, 1995a) advises women to consume no more than 1 drink per day; while men are advised to consume no more than two per day. Because men and women have less body water as they age, older persons can lower their risk of alcohol problems by drinking no more than one drink per day ( Dufour et al., 1992; USDHHS, 2000). Heavy and chronic alcohol use is a cause of poor pregnancy outcomes ( NCHS, 1998a; USDHHS, 1993), including fetal alcohol syndrome, a major nongenetic cause of mental retardation ( American Academy of Pediatrics, 1993; Bagheri et al., 1998; IOM, 1996). Sustained heavy alcohol consumption worsens the outcome for patients with hepatitis C ( NIH, 1997a; USDHHS, 2000) and increases the risk for cirrhosis and other liver disorders ( Saadatamand et al., 1997; USDHHS, 2000). Cirrhosis, primarily attributable to heavy drinking, is one of the 10 leading causes of death in the United States ( Bureau of the Census, 1997; Hasin et al., 1990; Popham et al., 1984; Saadatamand et al., 1997; Schmidt, 1980).

Progress has been made in reducing the rate of alcohol-related driving fatalities, but it is still a serious problem. Overall, the rate of alcohol-related driving fatalities declined from 9.8 deaths per 100,000 people in 1987 to 6.5 per 100,000 in 1996 ( USDHHS, 2000). It is estimated that even at current rates, 3 out of every 10 Americans will be involved in an alcohol-related crash sometime during their lives. The populations of greatest concern for alcohol-related driving fatalities include Native Americans and those between the ages of 15 and 24. In 1994, the alcohol involvement rate in fatal traffic crashes for American Indian and Alaska Native males was 4 times higher (28 per 100,000 population) than for the general population, and, for 15- to 24-year olds, the rate was almost 13 per 100,000 population ( USDHHS, 2000).

The consequences of excessive alcohol consumption extend beyond death rates. Alcohol consumption also contributes to risk of injury. In addition to injuries and deaths from traffic accidents, a significant proportion of injuries and deaths from falls, fires, and drowning has been linked with use of alcohol ( Saadatamand et al., 1997; USDHHS, 2000). Alcohol consumption contributes to destruction of personal and social relationships ( Brookoff et al., 1997); it is a factor in homicide, suicide, marital violence, and child abuse ( Roizen, 1993; USDHHS, 2000); and it contributes to high-risk sexual behavior ( Strunin and Hingson, 1992, 1993; USDHHS, 2000).

Positive Health Effects

In contrast with those harmful effects, however, evidence is overwhelming of a beneficial effect of moderate consumption of alcohol (1-2 drinks per day) on reducing risk of coronary heart disease and thrombotic stroke. Light-to-moderate drinking can have beneficial effects on the heart, especially among people at greatest risk for heart attacks, including men over age 45 and women after menopause ( USDHHS, 2000; Zakhari, 1997). Moderate alcohol-drinking reduces the risk of death from those cardiovascular causes, on the average, by approximately 20-40% ( Doll, 1997; Thun et al., 1997). A reduction in cardiovascular disease mortality will translate into a reduction in total mortality in many populations because cardiovascular disease is by far the leading cause of death in middle and old age. The inverse association between alcohol consumption and cardiovascular disease risk is causal: ethanol has been shown in short-term experimental studies to increase the serum concentration of high-density lipoprotein cholesterol ( Rimm et al., 1999), and it also appears to affect platelet function and other components of clotting and fibrinolysis ( Hendriks et al., 1994; Meade et al., 1987; Renaud et al., 1992).

Quantifying Net Public Health Benefit

The positive and negative effects of alcohol on mortality raise the question, "Is alcohol consumption good for health?" The answer is conditional. The net benefit of alcohol consumption in a population depends on age distribution of the population, because the ratio of mortality from conditions that are prevented by alcohol to mortality from conditions that are made more common by it varies greatly with age. The net benefit also will vary with the population prevalence of factors that predispose to (or protect from) cardiovascular disease, and they might differ in men and women.

Although alcohol consumption is unlikely to reduce total mortality in people under 45 ( Doll, 1997), the optimal duration of moderate alcohol consumption is not known in terms of reducing risk of cardiovascular disease mortality in older people. Furthermore, even though some of the benefits of alcohol are the result of long-term, habitual consumption ( Jackson et al., 1992), many of the important effects of ethanol on high-density lipoproteins and clotting components are acute; thus, it is likely that alcohol consumption beginning in middle age would suffice while avoiding much of the risk of injuries and other external causes of death (although not necessarily of cancers or cirrhosis of the liver).

Optimal alcohol consumption differs for men and women for several reasons. Women metabolize alcohol less efficiently than men do (making women more prone to some health problems than are men who drink the same amount), and because women have less body water than men (making them more prone to intoxication than men after drinking the same amount of alcohol) ( USDHHS, 2000). Women also have lower age-specific risks of cardiovascular disease and greater susceptibility to liver damage than men, and women are prone to a relatively high risk of breast cancer, which appears to increase with consumption of any amount of alcohol ( Smith-Warner et al., 1998). Although men might be at risk for alcohol-related problems if they consume more than 14 drinks per week or more than 4 drinks per occasion, women could be at risk if they consume more than 7 drinks per week or more than 3 per occasion ( USDHHS, 1995, 2000).

The problem of alcohol consumption is frequently one of maldistribution, with many abstaining and many consuming at a hazardous level ( Holman and English, 1996). There seems to be no precedent for a public health campaign that simultaneously seeks to "pull in" both tails of a risk factor distribution, in this case reduction of both the prevalence of abstention and of heavy drinking ( Holman and English, 1996). There are risks in promoting a population wide alcohol policy that discourages abstention, even if the policy encourages only light-to-moderate regular consumption. First, there is no evidence that moderate drinking is harmless. Second, a public health recommendation that encourages even light drinking over abstention could increase the number of heavy drinkers in a population since it has been noted that population distributions of risk factors tend to shift, either downward or upward, as an entity ( Rose, 1992). Researchers have noted that it is unethical for governments and other public institutions to promote low alcohol intake as a disease prevention measure because of the potential adverse risks at the population level, but they also note that it is similarly unethical to promote abstinence ( Holman and English, 1996). In an editorial accompanying publication of a large study by the American Cancer Society, a question was raised about whether alcohol consumption is the method of choice for preventing cardiovascular disease. One important consideration is whether physical activity and diet would be as effective as moderate alcohol consumption-with lower risk of harm-in lowering cardiovascular disease mortality ( Potter, 1997). The data on physical activity and some dietary factors would seem to suggest that they are equally effective, and they have the additional benefit of reducing risks of many other diseases.

SEXUAL PRACTICES

Sexual relationships and practices are complex to investigate, but their study is important because infectious disease has always been a possible outcome of sexual relationships, as has unwanted pregnancy. Both are crucial public health issues of our time. Recently released figures show that the United States is among the highest in incidence and prevalence of sexually transmitted infection (also called sexually transmitted disease) in the industrialized world ( USDHHS, 2000).

Concern about AIDS has been an important motivation for recent studies of sexual behaviors, including a large national survey of sexual behaviors and attitudes ( Laumann, 1994). Most of the issues that arise in relating sexual behavior to risk of infection with the human immunodeficiency virus (HIV) pertain to many other, far more common, sexually transmitted infections. But HIV has made unsafe sex a matter of life and death. In 1995, there were more than 43,000 deaths from AIDS in the United States, making it the eighth-leading cause of death in that year, and the leading cause of death among Americans 25-44 years old ( Anderson et al., 1997). It is now the second-leading cause of death among all Americans aged 25-44, but it is the leading cause of death for African Americans in this age group ( USDHHS, 2000). Other, more common sexually transmitted infections-human papilloma virus, gonorrhea, chlamydia, and genital herpes-vary in the severity of their consequences; but if left untreated, these diseases can compromise health and even become life threatening.

Prevalence of Sexually Transmitted Infections

In 1996, the United States had 15.3 million new cases of sexually transmitted infection. This was higher than the 12 million annual new cases estimated by the Centers for Disease Control and Prevention a decade before ( Tanne, 1998). The increase is partly real and partly the result of more sensitive tests that can now identify asymptomatic infection.

More than 68 million Americans now have an incurable sexually transmitted infection ( Tanne, 1998); for instance, 1 out of every 5 Americans has genital herpes ( Tanne, 1998). Every year, 15 million people are infected with a sexually transmitted disease, almost 4 million of them teenagers ( American Social Health Association, 1998; USDHHS, 2000). Sexually transmitted infections are more prevalent in teenagers and young adults than in older persons, partly because of the greater propensity of younger persons to engage in unprotected sex and to switch sexual partners relatively frequently ( Laumann, 1994). Despite its prominence in the media, AIDS represents only a tiny proportion of sexually transmitted infections, basically less than half of one percent of all the new cases of sexually transmitted infection ( Laumann, 1994). The most commonly reported sexually transmitted infection in the United States is chlamydia, with 3 million new cases each year ( Tanne, 1998). The direct and indirect costs of the primary sexually transmitted diseases and their complications, including sexually transmitted HIV infection, are estimated at $17 billion each year ( St. Louis et al., 1997; USDHHS, 2000).

Data from a University of Chicago national survey on sexual behaviors ( Laumann, 1994) indicate that 16.9% of U.S. adults aged 18-59 years old have had a sexually transmitted infection (15.9% of men, 17.8% of women). The risk of sexually transmitted infection rises monotonically and dramatically with the number of sex partners. Lifetime occurrence of any sexually transmitted infection rises from 4% for those with only one partner after the age of 18 years to 40.4% for those with more than 20 partners. The number of sex partners is the most succinct measure of the extent of exposure to infection. Another important aspect of extent of exposure is type of sexual practice: anal intercourse is an especially efficient way of transmitting infections, especially HIV, because it often leads to small breaks in the skin.

Contributing Factors That Affect Transmission

Although sexually transmitted infections are behavior-linked diseases that result from unprotected sex ( IOM, 1997; USDHHS, 2000), other factors contribute to their rapid spread in a population. Because most sexually transmitted infections are asymptomatic, or produce very mild symptoms, they often are disregarded, so infected persons do not seek immediate medical care. About 85% of women and about 50% of men with chlamydia have no symptoms ( Fish et al., 1989; Handsfield et al., 1986; Stamm and Holmes, 1990; USDHHS, 2000). There is also a long interval between the acquisition of a sexually transmitted infection and the eventual recognition of a clinically significant health problem; it is sometimes several years before an infection manifests itself. Thus, because the original infection is often asymptomatic, there is frequently no perceived connection between the original sexually acquired infection and the health problem associated with it.

There is an association between sexually transmitted infections and substance abuse, particularly the abuse of alcohol and other drugs. The introduction of new, illicit substances into communities, for instance, often drastically alters sexual behavior in high-risk sexual networks, thereby causing an epidemic of sexually transmitted diseases ( Marx et al., 1991; USDHHS, 2000). The epidemic in crack cocaine use intensified the U.S. syphilis epidemic in the late 1980s ( Gunn et al., 1995; USDHHS, 2000).

Sexually Transmitted Infections and Cancer

Several sexually transmitted viral infections are known or strongly suspected to cause cancer. The most important of these are the sexually transmitted types of human papilloma virus. At least 90% of the approximately 16,000 cases of cervical cancer diagnosed each year are estimated to be attributable to infection with the human papilloma virus ( Morrison et al., 1997).

A strong link between hepatitis B and hepatitis C viruses and hepatocellular carcinoma (liver cancer) became evident during the 1980s. Hepatitis B infection occurs more frequently among persons who have multiple sex partners and who also have a history of sexually transmitted infection. An estimated 53,000 cases of hepatitis B virus (out of a total of 200,000- 300,000 cases) were sexually transmitted in the United States in 1994 ( IOM, 1997).

Disproportionate Affliction of Sexually Transmitted Infections

Although people in all communities-including all racial, cultural, economic, and religious groups-and sexual networks are at risk for sexually transmitted infections, some are disproportionately affected by these diseases and their associated complications. For instance, not only do sexually transmitted diseases occur more frequently in women than in men, but women also suffer more serious complications ( USDHHS, 2000), including pelvic inflammatory disease, ectopic pregnancy, infertility, and chronic pelvic pain ( Chandra and Stephen, 1998; USDHHS, 2000). In addition, women are biologically more susceptible to infection when exposed to a sexually transmitted disease agent, and sexually transmitted diseases are more difficult to diagnose in women because of female physiology and the anatomy of the reproductive tract ( USDHHS, 2000).

Rates of sexually transmitted diseases are higher for minority and ethnic groups (primarily African American and Hispanic populations) than for whites. For example, although chlamydia is a widely distributed sexually transmitted infection in all racial and ethnic groups, the prevalence is higher in minorities. In 1996, African Americans accounted for approximately 78% of the total number of gonorrhea cases reported-32 times the rate for whites. These high rates also apply to African American adolescents and young adults, with the average about 24 times higher than that for 15- to 19-year-old white adolescents and 30 times higher than for 20- to 24 year-old whites in 1996. In 1996, the gonorrhea rate for Hispanics was 3 times the rate for whites. Since 1990, syphilis rates have declined in all racial and ethnic groups, except for American Indians and Alaska Natives, but the rates for African Americans and Hispanics continue to be greater than those for non-Hispanic whites. In 1996. African Americans accounted for approximately 84% of all reported cases of syphilis ( USDHHS, 2000).

Young, heterosexual women, especially minorities, are increasingly acquiring HIV infection and developing AIDS. In 1996, 39% of the reported AIDS cases occurred in 13- to 24-year-olds and, of the AIDS cases reported in women, almost 4 of every 5 occurred in the minority population, consisting primarily of African Americans or Hispanics ( USDHHS, 2000).

Prevention of Sexually Transmitted Infections

Behavioral means for prevention of sexually transmitted infections include delaying the onset of sexual activity, limiting the number of partners, abstaining from sex with people not known to be infection free, and using effective barrier contraception.

DISEASE SCREENING PRACTICES

Screening asymptomatic persons to detect preclinical disease has become an important part of public health. But preclinical screening makes sense only if treatment initiated earlier in the disease process will reduce morbidity and mortality from the disease: there is no benefit in living with a diagnosis if a person's life or quality of life is not extended. Although some screening tests can be highly effective in reducing morbidity and mortality, others are of unproven benefit. Poor specificity can produce a large number of false-positives, which in turn can lead to unnecessary and potentially harmful follow-up with diagnostic testing and treatment and needless psychological distress.

The selection of appropriate tests for a given individual depends primarily on that person's age and sex. In addition, consideration of individual risk factors, such as lifestyle or family history, often is used to determine which tests are appropriate tests and how often testing should be done.

In 1984, the U.S. Public Health Service commissioned the U.S. Preventive Services Task Force. This panel was charged with developing recommendations for clinicians on the appropriate use of preventive interventions, including screening for preclinical disease and screening for disease risk, based on a systematic review of evidence of clinical effectiveness. In 1989, the first Guide to Clinical Preventive Services ( U.S. Preventive Services Task Force, 1989) was published. In 1990, the task force was reconvened to continue and update the scientific review process through examination of new and emerging evidence on preventive interventions. The second edition of the Guide to Clinical Preventive Services ( U.S. Preventive Services Task Force, 1996) was published in 1996. Much of the discussion below concerning screening tests for the major chronic diseases of middle and older age derives from that Guide.

According to the task force, screening must satisfy two major requirements to be considered effective for use in a population. First, the test must be able to detect the target condition earlier than would be possible without screening and with enough accuracy to preclude large numbers of false-positive and false-negative results. Second, screening for and treating persons with early disease should improve the likelihood of favorable health outcomes (e.g., reduced disease-specific morbidity or mortality) as compared with what would happen in treating patients who present on their own with signs or symptoms of the disease. In addition, the tests must be cost-effective and acceptable to the target population (fear of or distaste for colorectal screening and tests involving drawing of blood, for example, could prevent some people from participating). Documented effectiveness should be the most basic requirement for providing a health care service ( U.S. Preventive Services Task Force, 1996).

Primary versus Secondary Prevention

Primary prevention aims to reduce the incidence of disease; secondary prevention attempts to prevent the prevalence of disease, usually by shortening the course of the disease through early and effective intervention. Screening, as a component of early detection of extant disease, is one aspect of secondary prevention. However, some forms of screening, such as high-blood-cholesterol or high-blood-pressure screening, can be thought of as primary prevention for cardiovascular disease-they are in essence screening for risk of disease. As the tests have become better able to detect very early stages of such diseases as cancer (for example, in situ breast cancer and very small colon polyps), the boundary between primary and secondary prevention has blurred.

The following is a summary of general guidelines for screening for the major chronic diseases of middle and older ages. For people with unusual family histories of disease, or other medical concerns, screening procedures can vary at the discretion of the physician.

Screening for Hypertension and High Blood Cholesterol

The U.S. Preventive Services Task Force recommends screening for hypertension for all children and adults ( U.S. Preventive Services Task Force, 1996). The prevalence of hypertension increases with age, and it is more common in African Americans than whites. It is estimated that 40- 50 million Americans have hypertension ( Burt et al., 1995). Office sphygmomanometry (use of the blood pressure cuff) is the most appropriate way to screen for hypertension in the general population. However, there are special problems with accuracy when testing children under the age of 3. (The definition of hypertension in childhood is somewhat arbitrary, based on age-specific percentiles.)

Along with hypertension, elevated blood cholesterol is a major modifiable risk factor for cardiovascular disease. Total cholesterol can be measured in venipuncture or fingerstick specimens from fasting or nonfasting individuals. Because of normal physiologic variation and measurement error, a single cholesterol measurement might not reflect a person's true average concentration. A single measurement of blood cholesterol can vary by as much as 14% from an individual's average value, under normal laboratory circumstances ( Cooper et al., 1992). For this reason, some experts advise telling people their "cholesterol range," rather than providing them with a single value ( Belsey and Baer, 1990). When a precise estimate of blood cholesterol is needed, an average of two or three measures has been recommended.

Based on evidence from clinical trials showing that lowering serum cholesterol can reduce risk of coronary heart disease, periodic screening for high blood cholesterol (once every 5 years) is recommended for all men aged 35-65 ( U.S. Preventive Services Task Force, 1996). Although there are few trial data pertaining to women, the epidemiology and pathophysiology of coronary heart disease is similar in men and women, and it is likely that reduction of high cholesterol will benefit women as well. However, the later onset of coronary heart disease in women, due to protection from estrogen, suggests that routine screening for high cholesterol in women should begin around age 45. Thus, periodic screening is recommended for women aged 45-65 ( U.S. Preventive Services Task Force, 1996).

According to the U.S. Preventive Services Task Force, there is insufficient evidence to recommend for or against routine screening of all asymptomatic persons over age 65. Cholesterol appears to plateau by age 65 in women, and earlier in men ( U.S. Preventive Services Task Force, 1996). Continued screening, therefore, would be less important in persons who have shown desirable concentrations throughout middle age. However, screening in older persons might be recommended on a case-by-case basis. Older persons with important coronary heart disease risk factors, such as smoking, hypertension, or diabetes, could be more likely to benefit from screening, based on their high risk of coronary heart disease and the proven benefits of lowering cholesterol in older persons with symptomatic coronary heart disease. There is also insufficient evidence to recommend for or against routine screening in children, adolescents, or young adults; again, however, screening could be recommended for people who have a family history of very high cholesterol, premature coronary heart disease in a first-degree relative, or major risk factors for coronary heart disease.

Cervical Cancer Screening

The Pap smear is the principal screening test for cervical cancer. The U.S. Preventive Services Task Force, American Cancer Society, the National Cancer Institute, the American College of Obstetricians and Gynecologists, and the American Medical Association recommend that all women who are or have been sexually active, or who are 18 years of age or older, should have annual Pap smears. The recommendation permits Pap testing less frequently after 3 or more normal annual smears, at the discretion of individual physicians. There is no consensus on the age at which to discontinue Pap testing.

Colorectal Cancer Screening

Colorectal cancer is the second-most-common form of cancer in the United States, after lung cancer, and is the second-leading cause of cancer death. Each year, about 140,000 new cases are diagnosed, and 55,000 persons die of the disease ( NCHS, 1998b). The average patient who dies of colorectal cancer loses 13 years of life, and in addition to the mortality associated with this disease, its treatment can produce significant morbidity. Screening for early-stage colorectal cancer as well as its precursor lesions (adenomatous polyps) thus can significantly reduce morbidity and mortality associated with colorectal cancer.

Screening for colorectal cancer is recommended by a variety of groups for all persons aged 50 years and older, although there is no consensus about whether FOBT or sigmoidoscopy, or a combination of the two, produces the greatest benefit. For persons with a family history of colorectal cancer, screening is recommended to begin at an earlier age, particularly if a family member was diagnosed with colorectal cancer at a young age. For persons with a family history of hereditary syndromes associated with very high risk of colorectal cancer, and for those with a previous diagnosis of high-risk adenomatous polyps or colon cancer, regular screening with colonoscopy (at least once a year) is part of routine management. As mentioned above, FOBT screening should be performed annually to achieve maximum benefit. There is insufficient evidence to determine the optimal screening interval for sigmoidoscopy; however, a frequency of 3-5 years has been recommended by some expert groups.

Prostate Cancer Screening

The absence of proof that screening can reduce mortality from prostate cancer, together with the strong potential that screening will increase treatment-related morbidity, argue against a policy of routine screening in asymptomatic men. Thus, the U.S. Preventive Services Task Force (1996) does not recommend routine screening for prostate cancer. However, the American Cancer Society does recommend yearly PSA testing beginning at age 50 for white men and at age 40 for African American men, in whom risk of the disease is higher.

Breast Cancer Screening

Each year, some 180,000 women are diagnosed with breast cancer in the United States ( NCHS, 1998b). This accounts for about 30% of all incident cancers among women. Each year, 44,000 women die of breast cancer ( NCHS, 1998b), making it the second-leading cause of cancer deaths among American women, after lung cancer. Breast cancer is extremely rare among women younger than 20, and is uncommon among women under the age of 30. Incidence rates increase sharply with age, however, and become substantial before age 50 years. Rates continue to rise, although less quickly, in postmenopausal women.

Based on data from clinical trials, there is disagreement in the scientific community over whether routine mammographic screening should be recommended for women in their forties. This disagreement has at times been strident and strong ( Taubes, 1997). Although none of the randomized clinical trials enrolled enough women in their forties to study the benefit of screening in this age group with statistical confidence, a summary analysis of the trials nonetheless suggested a benefit. The magnitude (10-15% reduction in breast cancer mortality risk over roughly a 10-year period) was smaller than the benefit observed in women aged 50 and older ( U.S. Preventive Services Task Force, 1996). A consensus conference convened by NIH in 1997 to examine the question of whether regular mammography screening should be recommended for women in their forties. The group concluded that the decision to screen should be made by individual women in consultation with their physicians ( NIH, 1997b). The American College of Physicians, the U.S. Preventive Services Task Force, and the National Cancer Institute agree with that conclusion, but other groups (the American Cancer Society, the American College of Obstetricians and Gynecologists, and the American Medical Association) defer, recommending annual routine mammography for women aged 40-49 ( U.S. Preventive Services Task Force, 1996). A detailed review of the literature on behavior change and health communication issues associated with mammography is provided in an IOM report (2001b).

Screening for Sexually Transmitted Diseases

Screening and treatment of sexually transmitted diseases affect both transmission and duration. Studies show that screening for sexually transmitted diseases meets criteria for a successful preventive intervention ( USDHHS, 2000; U.S. Preventive Services Task Force, 1996). During the 1990s, for example, significant progress was made toward reducing the burden of disease of the common bacterial sexually transmitted diseases in the United States (i.e., gonorrhea and syphilis) ( USDHHS, 2000). For those diseases that often are asymptomatic, research indicates that screening and proper treatment even benefit people who are likely to suffer acute complications if infections are not detected and treated early ( Hillis et al., 1995; USDHHS, 2000). For instance, data are becoming available indicating that chlamydia screening is reducing disease burden and preventing associated complications ( USDHHS, 2000). In a randomized, controlled trial conducted by a managed care organization, screening for chlamydia was demonstrated to reduce the incidence of subsequent pelvic inflammatory disease by 56% in a screened group ( Scholes et al., 1996; USDHHS, 2000). Selective chlamydia screening in the Pacific North-west decreased disease burden by 60% in 5 years in the screened population ( Britton et al., 1992; USDHHS, 2000).

Testing has been identified, as has counseling, as an effective tool for assisting HIV-infected individuals both in coping with their infections and in preventing them from infecting other people. The combination of counseling and testing provides the opportunity to guide people with seronegative test results on behaviors and strategies for avoiding infection, in addition to referring them to other needed medical and social services. After the 1994 findings that perinatal HIV transmission rates could be considerably reduced with zidovudine therapy, the Public Health Service issued guidelines suggesting that HIV counseling and voluntary testing be a part of routine prenatal care for pregnant women ( USDHHS, 2000). A primary objective of this policy is to ensure that HIV-infected women have access to adequate health care for themselves and have the opportunity to reduce the risk of HIV transmission to their babies.

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32. U.S. Preventive Services Task Force. Guide to Clinical Preventive Services. Philadelphia: Williams and Wilkins; 1989.

33. U.S. Preventive Services Task Force. Guide to Clinical Preventive Services. 2nd edition. Washington, DC: U.S. Department of Health and Human Services; 1996.

34. USDA (U.S. Department of Agriculture), USDHHS (U. S. Department of Health and Human Services). Report of the Dietary Guidelines Advisory Committee on the Dietary Guidelines for Americans. Beltsville, MD: U.S. Department of Agriculture, Agricultural Research Service; 1995a.

35. USDA (U.S. Department of Agriculture), USDHHS (U. S. Department of Health and Human Services). Nutrition and Your Health: Dietary Guidelines for Americans. Washington, DC: U.S. Government Printing Office; 1995b.

36. USDA (U.S. Department of Agriculture). Dietary Guidelines for Americans. 4th edition. Washington, DC: U.S. Department of Agriculture, Agricultural Research Service; 1995a. (USDA Home and Garden Bulletin No. 232)

37. USDA (U.S. Department of Agriculture). The Healthy Eating Index (USDA Publication CNPP-1). Washington, DC: U.S. Department of Agriculture, Center for Nutrition Policy and Promotion; 1995b.

38. USDA (U.S. Department of Agriculture). What we eat in America: Results from the1994-96 Continuing Survey of Food Intakes by Individuals. (Fact Sheet). Beltsville, MD: Agricultural Research Service, Human Nutrition Research Center, Food Surveys Research Group; 1997.

39. USDHHS (U.S. Department of Health and Human Services). The Health Consequences of Smoking: Cardiovascular Disease. A Report of the Surgeon General. Rockville, MD: Centers for Disease Control, Center for Health Promotion and Education, Office on Smoking and Health; 1983.

40. USDHHS (U.S. Department of Health and Human Services). The Health Consequences of Involuntary Smoking. A Report of the Surgeon General. Rockville, MD: Centers for Disease Control, Center for Health Promotion and Education, Office on Smoking and Health; 1986.

41. USDHHS (U.S. Department of Health and Human Services). The Health Consequences of Smoking: Nicotine Addiction: A Report of the Surgeon General. Rockville, MD: Centers for Disease Control, Center for Health Promotion and Education, Office on Smoking and Health; 1988a. (DHHS publication no. (CDC) 88-8406)

42. USDHHS (U.S. Department of Health and Human Services). The Surgeon General's Report on Nutrition and Health. Washington, DC: Public Health Service; 1988b. (DHHS publication no. (PHS) 88-050210)

43. USDHHS (U.S. Department of Health and Human Services). Reducing the Health Consequences of Smoking: 25 Years of Progress. A Report of the Surgeon General. Atlanta, GA: Centers for Disease Control, National Center for Chronic Disease Prevention and Health Promotion, Office of Smoking and Health; 1989. (DHHS publication no. (CDC) 89-8411)

44. USDHHS (U.S. Department of Health and Human Services). The Health Benefits of Smoking Cessation. A Report of the Surgeon General. Rockville, MD: Centers for Disease Control, National Center for Chronic Disease Prevention and Health Promotion, Office on Smoking and Health; 1990. (DHHS publication no. (CDC) 90-8416)

45. USDHHS (U.S. Department of Health and Human Services). Eighth Special Report to Congress on Alcohol And Health. Bethesda, MD: National Institutes of Health, National Institute on Alcohol Abuse and Alcoholism; 1993.

46. USDHHS (U.S. Department of Health and Human Services). Physical Activity and Health: A Report of the Surgeon General. Atlanta, GA: Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion; 1996.

47. USDHHS (U.S. Department of Health and Human Services). Ninth Special Report to the U.S. Congress on Alcohol and Health from the Secretary of Human Services (NIH publication no. 97-4017). Bethesda, MD: National Institutes of Health, National Institute on Alcohol Abuse and Alcoholism; 1997a.

48. USDHHS (U.S. Department of Health and Human Services). Sexually Transmitted Disease Surveillance, 1996. Atlanta, GA: Centers for Disease Control and Prevention, Division of STD Prevention; 1997b.

49. USDHHS (U.S. Department of Health and Human Services). Healthy People 2010: Understanding and improving health. Washington, DC: U.S. Department of Health and Human Services; 2000.

50. USDHHS (U.S. Department of Health and Human Services). A Report of the Surgeon General. Atlanta, GA: Centers for Disease Control, National Center for Chronic Disease Prevention and Health Promotion, Office on Smoking and Health; 1994. Preventing Tobacco Use Among Young People.

51. USDHHS (U.S. Department of Health and Human Services). The Physicians Guide to Helping Patients with Alcohol Problems. Bethesda, MD: National Institutes of Health, National Institute on Alcohol Abuse and Alcoholism; 1995. (NIH publication no. 95-3769)

52. USEPA (U.S. Environmental Protection Agency). Respiratory Health Effects of Passive Smoking: Lung Cancer and Other Disorders. Washington, DC: U.S. Government Printing Office; 1992. (EPA publication no. EPA/600/6-90/006F)

53. Willett WC. Nutritional Epidemiology. In: Rothman KJ, Greenland S, editors. Modern Epidemiology. Philadelphia: Lippincott-Raven Publishers; 1998. pp. 623-642.

1

BMI is used in all these guidelines as a measure of adiposity. It is calculated as weight (in kilograms) divided by height (in meters) squared. Growing evidence suggests that BMI reflects adiposity well through middle age, but might be less clearly related to adiposity at older ages when lean muscle mass can decrease and mass is redistributed to the abdomen.

2

The correlation between BMI and body fat is both age and sex dependent, and it is valid for comparison across ethnic groups ( Gallagher et al., 1996; USDHHS, 2000). A limitation of the BMI measure is that it does not provide information about body fat distribution, which has been identified as an independent predictor of health risk ( National Institute of Health, 1993; USDHHS, 2000). However, until a better measure of body fat is developed, BMI will be used as a proxy to screen for overweight and obesity.

3

Generally terms used to define the intensity of physical activity are light, moderate, hard or vigorous, and very hard or strenuous. A common classification is to use MET (metabolic equivalent task) values. One MET is the number of kilocalories expended in 1 hour of resting. Often, activities with a MET value below 3.0 are considered light activities; easy walking and regular housework are examples. Activities with MET values of at least 3.0 but less than 6.0 are often classified as moderate; examples are brisk walking, heavy gardening, and calisthenics. Activities with MET values of at least 6.0 but less than 12.0 are often called vigorous, and include jogging, running, swimming, aerobics, and bicycling. Strenuous or very hard activities-such as bicycle or foot racing, speed skating, and competitive cross-country skiing-have MET values of 12.0 or higher.

4

A drink is defined as 0.54 ounces of ethanol, which is the approximately the amount of alcohol in 12 ounces of regular beer, 5 ounces of wine, or 1.5 ounces of 80'proof distilled spirits.

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Several behaviors that exert a strong influence on health are reviewed in this section: tobacco use, alcohol consumption, physical activity and diet, sexual practices, and disease screening. Although epidemiologic data on the relationships between these behaviors and various health outcomes were available in the early 1980s, many refinements in knowledge have occurred since then.

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Healthcare as an influence on health - IV

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Healthcare as an influence on health - IV

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Healthcare's quality deals with the patient, and their cooperation toward the provider. If it all goes smoothly, your doctor will have no troubles helping you reach your desired outcome of good health.

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The affects of media on an individual's health has its' pros and cons. There has been a recent study where media has negatively affected behavioral health. Television and other types of digital viewing has been strongly linked to an increase in sleep disorders, asthma, mood disorders, etc...

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Children and adolescents spend more time with media than they do in any other activity except for sleeping - an average of seven hours a day. The vast majority of young people have access to a bedroom television, computer, the Internet, a video-game console and a cell phone.

In a review article, " Health Effects of Media on Children and Adolescents," published in the April issue of Pediatrics (appearing online March 1), researchers review recent research on the effects of media on the health and well-being of children and adolescents. Research has found that media can influence children's beliefs and behaviors in terms of violence and aggression, sex, substance abuse, obesity and eating disorders. Heavy television viewing has been linked with attention-deficit disorder and diminished academic performance, as well as hypertension, asthma, sleep disorders, mood disorders, psychological distress and depression. Media can also be a positive influence and teach children empathy, tolerance toward people of other races and respect for their elders, as well as convey important public health messages.

Study authors provide recommendations for parents, health care practitioners, schools, the entertainment industry and the government to increase the benefits and reduce the harm that media can have.

The American Academy of Pediatrics is an organization of 60,000 primary care pediatricians, pediatric medical subspecialists and pediatric surgical specialists dedicated to the health, safety and well-being of infants, children, adolescents and young adults. For more information, visit.

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Children and adolescents spend more time with media than they do in any other activity except for sleeping - an average of seven hours a day. The vast majority of young people have access to a bedroom television, computer, the Internet, a video-game console and a cell phone.

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Heredity has an influence on health through your parent's genetics. For example, one of your parents may have a genetic disease while the other is healthy. When they produce a child, that child will have a 50% probability of having a child with the disease.

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You might already have a general understanding about heredity that - it is carried from parents to their children and will affect the health and physical characteristics of children. But do you want to know more about what is heredity and how it affects the health and other physical and mental characteristics? Then we answer in detail to your questions.

We know that genes play an important role in determining our physical characteristics. But to know how genes work, let's get into some biology facts. Cells in human body contain a substance called deoxyribonucleic acid (DNA). DNA is wrapped together to form structures called chromosomes.

What is Heredity?

Most cells in human body have 23 pairs of chromosomes, thus making a total of 46. But, individual sperm and egg cells have only 23 unpaired chromosomes. A child receives half of chromosomes from mother's egg and the other half from father's sperm cell. A male child receives an X chromosome from his mother and a Y chromosome from his father. Females get an X chromosome from each parent.

Genes are sections or segments of DNA that are carried on chromosomes and determine specific human characteristics, such as health conditions, hair color, etc. Some characteristics come from a single gene, whereas others come from gene combinations.

Heredity is the passing of genes from one generation to the next. It is what that determines what you are today. Heredity plays an important role, but your environment also influences your abilities and interests.

DNA contains four chemicals - Adeninine, Guanine, Thymine, Cytosine - that are strung in patterns on extremely thin, coiled strands in the cell. The DNA patterns are the codes for manufacturing proteins - chemicals that enable the body to work and grow. Genes hold the instructions for making protein products. As your cells duplicate, they pass this genetic information to the new cells. Genes can be dominant or recessive. Dominant genes show their effect even if there is only one copy of that gene in the pair. For a person to have a recessive disease or characteristic, the person must have the gene on both chromosomes of the pair.

Cells can sometimes contain variants in the information in their genes. This is called gene mutation. It often occurs when cells are aging or have been exposed to certain chemicals or radiation. Fortunately, cells usually recognize these mutations and repair them by themselves. Sometimes, however, they can cause ill health such as some types of cancer. If the gene mutation exists in egg or sperm cells, children can inherit the mutated gene from their parents.

Heredity and Health

There are more than 4,000 diseases that are caused by genetic variants. But, having a genetic mutation that may cause disease doesn't mean that a person will definitely get that disease. Because you inherit a gene from each parent, having one disease gene may not cause any problems. Normal gene can allow your body to make the normal protein.

People probably carry from 5 to 10 variant or disease genes in their cells. Problems actually arise when the disease gene is dominant or when the same recessive disease gene is present on both chromosomes of a pair. Problems also occur when several variant genes interact with each other - or with environment - that increase susceptibility to diseases.

If a person carries the dominant gene for a disease, he or she will usually have the disease, and each of the person's children will have a 50% chance of inheriting the gene and getting the disease. Diseases caused by a dominant gene include achondroplasia. Marfan syndrome and Huntington disease.

People who have one recessive gene for a disease are called carriers. They don't usually have the disease because they have a normal gene of that pair that can do the job. When two carriers have a child together, however, the child has a 25% chance of getting the disease gene from both parents and in turn getting the disease. Cystic fibrosis, sickle cell anemia, and Tay-Sachs disease are caused by such recessive disease genes.

Some recessive genetic variants are carried only on the X chromosome, which means that usually only guys can develop the disease because they have only one X chromosome. Girls have two X chromosomes, so they would need to inherit two copies of the recessive genes to get the disease. X-linked disorders include the bleeding disorder, hemophilia and color blindness.

Sometimes when an egg and sperm unite, the new cell may get too many or too few chromosomes. Most children born with Down syndrome, which is associated with mental retardation, have an extra chromosome number 21. In some cases, people who are concerned that they might carry certain variant genes can undergo genetic testing, so they can learn their children's risk of having a disease. Pregnant women can also have tests done to see if the fetus they are carrying have certain genetic illnesses or not. Genetic testing usually involves taking a sample of someone's blood, skin or amniotic fluid, and checking it for signs of genetic diseases or disorders.

Gene Therapy offers Solutions

Gene therapy is a promising new field of medical research. In gene therapy, researchers try to supply copies of healthy genes to cells with variant or missing genes so that the healthy genes will take over. Viruses are often used to carry the healthy genes into the targeted cells because many viruses can insert their own DNA into targeted cells.

But there are many problems with gene therapy. Scientists haven't yet identified every gene in the human body and what each one can do. Huge scientific efforts like 'The Human Genome Project' and related projects have recently completed a map of the entire human genome. But it will take many more years to find out what each gene does and possible interactions between them. For most diseases, scientists don't know if and how genes play a role. And, there are major difficulties inserting the normal genes into the proper cells without causing problems for the rest of the body.

There are also concerns that people might try changing genes for ethically troubling purposes. No one knows what the long-term effects of that kind of change would be. Still, for many people who have genetic diseases, gene therapy holds the hope. Let us wish that with the advances in gene therapy, present and future generations would be able to live better and healthier lives.

Therefore, heredity does affect our physical as well as mental health. Some of the hereditary diseases are:

Diabetes

Hypertension

Cancer

Stroke

Heart diseases

Down syndrome

Depression

Schizophrenia

Cystic fibrosis

Sickle-cell anemia

Polydactyly

Autism

Inflammatory Bowel Syndrome

Obesity

Huntington's disease

Besides the heredity factor, the environmental factor also plays an important role in these diseases. With proper precautions, one might avoid some of the diseases which are passed on because of genes. Basic preventions and lifestyle changes can help one avoid certain hereditary diseases and help us live quality life. Look at the positive aspect, you don't have to spend a huge amount of money on health care.

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You might already have a general understanding about heredity that - it is carried from parents to their children and will affect the health and physical characteristics of children. But do you want to know more about what is heredity and how it affects the health and other physical and mental characteristics?

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Aspects of culture can affect an individual's health through a variety of different ways.  For instance, perceptions on health is different than how others view it, others will have different beliefs on the causes of illness and disease.

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Key points

Culture is a pattern of ideas, customs and behaviours shared by a particular people or society. It is constantly evolving.

The speed of cultural evolution varies. It increases when a group migrates to and incorporates components of a new culture into their culture of origin.

Children often struggle with being ‘between cultures’– balancing the ‘old’ and the ‘new’. They essentially belong to both, whereas their parents often belong predominantly to the ‘old’ culture.

One way of thinking about cultures is whether they are primarily ‘collectivist’ or ‘individualist’. Knowing the difference can help health professionals with diagnosis and with tailoring a treatment plan that includes a larger or smaller group.

The influence of culture on health is vast.  It affects perceptions of health, illness and death, beliefs about causes of disease, approaches to health promotion, how illness and pain are experienced and expressed, where patients seek help, and the types of treatment patients prefer.

Both health professionals and patients are influenced by their respective cultures. Canada’s health system has been shaped by the mainstream beliefs of historically dominant cultures.

Cultural bias may result in very different health-related preferences and perceptions. Being aware of and negotiating such differences are skills known as ‘cultural competence’. This perspective allows care providers to ask about various beliefs or sources of care specifically, and to incorporate new awareness into diagnosis and treatment planning.

Demonstrating awareness of a patient’s culture can promote trust, better health care, lead to higher rates of acceptance of diagnoses and improve treatment adherence.

What is culture?

Culture is the patterns of ideas, customs and behaviours shared by a particular people or society. These patterns identify members as part of a group and distinguish members from other groups. Culture may include all or a subset of the following characteristics:¹

Given the number of possible factors influencing any culture, there is naturally great diversity within any cultural group. Generalizing specific characteristics of one culture can be helpful, but be careful not to over-generalize.

ethnicity

language

religion and spiritual beliefs

gender

socio-economic class

age

sexual orientation

geographic origin

group history

education

upbringing

life experience

Culture is:

dynamic and evolving,

learned and passed on through generations,

shared among those who agree on the way they name and understand reality,

often identified ‘symbolically’, through language, dress, music and behaviours, and

integrated into all aspects of an individual’s life.²

Case examples

Compare the two stories that follow and imagine how each child might react differently to a similar situation, such as a problem at school, a criticism, or their mother becoming ill.

A great escape?

A 10-year-old Sudanese girl lived for 3 years as the less-cared-for child with an aunt who had 4 other children. Her mother, a Sudanese journalist, was persecuted and jailed after having written politically sensitive articles in a national newspaper. One night, her mother suddenly arrived to take the child away under cover of darkness. They walked all night and slipped across the border. Once across, they lived in a refugee camp for 2 years, facing various difficulties because they had no male family member to protect them.  Eventually, with assistance from the United Nations High Commissioner for Refugees and the Canadian government, they made their way to Canada as Government Assisted Refugees. The mother has since been diagnosed with post-traumatic stress disorder, and although she is being treated, she has difficulty functioning in the day-to-day and adapting to life in Canada.  The daughter quickly became her mother’s interpreter and caregiver. She appeared well-adapted, did well in school, was motivated to help her mother, smiled and spoke easily and was very intent on learning English.  No one thought to ask how she had dealt with her own story.

Turning the page

A 10-year-old daughter of a Sudanese schoolteacher in a wealthy area of Khartoum left the country with her mother under the protection of a diplomat during a stable period. This diplomat had arranged visas to Germany and provided a car with diplomatic license plates and a skillful driver, who drove them to the safest airport. There, they boarded a small plane that connected to a pre-arranged flight to Frankfurt, Germany.  Mother and daughter lived for two years in Frankfurt, the child attending school while her mother worked as a tutor. They rented a room from a friend. Ultimately, they decided to migrate to Canada to join extended family in Toronto, who sponsored them. The mother remarried after arriving in Canada.

Learning points:

Diversity exists within any single culture.

The adaptation of a child can be influenced by numerous factors in addition to culture (personal, family, migration-related, social, environmental).

Any negative effects of such factors may be well hidden by the child.

A child may compensate for a parent’s debility.

Migration trajectories vary in significant ways.

Culture: The hidden and the obvious

Culture has been described as an iceberg, with its most powerful features hidden under the ocean surface as illustrated in Figure 1. Explicit cultural elements are often obvious but possibly less influential than the unrecognized or subconscious elements providing ballast below.

Figure 1: Elements of culture

Source: Slide 6, Introduction to clinical cultural competence. Clinical Cultural Competency Series. Courtesy of the Centre for Innovation & Excellence in Child & Family Centred Care at SickKids Hospital.

The cultural continuum

Culture is commonly divided into two broad categories at opposite ends of a continuum: collectivistic or individualistic. Most cultures fall somewhere between the two poles, with characteristics of both. Also, within any given culture, individual variations range across the spectrum. Still, being familiar with characteristics of collectivistic and individualistic cultures is useful (see Table 1) because it helps practitioners to ‘locate’ where a family falls within their cultural continuum and to personalize patient care.

Collectivistic and individualistic cultures can give rise to different views on human health, as well as on treatment, diagnoses and causes of illness. Depending on where a patient ‘fits’ along their cultural continuum, including  extended family in discussions about disease origin, diagnosis and treatment may be helpful. Consent for certain diagnostic and therapeutic interventions may be needed from extended family members.

Table 1: Characteristics of collectivistic and individualistic cultures

Collectivistic

Individualistic

Focus on “we”

Focus on “I”

Promote relatedness and interdependence

Value autonomy

Connection to the family

View ability to make personal individual choices as a right

Value respect and obedience

Emphasize individual initiative and achievement

Emphasize group goals, cooperation and harmony

Lesser influence of group views and values, and in fewer aspects of life

Greater, broader influence of group views and values

Source: Adapted from slide 11, Cross-cultural communication.Clinical Cultural Competency Series. Courtesy of the Centre for Innovation & Excellence in Child & Family Centred Care at SickKids Hospital, Toronto.

Indecision or decision-making?

You might expect a 26-year-old mother to make a decision regarding her child’s treatment alone. Having just completed an evaluation of her 6-year-old, you present 2 options for investigation. The mother shies away from making a firm decision and answers you in vague terms. She seems to speak in circles, almost dancing around the choice, even after hearing all the information needed to decide which care path to follow. You know that she has finished high school, and note impatiently that you have already spent an hour with her. The following week she returns. You worry about the length of the visit and falling behind with other patients. To your surprise, she is decisive. She confides, with some prompting, that she discussed treatment options with her husband and mother-in-law, and together they have arrived at the best solution. She can now confidently pursue the investigation of her child’s condition.

Learning points:

The health care provider’s culture is individualistic, while the mother’s is more collectivistic. The mother needed to consult before she could provide an answer.

Communication styles differ. The mother feared shaming the provider by doubting advice, but also didn’t feel comfortable admitting that she would have to bring the choice home to decide.

Education level is not an issue: it’s a red herring.

Impact of culture on health

Health is a cultural concept because culture frames and shapes how we perceive the world and our experiences. Along with other determinants of health and disease, culture helps to define:

How patients and health care providers view health and illness.

What patients and health care providers believe about the causes of disease. For example, some patients are unaware of germ theory and may instead believe in fatalism, a djinn (in rural Afghanistan, an evil spirit that seizes infants and is responsible for tetanus-like illness), the 'evil eye', or a demon. They may not accept a diagnosis and may even believe they cannot change the course of events. Instead, they can only accept circumstances as they unfold.

Which diseases or conditions are stigmatized and why. In many cultures, depression is a common stigma and seeing a psychiatrist means a person is “crazy”.

What types of health promotion activities are practiced, recommended or insured. In some cultures being “strong” (or what Canadians would consider “overweight”) means having a store of energy against famine, and “strong” women are desirable and healthy.

How illness and pain are experienced and expressed. In some cultures, stoicism is the norm, even in the face of severe pain. In other cultures, people openly express moderately painful feelings. The degree to which pain should be investigated or treated may differ.

Where patients seek help, how they ask for help and, perhaps, when they make their first approach. Some cultures tend to consult allied health care providers first, saving a visit to the doctor for when a problem becomes severe.

Patient interaction with health care providers. For example, not making direct eye contact is a sign of respect in many cultures, but a care provider may wonder if the same behaviour means her patient is depressed.

The degree of understanding and compliance with treatment options recommended by health care providers who do not share their cultural beliefs. Some patients believe that a physician who doesn’t give an injection may not be taking their symptoms seriously.

How patients and providers perceive chronic disease and various treatment options.

Culture also affects health in other ways, such as:

Acceptance of a diagnosis, including who should be told, when and how.

Acceptance of preventive or health promotion measures (e.g., vaccines, prenatal care, birth control, screening tests, etc.).

Perception of the amount of control individuals have in preventing and controlling disease.

Perceptions of death, dying and who should be involved.

Use of direct versus indirect communication. Making or avoiding eye contact can be viewed as rude or polite, depending on culture.

Willingness to discuss symptoms with a health care provider, or with an interpreter being present.

Influence of family dynamics, including traditional gender roles, filial responsibilities, and patterns of support among family members.

Perceptions of youth and aging.

How accessible the health system is, as well as how well it functions.

What health professionals can do

Health care providers are more likely to have positive interactions with patients and provide better care if they understand what distinguishes their patients’ cultural values, beliefs and practices from their own.

The following suggestions may help you care for and communicate with patients who are new to Canada:3,4

Consider how your own cultural beliefs, values and behaviours may affect interactions with patients. If you suspect an interaction has been adversely affected by cultural bias – your own or your patient’s – consider seeking help.

Respect, understand and work with differing cultural perceptions of effective or appropriate treatment. Ask about and record how your patients like to receive health care and treatment information.

Where needed, arrange for an appropriate interpreter.

Listen carefully to your patients and confirm that you have understood their messages.

Make sure you understand how the patient understands his or her own health or illness.

Recognize that families may use complementary and alternative therapies. For appropriate, specific conditions, remind them that complementary and alternative medicine use can delay biomedical testing or treatment and potentially cause harm.

Try to ‘locate’ the patient in the process of adapting to Canadian culture. Assess their support system. What are their language skills?

Negotiate a treatment plan based on shared understanding and agreement.

In Canada, health information is typically print-based. Find out whether a patient or family would benefit from spoken or visual messaging for reasons of culture or limited literacy.

Read more about cultural competence, including specific strategies for delivering culturally competent care. Helpful tools and resources are available from other sources.  SickKids Hospital in Toronto has created a series of e-learning modules. You may wish to complete two modules in particular: Cross-Cultural Communication and Parenting Across Cultures.

Providing health care to different cultural groups

Developing a guide to help health professionals understand cultural preferences and characteristics around the world would be a mammoth undertaking. Also, any such document would be biased by the authors’ own cultural perspectives. Culturally, health professionals in Canada are increasingly diverse, viewing the world and the people they see through many different lenses.

However, health care providers should learn skills around cultural competence and patient-centred care. Such skills can be a compass for exploring, respecting  and using cultural similarities and differences to improve quality of care and patient outcomes.

Above all, remember that:

Cultures are dynamic.

There is huge diversity within any culture.

Even when you think you understand one culture, it will have evolved or you will have identified exceptions.

Resources

Additional Cultural Competency Tools and Resources

Coverdell, Paul D. World wise schools: Culture matters workbook: Thirteen cultural categories; American and host country views compared. Peace Corps.

Juckett, Gregory.  Cross cultural medicine. Am Fam Physician. 2005;72(11):2267-74.

SickKids Hospital (Toronto, Ontario), Centre for Innovation and Excellence in Child and Family-centred Care. The Clinical Cultural Competence E-Learning Modules Series.

Webinar: Mind the Gap! Developing Skills to Navigate Cultural Issues with Newcomer Children, Youth, and Families, September 24, 2014

References

1. University of Minnesota, Center for Advanced Research on Language Acquisition. What is culture?

2. Nova Scotia Department of Health, Primary Health Care Section, 2005. A cultural competence guide for primary health care professionals in Nova Scotia.

3. Kodjo, C. Cultural competence in clinician communication. Paediatri Rev 2009;30(2):57-64.

4. University of Washington Medical Centre. Communication Guide: All Cultures. Culture Clue for Clinicians, 2011.

Editor(s)

Maureen Mayhew, MD

Last updated: March, 2018

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Social Environment as an Influence on Health-BT

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Social Environment as an Influence on Health-BT

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We are first taught the basics of washing our hands before we eat, and brushing your teeth at least two times a day by people around us like our parents or teachers. Our friends and family also have a emotional and mental influence on your health. For example, some of us might be getting peered pressured into doing something by our friends that can effect us mentally. Not fitting in to a society or environment around can influence us emotionally.

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Anthony Van
Calvin Tran
Brian Tran
Iverson Valiente

Period 3