8

Population Perspectives: Understanding Health Trends and Evaluating the Health Care System

The earlier chapters on predisease pathways, positive health, environmentally induced gene expression, and personal ties place strong emphasis on preventing disease, maintaining allostasis, and promoting well-being at levels comparatively proximal to the individual (social, psychological, neurophysiological). The chapters addressing collective properties of communities and inequality focus on more intermediate levels whereby environmental and social structural factors influence health. This chapter focuses explicitly on questions of population health at the macro level. Four primary issues are considered: (1) time trends and spatial variation in population health; (2) accounting for such trends, with particular emphasis given to social and behavioral factors; (3) understanding links between population health and the macroeconomy; and (4) evaluating the health care system. An important crosscutting research priority, among several others delineated below, is to account for population health processes by linking them via multilevel analyses to behavioral, psychosocial, and environmental factors described in earlier chapters.

TIME TRENDS AND SPATIAL VARIATION IN POPULATION HEALTH

Brief summaries are provided below of health trends in life expectancy and disability, both within the United States and in other countries. Changing rates of communicable diseases (e.g., sexually transmitted diseases and tuberculosis) are also examined. Finally, various indicators of child health



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New Horizons in Health: An Integrative Approach 8 Population Perspectives: Understanding Health Trends and Evaluating the Health Care System The earlier chapters on predisease pathways, positive health, environmentally induced gene expression, and personal ties place strong emphasis on preventing disease, maintaining allostasis, and promoting well-being at levels comparatively proximal to the individual (social, psychological, neurophysiological). The chapters addressing collective properties of communities and inequality focus on more intermediate levels whereby environmental and social structural factors influence health. This chapter focuses explicitly on questions of population health at the macro level. Four primary issues are considered: (1) time trends and spatial variation in population health; (2) accounting for such trends, with particular emphasis given to social and behavioral factors; (3) understanding links between population health and the macroeconomy; and (4) evaluating the health care system. An important crosscutting research priority, among several others delineated below, is to account for population health processes by linking them via multilevel analyses to behavioral, psychosocial, and environmental factors described in earlier chapters. TIME TRENDS AND SPATIAL VARIATION IN POPULATION HEALTH Brief summaries are provided below of health trends in life expectancy and disability, both within the United States and in other countries. Changing rates of communicable diseases (e.g., sexually transmitted diseases and tuberculosis) are also examined. Finally, various indicators of child health

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New Horizons in Health: An Integrative Approach (e.g., infant mortality, birth weight, asthma, and other respiratory conditions) are reviewed. Some of these population trends show health improvements across time; others point to increasing health problems. Behavioral and psychosocial factors are implicated in both. A major international data source on health trends is the set of Demographic and Health Surveys. 1 An overarching theme is that the maintenance and improvement of population health have been and continue to be due as much to changes in broader socioeconomic and environmental forces as to more microscopically based biobehavioral science. Understanding and facilitating improvements in socioeconomic conditions, general public health and sanitation, and private and public policies affecting lifestyle have accounted for the bulk of historical changes in population health and very likely recent advances as well (Rose, 1992). Life Expectancy Health varies substantially across and within countries. For example, in 1998 life expectancy in Sierra Leone was 37 years and in Japan it was 80 years. Ninety percent of this range, however, is covered by variation across counties within the United States. The range in life expectancy between females born in Stearns County, Minnesota, and males born in various counties in South Dakota is 22.5 years and extends to 41.3 years when race-specific life expectancy is calculated (WHO, 1999). Over time, life expectancy in the United States has risen from 47 years in 1900 to 78 years in 1995. Table 1 shows the changes in life expectancy at birth between approximately 1910 and 1998 in selected countries. On average, people in richer countries live longer and have higher-quality lives than people in poorer countries. Within countries, at the city, county, and regional levels, people with higher socioeconomic status are on average in better health than those with lower socioeconomic status. As described in Chapter 7, there is also considerable variation across racial and ethnic categories that interacts with socioeconomic status. Disability Recent research shows clearly that chronic disease disability rates are falling in the United States. Figure 1 shows the proportion of the elderly who were disabled in 1982, 1984, 1989, and 1994. Disability is measured as impairments in activities of daily living (ADLs, such as bathing, toileting) 1   The data are available electronically: Demographic and Health Surveys: http://www.measuredhs.com.

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New Horizons in Health: An Integrative Approach TABLE 1 Life Expectancy at Birth for Selected Countries Around 1910 1998 Country Males Females Males Females Australia 56 60 75 81 Chile 29 33 72 78 England and Wales 49 53 75 80 Italy 46 47 75 81 Japan 43 43 77 83 New Zealand a 60 63 74 80 Norway 56 59 75 81 Sweden 57 59 76 81 United States 49 53 73 80 or instrumental activities of daily living (IADLs, such as the ability to perform light household work, use the telephone). The data, from the National Long-Term Care Survey, are for a representative sample of the elderly in each year. The questions are the same in each survey, so the responses give the most accurate available measure of changes in disability over time. a Excluding Maoris. SOURCE: WHO, 1999. In 1982 and 1984 nearly 25 percent of the elderly were disabled. By 1994 disability had declined to 21 percent, a reduction of over 1 percent per year. Furthermore, disability decline is more rapid in the second half of the time period (1989-1994) than the first half (1984-1989). These findings have been confirmed in other data as well (Freedman and Martin, 1998), suggesting the trend is not an artifact of this particular sample. Sketchier evidence suggests that the decline in elderly disability has occurred throughout the developed world. Rates of disability and institutionalization among the elderly in various developed countries, compiled by the Organization for Economic Cooperation and Development (Jacobzone, 2000), have been declining over time in most countries. The decline is only modest in some countries (e.g., the United Kingdom) but is rapid in others (e.g., Japan). The average rate of decline among countries where disability rates are falling is 2.3 percent per year. In only two countries have rates of severe disability increased (Australia and Canada), but even there the rates of institutionalization are falling. Such rates have been falling as well in four of the five countries for which there are time series data, although the decline is generally less rapid than the decline in the rate of severe disability. The exception is France, where institutionalization rates have been increas-

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New Horizons in Health: An Integrative Approach FIGURE 1 Changes in chronic disability among the elderly, 1982-1996. SOURCE: Manton et al. (1997). ing, perhaps reflecting a change in the location of care. Rates of severe disability in France, however, are declining rapidly. Overall, these changes in disability have been sufficiently large for some to argue that health promotion might solve the long-term problems of financing public medical care systems (Singer and Manton, 1998). Behavioral, environmental, and psychosocial factors are, as we argue throughout this report, key routes to such health promotion. Communicable Diseases Sexually transmitted diseases (STDs) and tuberculosis are among the most important communicable diseases in the United States. The incidence of reported chlamydial infections and viral STDs has steadily increased in recent years, while the incidence of gonorrhea has generally declined. Levels of syphilis vary among different population subgroups but have reached record lows since 1995. Vaginal infections such as trichomonas and bacterial vaginosis have probably remained high, although surveillance for these conditions is rudimentary. Table 2 shows the estimated incidence and prevalence of STDs in the United States in 1996. 2 The number of reported cases of gonorrhea has generally declined, 2   The full report is available online from the Kaiser Family Foundation: http://www.kff.org/content/archive/1447/std_rep.pdf.

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New Horizons in Health: An Integrative Approach TABLE 2 Estimated Incidence and Prevalence of Sexually Transmitted Diseases in the United States, 1996 Sexually Transmitted Diseases Incidence Prevalence Chlamydia 3 million 2 million Gonorrhea 650,000 — Syphilis 70,000 — Herpes 1 million 45 million Human papilloma virus 5.5 million 20 million Hepatitis B 77,000 750,000 Trichamoniasis 5 million — Bacterial vaginosis No estimate — HIV 20,000 560,000 starting in the mid-1970s with the introduction of the national gonorrhea control program. A disproportionate share of the decline occurred among older white populations, with infection rates remaining relatively high among minority groups and adolescents. In 1996 the Centers for Disease Control and Prevention (CDC) reported 325,000 new cases of gonorrhea (CDC, 1999b). Because previous investigations have shown that only about half of all diagnosed gonorrhea cases are reported to public health authorities, total gonorrhea infections are estimated to be 650,000 in Table 2. SOURCE: Kaiser Family Foundation, 1998. HIV infection trends in the United States show that in the mid-1970s HIV was transmitted primarily among homosexual and bisexual men. The virus entered the injection-drug-using populations in the 1980s and rapidly spread during that decade. Limited heterosexual transmission occurred until the 1980s. Since 1989 the greatest proportional increase in reported AIDS cases has been among heterosexuals, with this trend expected to continue (Rosenberg, 1995). New methods of estimating HIV incidence and prevalence (Holmberg, 1996) yielded an estimate of 41,000 new HIV infections annually, with between 700,000 and 800,000 prevalent HIV infections. The introduction of protease inhibitors may increase the number of prevalent infections by extending the life of HIV-infected people. Approximately half of the incident and three-quarters of prevalent infections were estimated to have been sexually transmitted. Globally, the incidence of HIV is much higher than in the United States, with an estimated 5.8 million new infections annually and more than 30 million persons currently living with HIV (UNAIDS, 1998). More than 90 percent of the global total has been spread sexually. An important priority for future research is to improve the accuracy of these estimates. Most STD incidence and prevalence estimates are derived

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New Horizons in Health: An Integrative Approach from multiple populations, few of which are representative national surveys, such as NHANES or the national reporting system for AIDS. Establishing nationally representative surveillance for the full range of STDs would help narrow the uncertainty in current estimates. For example, the true number of STD infections could be as low as 10 million or as high as 20 million. The current point estimate is 15.3 million. Potential improvement in the U.S. STD epidemic could ensue from full implementation of the national prevention and control program identified by the expert panel assembled by the Institute of Medicine (Eng and Butler, 1997). The program focuses on improving public awareness and education, reaching adolescents and women, and instituting effective culturally appropriate programs to promote healthy behavior by adolescents and adults. Additional targets are integrating public health programs, training health care professionals, and modifying messages from the mass media. Improved surveillance of STD incidence and prevalence rates will be necessary to document the progress of such initiatives. Turning to global tuberculosis, 6.7 million new cases and 2.4 million deaths were estimated in 1998 (Murray and Salomon, 1998). Based on current tends in implementation of the World Health Organization 's strategy of directly observed, short-course treatment, a total of 225 million new cases and 79 million deaths from tuberculosis are expected between 1998 and 2030 (Murray and Salomon, 1998). Active case finding using mass miniature radiography could save 23 million lives over this period, which underscores the importance of prevention. Single-contact treatments for TB could avert 24 million new cases and 11 million deaths. Combined with active screening, single-contact treatments could reduce TB mortality by 40 percent. In the United States the situation is quite different. Table 3 shows the number of reported cases of TB from 1975 to 1992 (CDC, 1999d). The rapid decline in TB cases from 1975 to 1986 was followed by an increase through 1991. However, in 1998 a total of 18,361 TB cases were reported in the 50 states and the District of Columbia, a decrease of 8 percent from 1997 and 31 percent from 1992, the height of the TB resurgence. The 1998 rate of 6.8 per 100,000 population was 35 percent lower than in 1992 (10.5) but remained above the national goal for 2000 of 3.5 per 100,000 (CDC, 1999a). Considering infectious diseases more generally and on a longer time scale, infectious disease mortality declined during the first eight decades of the twentieth century from 797 deaths per 100,000 people in 1900 to 36 deaths per 100,000 in 1980. The overall general decline was interrupted by a sharp increase in mortality due to the 1918 influenza epidemic. From 1938 to 1952 the decline was particularly rapid, with mortality decreasing by 8.2 percent per year. Pneumonia and influenza were responsible for the

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New Horizons in Health: An Integrative Approach TABLE 3 Tuberculosis Cases, Case Rates, Deaths, and Death Rates per 100,000 Population: United States, 1975-1998   Tuberculosis Cases Tuberculosis Deaths   Percent Change   Percent Change Year Number Rate a Number Rate Number Rate a Number Rate 1975 33,989 15.9 — — 3,333 1.6 -5.1 -5.9 1976 32,105 15.0 -5.5 -5.7 3,130 1.5 -6.1 -6.3 1977 30,145 13.9 -6.1 -7.3 2,968 1.4 -5.2 -6.7 1978 28,521 13.1 -5.4 -5.8 2,914 1.3 -1.8 -7.1 1979 27,669 12.6 -3.0 -3.8 2,007 b 0.9 b -31. b -30.8 b 1980 27,749 12.3 +0.3 -2.4 1,978 0.9 -1.4 0.0 1981 27,373 11.9 -1.4 -3.3 1,937 0.8 -2.1 -11.1 1982 25,520 11.0 -6.8 -7.6 1,807 0.8 -6.7 0.0 1983 23,846 10.2 -6.6 -7.3 1,779 0.8 -1.5 0.0 1984 22,255 9.4 -6.7 -7.8 1,729 0.7 -2.8 -12.5 1985 22,201 9.3 -0.2 -1.1 1,752 0.7 +1.3 0.0 1986 22,768 9.4 +2.6 +1.1 1,782 0.7 +1,7 0.0 1987 22,517 9.3 -1.1 -1.1 1,755 0.7 -1.5 0.0 1988 22,436 9.1 -0.4 -2.2 1,921 0.8 +9.5 +14.3 1989 23,495 9.5 +4.7 +4.4 1,970 0.8 +2.6 0.0 1990 25,701 10.3 +9.4 +8.4 1,810 0.7 -8.1 -12.5 1991 26,283 10.4 +2.3 +1.0 1,713 0.7 -5.4 0.0 1992 26,673 10.5 +1.5 +1.0 1,705 0.7 -0.5 0.0 1993 25,287 9.8 -5.2 ‘-6.7 1,631 0.6 -4.3 -14.3 1994 24,361 9.4 -3.7 -4.1 1,478 0.6 -9.4 0.0 1995 22,860 8.7 -6.2 -7.4 1,336 0.5 -9.6 -16.7 1996 21,337 8.0 -6.7 -8.0 1,202 0.5 -10.0 0.0 1997 19,851 7.4 -7.0 -7.5 1,166 0.4 -3.0 -20.0 1998 18,361 6.8 -7.5 -8.1 ... ... ... ... a Per 100,000 population. b The large decrease in 1979 occurred because late effects of tuberculosis (e.g., bronchiectasis or fibrosis) and pleurisy with effusion (without mention of cause) are no longer included in tuberculosis deaths. Ellipses indicate data are not available. SOURCE: Data from CDC, 1999d, Table 1.

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New Horizons in Health: An Integrative Approach largest number of infectious disease deaths throughout the century. Although tuberculosis caused almost as many deaths as pneumonia and influenza early in the century, TB mortality dropped off sharply after 1945. Infectious disease mortality increased in the 1980s and early 1990s in persons aged 25 years and older, due mainly to the emergence of AIDS in 25-to 64-year-olds and to a lesser degree to increases in influenza and pneumonia deaths in persons aged 65 and older. Although most of the twentieth century was marked by declining infectious disease mortality, substantial year-to-year variations and recent increases emphasize the dynamic nature of infectious diseases and the need for preparedness to address them. A considerable effort in this direction was stimulated by a 1992 Institute of Medicine (IOM) report focused on emerging infectious diseases. A wider-ranging multidisciplinary program emphasizing emerging infectious diseases of wildlife, including threats to human health, (Daszak et al., 2000) is notable for its integrative consideration of ecology, pathology, and population biology of host-parasite systems and the emphasis on investigations incorporating individual, population, and environmental perspectives. Child Health In the United States the overall infant mortality rate has decreased rapidly since 1960. Between 1960 and 1994 the rate fell from 24.9 to 8.0 infant deaths per 1,000 live births. Between 1960 and 1992 the infant mortality rate decreased by 69 percent among whites, 62 percent among African Americans, 68 percent among Asians, and 77 percent among Native Americans. Nevertheless, as of 1992 there were considerable racial and ethnic disparities in the infant mortality rate (see also Chapter 7). The African American infant mortality rate of 16.8 infant deaths per 1,000 live births was 2.4 times higher than the white rate of 6.9. The Native American rate of 9.9 infant deaths per 1,000 live births was second highest, and the Asian rate of 4.8 per 1,000 live births was lowest. Two other trends of concern in the health of children that are implicated in longer-term negative health consequences are the rate of low-birth-weight babies and the teen birth rate. Nationally, the percent of live births weighing less than 5.5 lbs. (a standard indicator of low birth weight) was 6.8 in 1985 and 7.4 in 1996. The number of births to teenagers between 15 and 17 per 1,000 females in this age category rose from 31 in 1985 to 34 in 1996. There was substantial variation across states in these two statistics. For example, in 1996 the low-birth-weight rate was 4.8 percent in New Hampshire, 9.9 percent in Mississippi, and 14.3 percent in the District of Columbia. The teen birth rate ranged from 15 in New Hampshire to 52 in Mississippi and 79 in the District of Columbia (Annie E. Casey Foundation, 1999).

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New Horizons in Health: An Integrative Approach When assessing the health of children, it is important to examine the prevalence of chronic health conditions. Children with persistent health problems are more likely to miss school and require medical assistance and follow-up. Such chronic problems also pose difficulties for the parents, who may experience emotional stress, often lose days from work, and incur additional medical expenses associated with recurrent medical visits and follow-up care. The circumstances of both children and their parents in this kind of persistent difficult environment contribute to the predisease pathways described in Chapter 2. Asthma is the most common chronic disease of childhood, affecting an estimated 4.8 million children. It is one of the leading causes of school absenteeism, accounting for over 10 million missed school days each year (U.S. DHHS, 1996). In addition, managing asthma is expensive and imposes financial burdens on the families of people who have it. In 1990 the cost of asthma to the U.S. economy was estimated to be $6.2 billion, with the majority of the expense attributed to medical care. A 1996 analysis found the annual cost of asthma to be $14 billion (CECS, 1998). Table 4 shows the number of children per 1,000 children aged 0-17 in 1993 with a diversity of chronic conditions (NCHS, 1993). Over the past 20 years, respiratory conditions have been the most prevalent type of chronic health problem experienced by children aged 0-17. Rates for most of the chronic health problems identified in Table 4 were fairly constant during that time period, with the exception of chronic respiratory conditions, which showed sizable increases from 1982 to 1993. For example, rates of chronic bronchitis rose from 34 per 1,000 children in 1982 to 59 per 1,000 in 1993 (a 76 percent increase). Similarly, rates of asthma rose 79 percent, going from 40 cases per 1,000 in 1982 to 72 cases per 1,000 in 1993 (NCHS, 1982-1993). Risk Factors In a widely cited paper McGinnis and Foege (1993) showed that unhealthy behaviors and environmental exposures were the “actual causes of death” that accounted for 50 percent of all U.S. mortality. Heading the list of causes were tobacco (19 percent), diet/activity patterns (14 percent), and alcohol (5 percent). Smoking has transformed lung cancer from a virtually unknown disease in 1900 to the leading cause of cancer deaths in 1999, accounting with environmental tobacco smoke and interactions with other exposures (e.g., radon) for more than 90 percent of lung cancer deaths each year. Smoking is also the leading cause of chronic obstructive pulmonary disease and chronic bronchitis and emphysema (Warner, 2000). The prevalence of smoking has dropped from 45 percent in 1963, the year prior to publication of the Surgeon General's report on smoking and health (U.S.

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New Horizons in Health: An Integrative Approach DHEW, 1964), to 25 percent in 1997 (CDC, 1999c). Based on projections of the demographics of smoking, even in the absence of stronger tobacco control education and policy, and assuming no change in youth initiation of smoking, prevalence should continue to fall over the next 20 years, leveling off at approximately 18 percent of adults (Mendez and Warner, 1998; see also). TABLE 4 Selected Reported Chronic Conditions, Number per 1,000 Persons, by Age: United States, 1993 Type of Chronic Condition All Ages Under 18 Years Selected conditions of the genitourinary, nervous, endocrine, metabolic, and blood-forming systems: Goiter or other disorders of the thyroid 16.3 1.9 Diabetes 30.7 1.5 Anemias 15.4 8.6 Epilepsy 5.3 5.4 Migraine headache 43.3 13.2 Neuralgia or neuritis, unspecified 2.7 0.2 Kidney trouble 15.1 4.7 Bladder disorders 15.8 3.4 Diseases of the prostate 8.0 – Disease of female genital organs 21.0 2.6 Selected circulatory conditions:     Rheumatic fever with or without heart disease 7.9 1.2 Heart disease 83.6 20.3 Ischemic heart disease 28.1 0.3 Heart rhythm disorders 35.9 14.9   8.7 0.4   19.5 14.1   7.6 0.5 Other selected diseases of the heart, excluding hypertension 19.6 5.0 High blood pressure (hypertension) 108.3 3.1 Cerebrovascular disease 13.2 1.0 Hardening of the arteries 7.0 – Varicose veins of the lower extremities 30.0 0.6 Hemorrhoids 39.8 0.2 Selected respiratory conditions: Chronic bronchitis 54.3 59.3 Asthma 51.4 71.6 Hay fever or allergic rhinitis without asthma 93.4 56.7 Chronic sinusitis 146.7 79.6 Deviated nasal septum 7.0 0.7 Chronic disease of the tonsils or adenoids 11.0 26.4 Emphysema 7.6 0.7 SOURCE: Data from NCHS, 1993.

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New Horizons in Health: An Integrative Approach DHEW, 1964), to 25 percent in 1997 (CDC, 1999c). Based on projections of the demographics of smoking, even in the absence of stronger tobacco control education and policy, and assuming no change in youth initiation of smoking, prevalence should continue to fall over the next 20 years, leveling off at approximately 18 percent of adults (Mendez and Warner, 1998; see also). Of adult Americans, 24.7 percent were smokers in 1997 (CDC, 1999c). Although a greater percentage of men smoke than women (27.6 percent and 22.1 percent, respectively), the gap between the two genders has declined gradually over time. Racial and ethnic differences in smoking prevalence are substantial, ranging from 16.9 percent for Asians and Pacific Islanders to 34.1 percent for Native Americans and Native Alaskans. Smoking rates vary substantially by age, with prevalence declining in the fourth and subsequent decades of life. Smoking cessation, the principal determinant of the decline in prevalence with age, rises significantly with age. An important research challenge for demographers is the development of more effective ways of assessing smoking initiation. In the 1999 Monitoring the Future Survey, 34.6 percent of high school seniors had smoked within the previous 30 days. 3 The comparable figures for tenth and eighth graders were 25.7 percent and 17.5 percent, respectively. The interpretive problem with these figures, from the point of view of health risk, is that, while 30-day prevalence rates were rising during the 1990s, measures of regular and heavy smoking (e.g., half a pack or more per day) were not. While the latter clearly point to increased health risk, it is unclear what risks follow from the 30-day prevalence rates among youth. Since the inception of the antismoking campaign in 1964, the most notable change in smoking prevalence is by education class. In 1965, the year following the first Surgeon General's report, less than 3 percentage points separated the prevalence of smoking among college graduates (33.7 percent) from that of Americans who did not graduate from high school (U.S. DHHS, 1989). By 1997 prevalence among college graduates had fallen by nearly two-thirds to 11.6 percent. Among people without a high school diploma, in contrast, prevalence had fallen by only one-sixth (to 30.4 percent; CDC, 1999c; Warner, 2000). Although considerable speculation has been put forth about the reasons for this disparity, this is an important future research direction, directly linked to those of and Chapter 7, where the social and behavioral sciences are particularly prominent. Dietary factors and sedentary activity patterns together account for at least 300,000 deaths each year (McGinnis and Foege, 1993). Dietary fac- 3   The data are available electronically: .

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New Horizons in Health: An Integrative Approach life are more likely to retire early than are people who do not experience a serious illness at that age (Smith, 1999), which reduces their lifetime earnings. Adolescents who are diagnosed with depression are less likely to get a college degree than are those not so diagnosed (Berndt et al., 2000) and thus are likley to earn less over their lifetime. Advances in interventions that alleviate these health burdens could substantially reduce the public-sector financial burden. In any case, a central economic challenge facing the public sector is how to prepare for an aging society. THE HEALTH CARE SYSTEM The medical system is an important part of health. Indeed, public discussion about health focuses to an overwhelming degree on access to medical care. Understanding how the system operates and how well it works is therefore a central issue for behavioral and social research. We address three issues of concern in current and future evaluations of the health care system: (1) the effects of medical care on improving health, (2) the managed care debate, and (3) growing public interest in alternative medicine. Effectiveness of Medical Care Research shows mixed results regarding the value of the medical system. We illustrate these issues with medical care for the elderly, but the same issues apply to those who are not elderly, for example, asthma in children or disease transmission in teens and young adults. Some research highlights the positive effect of medical care on improving health. As noted above, one of the leading theories for reduced disability among the elderly is that such advances result from medical technology improvements. This view is widespread among biomedical researchers: medical advances, they believe, embodied in new technologies lead to significant health gains. Other research, however, highlights the apparently low return from additional medical spending. For example, Medicare spending varies by a factor of two among areas of the country, with no apparent differences in health outcomes (CECS, 1998). Research on heart attack patients shows that intensive procedures are used up to five times more frequently in the United States than in Canada, but mortality rates are the same in the two countries (Rouleau et al., 1993; Mark et al., 1994; Tu et al., 1997). Indeed, within the United States, people who live close to high-tech hospitals receive intensive services more frequently than people who live farther away from such hospitals, but again health outcomes are essentially the same (McClellan et al., 1994). The value of additional medical spending is therefore unclear and is a needed avenue for future research.

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New Horizons in Health: An Integrative Approach Several explanations have been proposed for the disparate or conflicting findings about whether medical care has high or relatively low returns. One hypothesis is that medical care is valuable but is often applied inappropriately. For example, areas that spend a lot on medical care may simply give the technology to more people than will benefit from it. Much evidence supports the view that medical care is frequently wasted. Studies of medical procedure use in the United States, for example, find that a significant number of patients receiving high-tech services should not receive them on the basis of published clinical studies (Chassin et al., 1987; Winslow et al., 1988a, b; Greenspan et al., 1988). Other evidence is less supportive, however, finding that rates of inappropriate procedure use are no greater in areas with high usage rates compared to areas with lower usage rates. Reconciling conflicting evidence about the value of medical care is an important priority for future research. It also has been proposed that preventive care is used in inverse proportion to more intensive medical services, so that people not receiving intensive treatment still have good outcomes. This is claimed to explain the lack of outcome differences between the United States and Canada. Canada has more complete coverage for outpatient pharmaceuticals than does the United States. Increased use of pharmaceuticals may allow Canadians to live longer, offsetting the survival advantage that comes from more intensive procedure use in the United States. The distinction between over-time and point-in-time analysis must also be considered in evaluating the effectiveness of medical care. Many studies that find that medical care has a high rate of return compare treatments at different points in time, that is, before and after a particular technology is available. For example, changes in the treatment of heart attacks during the 1980s are associated with large increases in survival (Cutler and Sheiner, 1998). The same is true for care of low-birth-weight infants between 1950 and 1990 (Cutler and Meara, 2000). In contrast, studies that find that medical care has a low rate of return generally look at the use of the same treatment in different localities at the same point in time. Differences in use at a point in time may be more wasteful than increased use over time. An increasing number of cost-effectiveness analyses of preventive strategies and alternative therapies are appearing. For example, Trussell et al. (1997) analyzed the economic benefits of adolescent contraceptive use utilizing information from a national private payer data base and from the California Medicaid program. Their study estimated the costs of acquiring and using 11 contraceptive methods appropriate for adolescents, treating associated side effects, providing medical care related to an unintended pregnancy during contraceptive use, and treating sexually transmitted diseases (STDs) and compared them with the costs of not using a contraceptive method. The average annual cost per adolescent at risk of unintended

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New Horizons in Health: An Integrative Approach pregnancy who uses no method of contraception is $1,267 ($1,079 for unintended pregnancy and $188 for STDs) in the private sector and $677 ($541 for unintended pregnancy and $137 for STDs) in the public sector. After one year of use private-sector savings from adolescent contraceptive use ranged from $308 for an implant designed to prevent ovulation to $946 for the male condom. Public-sector savings rose from $60 for the implant to $525 for the male condom. Both the use of male condoms with another method and the advance provision of backup emergency contraceptive pills provided additional savings. Shifting to an example of the cost effectiveness of cholesterol-lowering therapies, Prosser et al. (2000) found that ratios varied according to different risk factors. Specifically, incremental cost effectiveness ratios were found for primary prevention with a low fat, low cholesterol diet (National Cholesterol Education Program step I), ranging from $1,900 per quality-adjusted life-year (QALY) gained to $500,000 per QALY depending on risk subgroup characteristics. Primary prevention with a statin (a cholesterol-lowering drug) compared with diet therapy was $54,000 per QALY to $1.4 million per QALY. Secondary prevention with a statin cost less than $50,000 per QALY for all risk subgroups. Primary prevention with a step I diet seems to be cost effective for most risk subgroups defined by age, sex, and the presence of additional risk factors. It may not be cost effective for otherwise healthy young women. In addition, primary prevention with a statin may not be cost effective for younger men and women with few risk factors, given the option of secondary prevention and of primary prevention in older age groups. Secondary prevention with a statin seems to be cost effective for all risk subgroups and is cost saving for some high-risk subgroups. As a further illustration, an economic evaluation was conducted alongside a randomized controlled trial of two lifestyle interventions (e.g., education and video to assess risk factors, program plan for risk factor behavior change) and a routine care (control) group to assess cost effectiveness for patients with risk factors for cardiovascular disease (Salkeld et al., 1997). The cost per QALY for males ranged from $152,000 to $204,000. Further analysis suggested that a program targeted at high-risk males would cost $30,000 per QALY. The lifestyle interventions had no significant effect on cardiovascular risk factors when compared to routine patient care. There remains insufficient evidence that lifestyle programs conducted in general practice are effective. Resources for general-practice-based lifestyle programs may be better spent on high-risk patients who are contemplating changes in risk factor behaviors. Alternatively, the extensive literature on the economics of coronary heart disease prevention (Brown and Garber, 1998) suggests that many programs (e.g., exercise, smoking cessation, de-

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New Horizons in Health: An Integrative Approach tection and treatment of hypertension, cholesterol reduction) are highly cost effective. While these examples are illustrative of the kinds of studies needed on a wider scale, it is important to underscore that such inquiries can have substantial impact on the quality of care provided by a diverse range of practitioners. In addition, errors in specification of therapeutic programs, mistakes made during surgical procedures, improper diagnoses, and faulty laboratory procedures are being documented on an increasingly broad scale. Such lines of inquiry are important for understanding the behavior of health care providers as a function of economic and organizational constraints placed on them. It will be equally important to turn solid research findings into improved practices. This will require effective communication and ongoing dialogue between the research community and practitioners. Cultural factors also play a prominent role here, since patients of different ethnic backgrounds approach—or do not approach—health care providers with very diverse views of health and wellness (Kleinman, 1981, 1989). Also important for the future will be analyses of data on medical treatments matched to health outcomes. Such data are now becoming widely available through Medicare and large insurers. The Managed Care Debate Public concern about managed care is intense, as recent legislative efforts to enact a patients' bill of rights attest. Research about how managed care actually affects medical practice, however, is limited. Changes in insurance coverage for nonelderly Americans between 1980 and 1996 were dramatic. In 1980, 92 percent of the population had traditional indemnity insurance, with 8 percent in health maintenance organizations (HMOs). In 1996 only 3 percent of the population remained in unmanaged fee-for-service plans. An additional 22 percent were in managed fee-for-service plans. The bulk of the population was enrolled in various types of managed care programs, including traditional HMOs, preferred-provider organizations (PPOs), and point-of-service plans (POSs). The spread of managed care is largely responsible for the reduced rate of growth of medical spending in the 1990s (Cutler and Sheiner, 1998). This trend has provoked fundamental questions. How does managed care save money: by restricting the number of services provided or by cutting payments for services? That is, managed care might affect the delivery of medical care in two ways: by altering the access rules (determining which people have access to medical providers) and the payment rules (determining reimbursement to providers). People with managed care insurance typically have more restrictive access to providers and high-tech care than do people in traditional indemnity insurance. On the other hand,

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New Horizons in Health: An Integrative Approach people with managed care insurance generally have lower costs than do those with indemnity insurance. The central issue is how health outcomes are affected by managed care. A second issue is whether the rise of managed care affects the diffusion of medical technology and whether that will be good or bad. Understanding the full incentives of managed care is difficult and requires the participation of both economic and medical expertise, for example, in understanding exactly how physicians are paid and what services they are able to provide. Sociological and psychological input is necessary as well. For example, physicians treated as employees of a managed care insurer may behave differently than physicians who see themselves as running their own practice. The degree to which managed care affects physician practice may depend on how it changes physicians' perceptions of their role in the medical system as much as it changes their actual ability to provide certain services. Research has yet to explore this issue. Managed care might also have a direct effect on the extent to which providers acquire and use particular technologies. Several recent papers argue that managed care has reduced the diffusion of hospital-based technologies, including diagnostic scanners and some surgical procedures (Cutler and Sheiner, 1998; Baker and Spetz, 1999). If such changes in access translate into change in utilization, it could have important implications for the long-term value of the medical sector. Research on this issue is just beginning as well. In summary, the phenomenal change in the medical system encompassed by managed care, coupled with the availability of rich sources of data, make this topic a prime candidate for future research. Understanding the economic and health consequences of managed care has great import for informing public policy pertaining to the health care system. Alternative Medicine Therapies A large and expanding component of the U.S. health care system involves alternative medicine therapies, functionally defined as interventions neither taught widely in medical schools nor generally available in U.S. hospitals (Eisenberg et al., 1993). In 1990 a national survey of alternative medicine prevalence, costs, and patterns of use demonstrated that alternative medicine has a substantial presence in the U.S. health care system. Since that time, an increasing number of insurers and managed care organizations have offered alternative medicine programs and benefits. Correlatively, the majority of U.S. medical schools now offer courses on alternative medicine (Wetzel et al., 1998; Eisenberg et al., 1998). In a follow-up national survey conducted in 1997 (Eisenberg et al., 1998), data were assembled that allowed for quantitative assessment of

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New Horizons in Health: An Integrative Approach trends in alternative medicine use over that time period. Use of at least one of 16 alternative therapies investigated increased from 8 percent in 1990 to 42.1 percent in 1997. The therapies increasing the most included herbal medicine, massage, megavitamins, self-help groups, folk remedies, energy healing, and homeopathy. In both the 1990 and 1997 surveys alternative therapies were used most frequently for chronic conditions, including back problems, anxiety, depression, and headaches. The percentage of users paying entirely out of pocket for services provided by alternative medicine practitioners did not change significantly between 1990 (64.0 percent) and 1997 (58.3 percent). Extrapolations to the U.S. population suggest a 47.3 percent increase in total visits to alternative medicine practitioners, from 427 million in 1990 to 629 million in 1997, thereby exceeding total visits to all U.S. primary care physicians. An estimated 15 million adults in 1997 took prescription medications concurrently with herbal remedies and/or high-dose vitamins (18.4 percent of all prescription users). Estimated expenditures for alternative medicine professional services increased 45.2 percent between 1990 and 1997 and were conservatively estimated at $21.2 billion in 1997, with at least $12.2 billion paid out of pocket. This exceeds the 1997 out-of-pocket expenditures for all U.S. hospitalizations. Total 1997 out-of-pocket expenditures relating to alternative therapies were conservatively estimated at $27 billion, which is comparable to the projected 1997 out-of-pocket expenditures for all U.S. physician services. The large economic impact of alternative medicine clearly demands research attention. Specifically, substantial resources should be devoted to clinical and integrated biological and social science research to provide rigorous understanding of the role of these interventions in the health of the U.S. population. This is important for establishing the credibility of claims for alternative medicine therapies. Part of this line of inquiry should include research on why placebos sometimes work and for whom. More generally, the broad area of mind/body relationships and their neurobiological underpinnings represent a vast research opportunity for the future. A useful example of the kind of knowledge development and synthesis that are needed is the elaborate study of meditation and neurobiology by Austin (1998). The new NIH trans-institute initiative that recently established five mind/body centers around the United States constitutes a further important step in this direction. FUTURE DIRECTIONS IN POPULATION SURVEYS Several sources of data and methodologies will be essential in addressing the agendas described above. Perhaps the most basic need is for enhanced longitudinal population-level surveys. Such surveys should be enhanced in three ways:

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New Horizons in Health: An Integrative Approach They need to be linked to administrative records on the receipt of medical care and on work histories. Such linkage is vital because individuals will not recall all of the medical care they have received nor their earnings records. Surveys need to be supplemented with community-level variables to determine how the social and economic environments affect individual behavior. They need to have basic biological markers. Incorporating indicators of cumulative physiological risk (e.g., allostatic load) as standard components of longitudinal survey protocols would provide a basis for the integrative analyses recommended throughout this report. Augmenting longitudinal surveys with physical health examinations would be of enormous value, as the Framingham Study has shown. Data from medical systems are also essential. Health insurers in the United States and other countries have access to unparalleled data on medical treatments and outcomes. These data can be used to study the value of the medical system. They can also address questions about behavior and community-level variables because they often contain detailed information on health conditions and medical treatments at the community level. Finally, we stress the role for international comparative work in answering the full range of population health questions discussed in this chapter. Economic, social, and medical systems differ greatly across countries, and thus international work is a natural laboratory for analysis. RECOMMENDATIONS We urge NIH to invest new resources in research to identify linkages between population health trends and the behavioral, environmental, and psychosocial factors emphasized in preceding chapters. Priority should be given to the following topics: multilevel analyses necessary to advance rigorous explanations for the observed dynamics of the health of populations, giving particular emphasis to behavioral risk and protective factors and to psychosocial and environmental influences on aggregate-level health changes; development of projection methodologies to provide defensible scenarios of how health changes will affect society in the future; continue and expand multi-institute support of research on child health, particularly asthma and its costs, both economic (e.g., parental absence from work) and social (e.g., family burden, child development); increase support for research on the reciprocal relationships between

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New Horizons in Health: An Integrative Approach population health and the macroeconomy , together with linkages to community and individual-level dynamics as discussed in prior chapters; develop new initiatives to investigate the conflicting findings about whether medical care has high or low returns for whom , when , and how . Importantly , data on medical treatments must be matched to health outcomes; increase support for research on the economic and health costs or benefits of managed care (of central importance are studies that clarify how health outcomes are affected by managed care); establish new trans-institute priorities to evaluate the effectiveness of alternative medicine therapies as well as to clarify their economic impact . REFERENCES Annie E. Casey Foundation . 1999 Kids Count Data Book, 1999 ( Baltimore : Annie E. Casey Foundation ). Austin J. 1998 Zen and the Brain( Cambridge MA : MIT Press ). Baker L , Spetz J. 1999 “Managed care and medical technology growth” NBER Working Paper 6894 ( Cambridge MA : National Bureau of Economic Research ). Barker DJ. 1997a “The fetal origins of coronary heart disease” Acta Paediatrica422/suppl. : 78-82 . Barker DJ. 1997b “Maternal nutrition, fetal nutrition and disease in later life” Nutrition 13/9 : 807-13 . Berndt ER , Koran LM , Finkelstein SN , Gelenberg AJ , Kornstein SG , Miller IW , Thase ME , Trapp GM , Keller MB. 2000 “Lost human capital from early-onset chronic depression” American Journal of Psychiatry 157/6 : 940-947 . Bloom BR. 1999 “The future of public health” Nature 402/suppl. 2 December : C63-C64 . Brown AD , Garber AM. 1998 “Cost effectiveness of coronary heart disease prevention strategies in adults” Pharmacoeconomics 14/1 : 27-48 . CECS (Center for Evaluative Clinical Sciences) , Dartmouth Medical School . 1998 Dartmouth Atlas of Health Care ( Chicago : American Hospital Publishing ). CDC (Centers for Disease Control and Prevention) . 1999a “Progress toward the elimination of tuberculosis—United States, 1998” Morbidity and Mortality Weekly Report48/33 : 732-736 . CDC (Centers for Disease Control and Prevention) . 1999b Tracking the Hidden Epidemics: Trends in the STD Epidemics in the United States ( Atlanta : Centers for Disease Control and Prevention ). CDC (Centers for Disease Control and Prevention) . 1999c “Cigarette smoking among adults—United States, 1997” MMWR Morbidity and Mortality Weekly Report48 : 993-996 . CDC (Centers for Disease Control and Prevention) . 1999d Reported Tuberculosis in the United States, 1998( Atlanta : Centers for Disease Control and Prevention ). Chassin MR , Kosecoff J , Park RE , Winslow CM , Kahn KL , Merrick NJ , Keesey J , Fink A , Solomon DH , Brook RH. 1987 “Does inappropriate use explain geographic variations in the use of health care services? A study of three procedures” Journal of the American Medical Association 258/18 : 2533-2537 . Costa DL. 1998 “Understanding the twentieth century decline in chronic conditions among older men” Working Paper 6859 ( Cambridge MA : National Bureau of Economic Research ) .

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