Introduction

As child survival programs continue to achieve their goals of reducing infant and child mortality, the age structure and overall health status of the populations of most developing countries are changing. A decline in fertility in many parts of the world has resulted in a shift toward an older population. With an increasing proportion of the population falling into the adult and elderly age groups, the epidemiological profiles of developing countries increasingly reflect the diseases and health problems of adults rather than of children. In particular, chronic and degenerative diseases, and accidents and injuries, are becoming more important causes of death. In most countries, this process has been accelerated by a more rapid reduction in infant and child mortality rates than those of adults. This shift in demographic and disease profiles, often referred to as the epidemiological transition, is currently under way in most developing countries. The transition occurs at different paces in different places, depending on the rate of fertility changes, the distribution of risk factors that contribute to the incidence of disease, and the health system’s ability to respond to the changing epidemiological profile.

Although scientists are beginning to understand better some of the trends in the changing disease and mortality patterns, policymakers need to know how to use this information to make decisions about the priorities for the health sector. To emphasize the importance of using demographic and epidemiologic data in decision making, a workshop was convened by the National Academy of Sciences’ Committee on Population and the Institute on Medicine’s Board on International Health, with support from the Office



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The Epidemiological Transition: Policy and Planning Implications for Developing Countries - Workshop Proceedings Introduction As child survival programs continue to achieve their goals of reducing infant and child mortality, the age structure and overall health status of the populations of most developing countries are changing. A decline in fertility in many parts of the world has resulted in a shift toward an older population. With an increasing proportion of the population falling into the adult and elderly age groups, the epidemiological profiles of developing countries increasingly reflect the diseases and health problems of adults rather than of children. In particular, chronic and degenerative diseases, and accidents and injuries, are becoming more important causes of death. In most countries, this process has been accelerated by a more rapid reduction in infant and child mortality rates than those of adults. This shift in demographic and disease profiles, often referred to as the epidemiological transition, is currently under way in most developing countries. The transition occurs at different paces in different places, depending on the rate of fertility changes, the distribution of risk factors that contribute to the incidence of disease, and the health system’s ability to respond to the changing epidemiological profile. Although scientists are beginning to understand better some of the trends in the changing disease and mortality patterns, policymakers need to know how to use this information to make decisions about the priorities for the health sector. To emphasize the importance of using demographic and epidemiologic data in decision making, a workshop was convened by the National Academy of Sciences’ Committee on Population and the Institute on Medicine’s Board on International Health, with support from the Office

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The Epidemiological Transition: Policy and Planning Implications for Developing Countries - Workshop Proceedings of Health of the U.S. Agency for International Development. The workshop was designed to bring together medical experts, epidemiologists, demographers, and other social scientists involved in research on the epidemiological transition and to foster discussion on specific topics. This volume contains papers presented at the meeting that served as a basis for discussion. The papers deal with the quantitative dimension of demographic and epidemiological changes, the processes used in establishing priorities in the health sector, and the roles of governments and families in providing health services. TRANSITIONS IN MORTALITY AND EPIDEMIOLOGIC PATTERNS Changes in mortality structure are the principal outcome indicator by which the epidemiological transition is assessed. Heligman and colleagues (see Heligman et al., Table 8, in this volume) show that whereas 27.3 percent of deaths in less developed regions occurred at ages 50 and above in 1960–1965, 41.9 percent were in that age range in 1980–1985 and 63.0 percent are projected for these ages in 2010–2015. Changing mortality patterns are the product not only of changes in age structure but also of changes in the distribution of risk factors and in age-specific incidence and case-fatality rates of various diseases. In some cases, mortality rates may be declining faster than morbidity and disability rates because better treatments for diseases have reduced their case-fatality rates. Oral rehydration therapy, for example, has not reduced the incidence of diarrheal disease, but has contributed to a reduction in the number of fatalities per case. The populations of developing countries are gradually shifting from environments with greater exposure to infectious diseases (poor water and food quality, unhygienic sanitation practices) to areas with a higher prevalence of risk factors for noncommunicable diseases, such as motor vehicles, unsafe workplaces, and air pollution (Smith, 1990). At the same time, personal behaviors are often changing in ways that increase the chances of developing a chronic disease. The presence of a risk factor does not necessarily imply that a disease will be observed at the level expected on the basis of relationships in developed countries. Nevertheless, epidemiological studies indicate that smoking, hypertension, dietary fat, motor vehicles, occupational hazards, and poverty are among the leading risk factors for death from noncommunicable diseases in developing and developed countries alike. Smoking, for example, although known to be responsible for a number of diseases, has grown in popularity. The increase between 1970 and 1985 in tobacco consumption per adult amounted to 41.6 percent in Africa, 24.0

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The Epidemiological Transition: Policy and Planning Implications for Developing Countries - Workshop Proceedings percent in Latin America and the Caribbean, and 22.1 percent in Asia (Masironi and Rothwell, 1988). Increasing numbers of motor vehicles and unsafe workplaces are risk factors for accidents and injuries. In Brazil, for example, traffic accident death rates are not dissimilar from rates observed in the United States, but they are much higher on both a per-vehicle basis and a per-mile-driven basis than in developed countries (Baker, 1984). Injuries in the workplace tend to be much more common and severe in developing countries (Stansfield et al., 1993). The death rate for factory workers in India was about 50 percent higher than in the United States (Mohan, 1982). Agricultural injury death rates are estimated to be three to eight times higher in developing countries than in developed ones (International Labour Organization, 1988). DATA DEFICIENCIES A number of factors prevent a precise understanding of the epidemiological transition and impede policy formulation. Paramount among these is the absence of good data on mortality. Cause-of-death data either do not exist or are unreliable for most developing countries. Although a number of Latin American countries have high-quality data, no African and very few Asian countries have data on death registration or cause of death. In the absence of reliable data, the cause structure can be estimated from data on the overall level of mortality, by using a model based on the relationship between mortality level and cause-of-death structure in populations with good data (see Bulatao, in this volume). However, this approach raises concern about the relevance of mortality patterns of advanced developing countries or the historical experience of developed countries to the current experience of the world’s poorest countries. As a result, much of the analysis on cause-of-death structure and cause-specific death rates is limited to a few developing countries or subnational populations with reliable data. Another difficulty in studying the epidemiological transition in many countries is that the existing data are not representative of the whole population, but rather often come from a more privileged segment of the population. Urban-based or hospital-based studies may represent one segment of the population, but results from such studies are not readily generalizable. The poorer subpopulations of developing countries are often thought to suffer more from infectious and parasitic diseases, and the wealthier segments are thought to suffer more often from noncommunicable diseases. However, the poor have greater exposure to many of the risk factors associated with communicable and noncommunicable diseases alike. Studies in Brazil, for example, indicate that the highest levels of hypertension, smoking, alcohol use, lack of exercise, and obesity are to be found among those with the lowest educational level (Briscoe, 1990). Cause-specific death

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The Epidemiological Transition: Policy and Planning Implications for Developing Countries - Workshop Proceedings rates for cancer, cardiovascular disease, respiratory disease, and external causes were higher among poor men than wealthy men in Porto Alegre, Brazil (Briscoe, 1990). National-level figures illustrate large-scale changes; to understand the variation that occurs within a country, the population needs to be disaggregated, and the changes taking place within the major subpopulations must be examined. ORGANIZATION OF THIS VOLUME Demographic and Epidemiologic Data Policy and planning implications of the epidemiological transition are based in part on an understanding of how population and mortality structures are likely to change. Larry Heligman, Nancy Chen, and Ozer Babakol provide a projection of changes in population structure over the next 25 years in Latin America, Africa, and developing areas of Asia and Oceania. They describe changes in the number of people, growth, and age structures of populations residing in rural and urban areas, and they examine life-table mortality patterns, numbers dying, and the age structure of deaths in these areas, as well as potential consequences of AIDS on mortality in Africa. A projection of the mortality structure is also useful in planning for the specific types of services that will be needed. Rodolfo Bulatao estimates and projects the cause-of-death pattern for six age groups (0, 1 to 4, 5 to 14, 15 to 44, 45 to 64, and 65 and older), by sex for four calendar years (1970, 1985, 2000, 2015) and by six country groupings (industrial market economies, industrial nonmarket economies, Latin America and the Caribbean, sub-Saharan Africa, the Middle East and North Africa, and Asia and the Pacific). This exercise clearly demonstrates an impending decline in mortality from communicable diseases and the relative emergence of noncommunicable causes. These first two papers provide a quantitative background for subsequent discussions. The projections that achieve worldwide coverage are necessarily rather mechanical exercises in which epidemiologic issues are suppressed. The next two papers introduce additional epidemiological considerations into the analysis of mortality patterns. Henry Mosley and Ronald Gray examine childhood precursors of adult morbidity and mortality, drawing attention to the fact that health insults as early as gestation can influence one’s health status as an adolescent or adult. In developed countries, about 6 to 10 percent of adults die between ages 15 and 60; in developing countries, it is often the case that 25 to 35 percent die during this age interval. The authors suggest that as many as one-third of the preventable deaths in developing countries are the consequences of infection and other conditions acquired during infancy and childhood. These life-cycle connections must be taken

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The Epidemiological Transition: Policy and Planning Implications for Developing Countries - Workshop Proceedings into account in assessing the relative value of health programs directed at children and adults. The shift toward an aging population and the resulting changes in the epidemiological profile call for a better understanding of the complexity of chronic and degenerative diseases. Kenneth Manton and Eric Stallard consider the issues related to projecting morbidity and mortality during the reproductive and postreproductive years by developing a dynamic model based on risk factor regressions and multivariate hazard functions. Combining data sources to produce longitudinal data that include the levels of risk factors in developing countries yields more accurate forecasts than using the generally available data from developed countries. Using examples of active life expectancy and an intervention to reduce risk factors for cardiovascular diseases, the authors illustrate how the model can be employed to project morbidity, mortality, and their associated costs. Setting Priorities in a Changing Epidemiological Environment In determining whether the focus of health investments should be on childhood or adult diseases, a number of indices have been developed that assess the different outcomes based on the types of inputs used. A commonly used index is the healthy years of life saved by specific interventions. Samuel Preston critically examines this index, identifying circumstances in which it yields reliable and unreliable information. A distinction is drawn between interventions that occur over only one year and those that extend into the future. He also discusses whether and how the index accounts for the benefits accrued by those who are not yet born when the intervention is initiated. He argues that population projections can often provide a better vehicle for assessing the consequences of interventions and incorporating other dimensions such as total gain in production or changes in per capita income. José Luis Bobadilla and Cristina Possas examine health policy issues arising from the epidemiological transition in Mexico, Brazil, and Colombia. They develop a framework for health policy decisions based jointly on population dynamics, which provides an idea of the magnitude of the health needs, and on the available health system, which describes the configuration of services available to meet the current level of need. Although it is not possible to formulate a homogeneous health policy agenda for developing countries because each country’s transition is different, the authors offer a set of issues that will help each health system to be more responsive to its population’s needs: redistribute welfare through providing health services, reform the health care model, improve the efficiency and quality of care, and build a national capacity for strategic health planning. The World Summit for Children in 1990 drew attention again to the

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The Epidemiological Transition: Policy and Planning Implications for Developing Countries - Workshop Proceedings continuing high levels of mortality and morbidity among infants and children in developing countries. At that meeting, policy statements were put forward that set goals for reducing mortality, morbidity, and the prevalence of risk factors. Anne Pebley examines these goals, focusing on their demographic plausibility and the potential consequences of achieving them. She raises the issue of whether pursuing numerical goals will draw attention away from the need to focus on durable programs that will have sustained effects on children’s health. The changing health environment raises questions of whether the “child survival” strategy is the best approach for improving children’s health in the 1990s and whether some of the goals can be achieved without improving health care infrastructure. As noted earlier, the demographic and epidemiologic changes that are taking place in developing countries are often aggregated into national-level numbers, but within each population are groups, in widely differing circumstances. The wealthy and poor typically follow different epidemiologic and demographic trajectories. In examining the distributional implications of alternative policy strategies focused on children and adult health, Davidson Gwatkin compares the least healthy segment of the population with the healthiest segment. The comparison is made both for high- and low-mortality scenarios. He demonstrates that paying greater attention to the health problems of adults and the elderly may often exacerbate social inequalities in mortality. Similarly, he shows that the least healthy are likely to benefit more from a reduction in mortality from communicable diseases, whereas a decline in noncommunicable diseases would differentially benefit the healthier segment of the population. Perhaps surprisingly, he shows that a health policy tilt toward adult noncommunicable diseases would be likely to increase inequalities more in low-mortality than in high-mortality developing countries. Providers of Services: Roles of Government, Private Sector, and Families Moving from the debate over whether priority should shift toward adult health, the workshop turned its attention to who should provide services, considering the roles of government, private medicine, and the informal sector. Nancy Birdsall and Estelle James state the case for shifting more of the provision of services to the private sector because of the inefficiencies and inequities associated with government spending. They suggest that informational programs and basic services that cannot be supported in a private, competitive market, such as maternal and child health programs in rural areas, receive public funding. However, services such as hospitals, which presently represent a large percentage of health budgets and serve

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The Epidemiological Transition: Policy and Planning Implications for Developing Countries - Workshop Proceedings only a small portion of the health needs of the population, may warrant privatization, with fees covered by mandated health insurance. Regardless of whether the public or the private sector finances and provides the majority of health services, the informal sector will continue to play a vital role in caregiving. John and Pat Caldwell examine the roles of women, families, and communities in preventing illness and providing health services. They observe that in many parts of the world, mothers are constrained in their ability to care for sick children because of social and economic impediments. Societies that are relatively unaffected by cultural and technological imports often have health beliefs that promote incautious behavior. In some cases, women view child care as a community activity and may be less attentive to their children’s survival because family systems can induce a sense of being powerless to influence events. In some societies, the mother must submit to her mother-in-law or husband regarding the type of care a sick child will receive. In more modern, transitional societies, some women are educated and may take advantage of the health care system. The less educated women are often alienated from the system and, because of their traditional health beliefs, do not use the system as effectively as they could. The authors cite women’s groups and female health visitors as ways of empowering young mothers to care better for themselves and for their children. CONCLUSION Although this volume covers a range of issues related to changing disease profiles in developing countries, it is clearly not an exhaustive account of how societies should adapt to these changes. The papers do not form a cohesive set of policy recommendations; rather they address a set of issues that health planners in developing countries will have to consider as the epidemiological profile of their populations change. In a sense, the adaptation-to-change paradigm is itself rather arbitrary because government policy will play a central role in the pace and direction of future changes. Nevertheless, the widespread declines in fertility and child mortality, both of which contribute to the shifting age structures of developing countries, are not likely to be reversed and have imposed significant changes in the context for thinking about health policy. The demographic changes discussed here will have far-reaching consequences in the social and economic sectors of developing countries. In this report a number of issues related to the health sector’s response are raised. As populations move toward an older age structure, how much emphasis on child survival will be needed? What mechanisms will be used to allocate resources into different health programs? Who will be responsible for providing health care services?

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The Epidemiological Transition: Policy and Planning Implications for Developing Countries - Workshop Proceedings The formulation of health initiatives in this new context involves many considerations, including assessments of the likely cost and effectiveness of specific programs. But there are dangers in prematurely narrowing discussion to technical issues of cost and effectiveness. How governments and families actually behave, how interventions affect various social groups, what long-term effects programs may have on the cohorts that experience them, and even how program effects should be measured and modeled, are questions that need to be addressed before cost-effectiveness calculations can be confidently invoked. This volume represents a contribution to the discussion of these broader issues. REFERENCES Baker, S.P. 1984 The Injury Fact Book. Washington, D.C.: Heath and Company. Briscoe, J. 1990 Brazil: The New Challenge of Adult Health. Washington, D.C.: World Bank. International Labour Organization 1988 Yearbook on Labor Statistics, 48th Issue. Geneva: International Labor Organization. Masironi, R., and K.Rothwell 1988 Tendances et effets du tabagisme dans le monde. World Health Statistics Quarterly 41:228–241. Mohan, D. 1982 Accidental death and disability in India—A case of criminal neglect. Industrial Safety Chronicle (April-June):24–43. Smith, K.R. 1990 The risk transition. International Environmental Affairs 2(3):227–251. Stansfield, S.K., G.S.Smith, and W.P.McGreevey 1993 Injury and poisoning. In D.T.Jamison and W.H.Mosley, eds., Disease Control Priorities in Developing Countries. New York: Oxford University Press for the World Bank.