We used to think we knew how to make populations healthier: start by safeguarding the quality of air, water, and food and providing for the proper disposal of human and industrial waste; next, ensure the availability of adequate medical care. More recently, we came to know the importance of healthy forms of behavior -- abstaining from smoking, drinking alcohol in moderation and not before driving an automobile, eating wisely, participating in regular physical activity, and engaging in prudent sexual practices. But recent information has complicated our understanding of health. Even when one controls (as best one can) for differences in medical care and behavioral risk factors, huge gradients persist in overall and disease-specific mortality rates according to income, educational status, job category, and neighborhood. How and why these gradients occur and what, if anything, can be done to reduce them are some of the critical questions facing people who are interested in the health of the public, the genetic revolution notwithstanding. Lisa Berkman and Ichiro Kawachi of the Harvard School of Public Health are leaders in expanding our view of health, first with their important book entitled Social Epidemiology (New York: Oxford University Press, 2000) and now with Neighborhoods and Health. In Social Epidemiology, they provided a comprehensive review of the ways in which social context influences behavior as well as a broad range of health outcomes. Why are income and educational status so important? How do factors such as jobs, discrimination, neighborhoods, and social cohesion influence health, and what methods can be used to improve our understanding of these complex relations? Neighborhoods and Health drills deeper into one variable -- neighborhoods. Using the same format as they used in Social Epidemiology, Kawachi and Berkman have assembled a multidisciplinary group of authors that includes epidemiologists, sociologists, demographers, statisticians, clinicians, and medical geographers. The book of 15 chapters is divided into four parts. The first two chapters review previous research, making a strong case regarding the way in which neighborhoods influence health (e.g., through differential exposure to health care, stressors, employment, transportation, stores, recreation, crime, "incivilities" such as litter and graffiti, policing, environmental hazards, and social networks). A particularly sobering finding is that the age-, race-, and sex-adjusted relative risk of death associated with living in a poor area is 1.7. The next section (chapters 3 through 8) focuses on the methodologic complexities of research on neighborhoods. In short, this kind of research requires complex, multilevel analytic techniques that may prove difficult to translate for policy analysts. Chapters 9 through 11 summarize evidence that links neighborhoods to specific health outcomes -- infections, infant health, and asthma. We learn, for example, that mothers in poor neighborhoods in Boston who keep children indoors because they fear violence thereby increase their children's likelihood of exposure to respiratory viruses that trigger asthma attacks. The final section illustrates crosscutting themes such as residential segregation according to race and class, social interactions, aging, and the relevance of neighborhood to social policy. The finding that was the most striking to me was the quantification of segregation according to race. The probability that a poor person lives in a high-poverty neighborhood (with a poverty rate of at least 40 percent) is only 6 percent among whites, as compared with 22 percent among Hispanics and 34 percent among blacks. It is difficult to generalize from Neighborhoods and Health, because much of the research comes from cities in the eastern United States, and the populations are mostly black, with minimal inclusion of groups such as Hispanics and Asians. This is especially important, since these groups have such different health profiles from blacks of similar economic and educational status. Who should read this book? People who are unfamiliar with the subject should review the early parts and the final four chapters to get a sense of the book's relevance and complexity. Clinicians caring for indigent populations can expand their understanding of the effects of neighborhoods on health by skimming through chapters 9 through 11. People who wish to work in the field need to be immersed in the difficult chapters on methodology. The book contains its own summary: "The field . . . is still at an early stage. . . . Much remains to be done before this research fulfills its potential in improving population health." Steven A. Schroeder, M.D.
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"The methodological insights and specific research findings displayed in the book Neighborhoods and Health
signal an important advance in epidemiology. This book summarizes much of the recent progress that has been made in studies that use aggregate or area-wide measurements. Overall, this book has much to offer. The authors themselves are clearly aware of the complexities, unsolved problems, and numerous challenges that confront anyone who wants to assess quantitatively the impact of social and geographic units on health."--American Journal of Epidemiology