Historically speaking, human health has been a tale of ever-shifting horizons. For much of the distant past, health was equivalent to short-term survival in the face of food scarcity, predators, and pestilence. With gains in agriculture, sanitation, and the growth of community, length of life was extended somewhat. Later, the scientific revolution transformed health into a biological realm that was primarily the purview of medical fields, at least in Western and economically developed cultures. The past century has witnessed dramatic gains in longevity, thanks to unprecedented advances in diagnosing, treating, and preventing disease, along with unimaginable gains in technology that facilitate understanding health at molecular, cellular, and genetic levels. Still, there remains significant distance to travel in the journey toward optimal human health. The horizon before us is one in which health encompasses not only the workings of biology, the brain, and the body but also the human mind, its thoughts and feelings, human actions and behavior, as well as the nature of social ties, friendships, family, and community life.
With this vision before us, we call for a new era of research and practice at the National Institutes of Health (NIH) that integrates biomedical and social behavioral fields of inquiry to promote the nation's health. Increasing evidence documents the role of behavioral, psychological, social, and environmental factors as causes of death. 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. Moreover, modern scientific tools afford far-reaching opportunities for unraveling mechanistic processes (e.g., environmentally
induced gene expression, overload of physiological systems) through which behavioral and psychosocial factors contribute to illness and disease. In counterpoint to such maladaptive biobehavioral interactions, people's positive daily practices (e.g., getting proper nutrition, engaging in physical activity, avoiding cigarettes, alcohol, and drugs), along with the quality of their social relationships, psychological outlooks, and community supports are emerging as key ingredients to health and well-being over the life course. In short, the behavioral and social sciences are unavoidably implicated in making sense of both illness and good health, although much as yet is unknown about how these effects occur, particularly in terms of what can be done to avoid their deleterious impacts as well as promote their salubrious benefits for ever larger segments of the population.
This chapter sets the stage for the proposed new era of integrative health research. We first briefly review the history of the behavioral and social sciences at NIH and then describe the specific charge to the committee and our interpretation of this charge.
The integrative approach to health is the overarching theme of this report. In support of it, we revisit the distinguished intellectual history of those who have called for such bringing together of multiple levels of analysis. In numerous corners of science, the need to embark on new inquiries that put the disciplines together is a growing refrain. This synthesis—the move toward “consilience” (Wilson, 1998)—is particularly essential if we are to achieve comprehensive understanding of how good health at the level of the individual and of society is realized or lost. Much has been learned, and will continue to be gained, by focusing on single diseases and single mechanistic processes, but we bring into high relief the reality that many illnesses co-occur, as do many risk factors (behavioral and biological). What is needed, thus, are new studies that delineate the biopsychosocial pathways through which converging processes contribute to diverse health outcomes.
Each of the following chapters is broad and integrative in scope. Collectively, the chapters comprise key elements required for integration, from molecular, cellular, and genetic levels through behavioral, psychological, social, and environmental levels to multiple health outcomes. Stated otherwise, the chapters embody what the committee deemed critical influences that are essential to understanding the pathways to health.
THE CONTEXT: BEHAVIORAL AND SOCIAL SCIENCES AT THE NATIONAL INSTITUTES OF HEALTH
The behavioral and social sciences are increasingly recognized as vital contributors to understanding and improving the nation's health. In this regard, it is important to note the long history of behavioral and social
science research at NIH. For example, the National Heart Institute, predecessor of the National Heart, Lung, and Blood Institute, was founded in 1948 and funded its first behavioral science research grant in 1955. The study was focused on psychological factors related to high blood pressure and coronary heart disease. The National Cancer Institute, established in 1937, also has an extensive behavioral research program emphasizing cancer prevention and control. The historical roots of this broad agenda reside in the mandate of the National Cancer Act, passed by Congress in 1971. More generally, many of the institutes have longstanding and well-developed behavioral and social science programs. Trans-institute initiatives with linkages to basic biology are also appearing with increasing frequency, such as the recent call for proposals on socioeconomic status and health as well as the recent establishment of five new mind/body centers around the country.
At the same time, the behavioral and social sciences have limited presence at some institutes or are seen as peripheral to primary agendas. Also, when considered at all, behavioral, psychological, and social priorities are sometimes restricted to a narrow focus on their role as risk factors for particular disease outcomes. To facilitate the growth and development of these important fields, Congress established the Office of Behavioral and Social Sciences Research (OBSSR) at NIH in 1995. A central message of OBSSR, and the background for this report, is that behavioral, psychosocial, and environmental factors have broad significance at NIH and are fundamental to comprehensive understanding of diverse disease etiologies as well as to positive health promotion.
THE CHARGE TO THE COMMITTEE
In 1999 the director of OBSSR requested assistance from the National Research Council (NRC) to develop a research plan to guide NIH in supporting areas of high priority in the social and behavioral sciences. Three principal goals shaped the OBSSR planning efforts: (1) enhancement of behavioral and social sciences research and training, (2) integration of biobehavioral interdisciplinary perspectives across NIH, and (3) improvement of communication between those conducting scientific research and the general public. The OBSSR sought to use the priorities requested from the NRC as a framework within which to implement these goals.
Within the NRC and its Commission on Behavioral and Social Sciences and Education (CBASSE), the Board on Behavioral, Cognitive, and Sensory Sciences chose to undertake a brief, highly focused study in response to the OBSSR request. The board established our committee to carry out this activity. Drawing on the existing social behavioral research base, the committee was asked to frame its discussion around four key areas:
behavioral and social risk and protective factors;
biological, behavioral, and social interactions as they affect health;
behavioral and social treatment and prevention approaches;
basic behavioral and social processes.
In addition, the committee was encouraged to consider the following issues in shaping its response: (a) health problems for which behavioral and social sciences research might offer solutions with respect to treatment and prevention, (b) areas of scientific opportunity in the behavioral and social sciences where a substantial investment might pay large dividends in the near future, (c) the public's chief health concerns.
Finally, the committee was asked to give special attention to collaborative research, interdisciplinary projects, and trans-institute initiatives that would have general application to broad areas of illness and health and would be sensitive to perspectives of the various NIH institutes. In considering this charge, the committee decided not to undertake a thorough review of all extant social behavioral research at NIH, a behemoth task beyond the scope of this report. Rather, guided by its original charge, the committee set itself to charting promising future directions where the behavioral and social sciences are well poised to connect with extant biomedical and/or intervention agendas (at individual, community, or population levels). Importantly, the members decided this could best be accomplished not by organizing the report around specific diseases or institutes, thereby following the current structure of NIH, but by providing a broader, more integrative approach.
It should be noted that the behavioral and social sciences, as applied to health, have never been organized around specific diseases. This is understandable, given that many behavioral risk factors (e.g., smoking, obesity, sedentary lifestyles, risky sexual practices) not only themselves co-occur but are also precursors to multiple physiological risk factors and multiple adverse health outcomes. The integrative approach thus gives much greater emphasis to the empirical realities of co-occurring risk and comorbidity, both of which are better understood with an integrative approach. The committee's essential task was to identify key components of a comprehensive approach as to how health outcomes, broadly defined, come about.
It is important to underscore three aspects of the committee's approach to its task. First, the committee covered a huge scientific territory in a very limited period of time and yet was able to quickly achieve consensus regarding the overall structure of the report and the content of the chapters. This efficient exchange was greatly facilitated by the prior experience of committee members in carrying out multidisciplinary science. There was little, if any, disciplinary turf guarding or vying for preeminence; instead, the tar-
geted objective from the moment the work began was to find the best framework for integrating multiple fields and agendas.
Second, the committee had no intention of producing an exhaustive set of future research opportunities. Indeed, it is doubtful that such a comprehensive formulation could be developed by any committee. There was also no attempt made to cover extant programs of every institute within NIH. Stated otherwise, the committee was faced with the unavoidable requirement for selectivity. Nonetheless, the integrative research opportunities that it formulated do represent promising trans-institute initiatives, but they are put forth only as illustrations of the kinds of studies for which there could be substantial scientific payoff and opportunity to improve the public's health. Many vibrant areas of current NIH research are, therefore, inevitably missing from the chapters that follow. We state explicitly that what is not in the report is by no means an indirect message about low-priority status.
Third, the committee wrote this report with the scientific audience at NIH, and not the general public, in mind. Our goal is to communicate a new vision of integrative health to those who will carry out the future research and practice. A critical feature of such integration is the need to demonstrate command of complex areas and their interrelationships. Thus, we have not eliminated all technical details but tried to write about them so as to maximize their accessibility to our audience.
THE INTEGRATIVE APPROACH TO HEALTH
In the past 25 years, the study of human health has included a distinguished, but neglected, intellectual tradition put forth by numerous investigators, who saw the need for broad integrative frameworks that capture complex pathways to illness and disease. Engel (1977), for example, formulated a multifactorial model of illness, later subsumed under the rubric “biopsychosocial” that views illness as a result of interacting systems at cellular, tissue, organismic, interpersonal, and environmental levels. As a result, the study of every disease must include the individual, the body, and the surrounding environment as essential components. Lipowski (1977) and Fava and Sonino (2000) set the scope, mission, and methods of psychosomatic medicine as also involving interrelated facets of biological, psychological, and social determinants of health and disease. Around the same time, Henry and Stephens (1977) advanced a sociobiological approach to medicine and health that integrated not only biological, psychological, social, and physical environmental factors but also presented comparative studies of pathways to illness and disease between rodents, nonhuman primates, and humans.
More recently, Worthman (1999) combines human biology, life history
theory, and epidemiology to consider variations in human development, giving particular emphasis to the role of hormones in the physiological architecture of the life course. Weiner (1998) offers “notes” toward a comprehensive evolutionary theory that integrates the roles of physical, social, environmental, and psychological factors in the maintenance of good health and the pathogenesis of disease. Keating and Hertzman (1999) assemble a cohesive set of essays that are designed to provide an “integration of knowledge about the determinants of health and human development.” McEwen and Stellar (1993) introduce a multisystem approach to the cumulative physiological toll exacted by adverse behavioral, psychological, social, and environmental influences over the life course. This formulation of cumulative physiological risk is linked to unfolding interactions between genetic and environmental influences over time.
At an even broader level of thinking, E.O. Wilson has adapted and expanded on William Whewell's 1840 notion of consilience (Wilson, 1998, p. 8) as a “jumping together” of knowledge by the linking of facts and factbased theory across disciplines to create a common groundwork of explanation. Wilson emphasized that “a unified system of knowledge is the surest means of identifying the still unexplored domains of reality. It provides a clear map of what is known, and it frames the most productive questions for future inquiry.” Wilson's integration includes not only the full range of scientific disciplines but also the humanities and, as such, represents even more distant horizons for promoting health and well-being.
These perspectives collectively provide conceptual background to the theme of integration that guides this report and our related efforts to characterize pathways to multiple health outcomes. The time for this larger synthesis of scientific disciplines in pursuit of human health has come.
KEY INFLUENCES ON PATHWAYS TO HEALTH
Our task as a committee was one of identifying key elements that comprise an integrated and comprehensive approach to health. When the behavioral and social sciences are emphasized and linked to health, one is automatically led away from a disease-specific emphasis and into a view of multiple pathways to multiple outcomes. For example, smoking is a behavior linked to lung cancer, chronic bronchitis and emphysema, and cardiovascular diseases. Quality of social relationships, in turn, has been linked to cardiovascular diseases, later-life cognitive functioning, and recovery from a variety of illnesses. In both examples, and numerous others documented in this report, there is a need for understanding the pathways underlying these coarse-grained linkages. Moreover, full understanding of pathways requires a long time horizon that includes genetic predispositions and early life antecedents that contribute to later-life health and disease. It
requires a multilevel view of life histories in which, for example, gene expression is seen as a dynamic process linked to psychosocial experience and community-level structures.
A behavioral and social science emphasis also leads naturally to a focus on prevention. This is not to detract from the social behavioral contributions to disease etiology, clinical medicine, and the organization and operation of the health care system. However, when the objective is to understand the mechanisms that explain how a range of health outcomes come about, it is appropriate and meaningful to identify health-promoting practices that can prevent or delay illness and disability and reduce the demand for curative health services.
With these observations in mind, the committee identified 10 priority areas for research investment that would integrate the behavioral, social, and biomedical sciences at NIH. These are briefly noted below, with emphasis on why they were selected and what they contribute to the larger mosaic of health.
Predisease Pathways: identification of early and long-term biological, behavioral, psychological, and social precursors to disease. This priority is intended to broaden the time horizons that guide research on disease etiology as well as underscore agendas that may lead to early preventive strategies.
Positive Health: identification of biological, behavioral, and psychosocial factors that contribute to resilience, disease resistance, and wellness. This priority draws attention to the need for greater emphasis throughout NIH on the biopsychosocial factors that help individuals maintain or regain good health throughout the life course.
Environmentally Induced Gene Expression: emphasis on the need to connect modern advances in genetic analysis to environmental factors (behavioral, psychological, social) to clarify their interactions in understanding positive and negative health outcomes.
Personal Ties: the growing body of literature that connects the social world to health and calls for greater explication of the biobehavioral mechanisms by which relationships with significant others (family, friends, co-workers) influence health and disease.
Collective Properties and Healthy Communities: greater emphasis on neighborhood and community-level variables, such as residential instability or social cohesion, and how they contribute to positive or negative health practices and outcomes.
Inequality and Health: builds in the growing awareness that socioeconomic hierarchies, racism, discrimination, and stigmatization are linked with differences in health and illness and calls for greater understanding of
the mechanisms through which these effects occur and how they can be reversed.
Population Health: greater understanding of macro-level trends in health status, how the macroeconomy and population health are linked, and the performance of the health care system.
Interventions: expansion of the scope and effectiveness of behavioral, psychosocial, and biological strategies for improving health, including multilevel (individual, family, organizational, population) initiatives.
Methodology: emerges from the recognition that new measurement techniques and study designs are required to link information across diverse levels of analysis (molecular, cellular, behavioral, psychosocial, community) and across time.
Infrastructure: refers to the need for future structures and resources to maintain long-term study populations and train new generations of scientists to integrate health-related knowledge across multiple disciplines.
The scope of these priorities is expansive and integrative, with each encompassing wide areas of research. Some represent phenomena at the individual level, while others deal with macro-level (e.g. population) issues. The chapters that follow elaborate each of these priorities and identify principal recommendations associated with them. Collectively, they comprise the integrated pathway approach to health that is the guiding theme of this report.
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