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Introduction and Overview
Linda Waite
The population of the United States is growing inexorably older. With birth rates
historically low and life expectancy continuing to rise, the age distribution of the
population in the United States is growing steadily older. The portion of Americans who
are 65 or older, which was 8 percent in 1950, reached 12 percent in 2010 and is projected
to be 22 percent by 2050 (United Nations, 2011). This demographic shift is occurring at
a time of major economic and social changes, which have important implications for the
growing elderly population.
The dramatic growth in the percentage of the U.S. population that is older than the
traditional retirement age of 65, for example, is placing an increasing strain on the federal
budget that will almost certainly lead to changes in the Social Security and Medicare
programs, such as increases in the age of eligibility and, perhaps, changes in benefit
levels (see National Research Council and National Academy of Public Administration,
2010). Other changes, such as the move away from defined-benefit towards defined-
contribution retirement plans, changes in some corporate and municipal pension plans as
a result of market pressures, and the 2008 financial crisis precipitated by the crash of the
housing market, all have economic implications for older people. They are also likely to
make it more difficult for certain groups of future retirees to fund their retirements at the
level that they had planned and would like.
Along with these economic changes, the social context within which older
individuals and families function is also changing, affecting, among other things, the
nature of certain types of social relationships and institutions that provide part of the
support infrastructure available to older persons. Demographic and social trends—such
as changes in marriage and fertility preferences, the increasing fragility of unions, the
decline of the intact nuclear family, the increasing amount of time for some young people
to transition to adulthood and the continuing improvements in health and disability at
older ages—all influence the amount and types of support available to older persons and
their need for support.
To deal effectively with the challenges created by population aging, it is vital to
first understand these demographic, economic, and social changes and, to the extent
possible, their causes, consequences and implications. Sociology offers a knowledge
base, a number of useful analytic approaches and tools, and unique theoretical
perspectives that can be important aids to this task. Furthermore, sociology is at its heart
an integrative science, perhaps the discipline that is best suited for “integrating what is
known about human behavior” (Gove, 1995:1197). It concerns itself with how social
systems work and how various social institutions are interconnected, with how micro and
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macro social processed are linked, with how attitudes and values are formed, how they
differ between individuals and groups, and with how realities are socially constructed.
Surprisingly, given the significant potential of the field at this time, interest in the
sociology of aging, as measured solely by the number of grant submissions to the
National Institute on Aging’s Division of Behavioral and Social Research (BSR) has
declined in recent years. In January 2009, a major independent review of BSR
recommended that given the changing nature of the social context, BSR should strive “…
to revitalize the social demography, epidemiology, and sociology portfolios” (Cacioppo
et al., 2009, p. 10) as well as continue research on social networks and their relationship
to health (Suzman, 2010). In response to these recommendations, BSR turned to the
National Research Council (NRC) to evaluate the recent contributions of social
demography, social epidemiology, and sociology to the study of aging and identify
promising new research directions in these subfields. In response, the NRC’s Committee
on Population established an ad hoc Panel on New Directions in Social Demography,
Social Epidemiology, and the Sociology of Aging. Part of the panel’s charge was to
organize a workshop, inviting a series of leading researchers to a two-day meeting to
offer their perspectives on the state of the field and to reflect upon promising future
directions. This volume contains revised versions of the papers presented at that
workshop.
Several themes emerge from this collection of papers. First is the need to grapple
with the changing nature of what is being studied: social institutions, social networks,
social groups, and social forces. These social arrangements vary significantly different
over the life course, from generation to generation, and more problematically, sometimes
even from year to year. Thus, for example, the social factors that influence those adults
who have recently turned 65 are likely to be quite different from those influencing adults
who will turn 65 in two or three decades. The dynamic nature of the subject matter offers
a challenge to sociologists that is not present—or not present to the same degree—in
some other fields. A second theme is the importance of recognizing that aging takes
place across the entire life span, so research questions related to old age outcomes cannot
be properly understood by focusing solely on what occurs during the last stage of life
(Elder, 1999). A third theme is the vast mostly untapped potential for greater integrated
science. Some of the most promising recent research has been done at the interstices
between disciplines when a researcher (or more frequently an inter-disciplinary team of
researchers) has begun to explore how genetic influences and social environments work
in concert to vary the course of aging. Both these last two themes underline the
importance of adopting fruitful theoretical approaches. The choice of inputs, outputs,
mechanisms, and theoretical constructs is crucial to the success of any effort, whether it is
the development of a model, the collection of data, or the design of an intervention trial.
The emergence of these common themes is particularly noteworthy given the
wide variety of approaches and perspectives that the papers in this volume represent. The
authors of these papers come from a range of disciplines, from sociology and
demography to social genomics and public health. A close reading of the papers in this
volume should give readers a better understanding of where the field of the sociology of
aging stands today and where it may be headed fruitfully in the future. In addition, taken
collectively, the papers highlight the broad array of tools and perspectives that can
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provide the basis for further advancing our understanding of aging processes in ways that
can guide policy.
THE CHANGING SOCIAL AND ECONOMIC ASPECTS OF AGING
People’s lives are obviously shaped by the social, political, and economic
contexts into which they are born and within which they grow up, live, form families,
work, and retire. In Chapter 2, Angel and Settersten take up the daunting challenge of
reviewing some of the most critical social and economic changes that are occurring in US
society and what they possibly imply for the well-being of older people.
The authors begin with the observation that the typical life course has changed
over the past few generations. With people living longer healthy lives, “retirement” has
become a time when, at least potentially, people still have the health and the resources to
live life in new, often rewarding ways. At the same time, the three principal phases of the
life-cycle that have traditionally described an individual’s trajectory over the life
course—education followed by work followed by retirement—have been evolving
dramatically. The time in each phase (or box as the authors refer to them) is more
variable than ever before as more people now learn new skills as adults so that their work
years cannot be characterized as a straightforward upward movement through the ranks in
a single profession or even a single company. Instead, with the churning in the economy,
many workers find themselves looking for new jobs at several times in their lives, even as
they approach retirement age. At the same time, marriage and first birth have been
delayed, and the length of time children remain in the education phase or in a pre-work
phase has in some cases been growing longer, which also has important financial
implications for retirement planning.
At the same time, social relationships and institutions have been changing just as
dramatically. As the prevalence of second or even third marriages has risen, mixed
families—with stepparents and stepchildren, ex-spouses and their current spouses and
children, stepsiblings, half-siblings, and so on— have grown in frequency. More children
are born to unmarried mothers, more families are formed by cohabitation, and more men
and women are heading into retirement alone. Families are also more dispersed than they
have traditionally been in the past thanks to increasing mobility for school, work, and
retirement. With new patterns come new ambiguities. In particular, the roles and
obligation associated with taking care of aging parents are no longer as clear-cut as they
once were as part because of the more complex dynamics associated with mixed families.
Patterns of retirement are shifting as well. Age at retirement has fallen for men
over the last 20 years, but the traditional pattern of working full-time until retirement age
and then retiring to a life of full-time leisure is being replaced with a range of other
trajectories, including transitioning to intermittent or part-time work. The choices are
complicated by the uncertainties related to the growing fiscal stresses facing the Social
Security and Medicare systems as an increasingly large percentage of the population
becomes eligible to claim retirement benefits.
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THREE POTENTIAL CONTRIBUTIONS FROM DEMOGRAPHY
In Chapter 3, Hardy provides a global perspective on the demography of
population aging and points to three particularly promising areas of research where
demographers can make real and substantive contributions to furthering our
understanding of population aging. The first is biodemography, with a particular focus on
understanding the interrelations between chronological age, health, and disability. As the
average life expectancy of the population increases, it will be important to understand
how health and disability of the aging population are evolving—a task that will be helped
along by a study of how various biological micro-processes (genetics, cellular biology,
biochemistry, etc.) are linked with the health of individual cohorts and entire populations.
A second area to study is changes in the life course. Each new population cohort
that comes along experiences a different life course, depending on such factors as
education, employment patterns, family structure, gender roles, and social inequality.
Any detailed forecasts of what to expect with an aging population will need to take the
changing life course into account.
A third area where demographers can make important contributions to further our
understanding of the challenges of population aging is in the development of better
forecasts, projections, and simulations that take into account the changes taking place in
successive cohorts as well as the evolving microprocesses to develop a “big picture” of
future populations and their macrolevel features. Such forecasts should be more accurate
than those that do not take these factors into account and thus should help policy makers
prepare more effective ways to anticipate the needs of future populations.
THEORETICAL APPROACHES TO THE SOCIOLOGY OF AGING
One of the contributions of sociology to understanding the issues involved with
aging has been the development of a number of theories whose roots lie in a wide variety
of different approaches to understanding the world around us. Bengtson et al. (1977)
identified 16 different theoretical approaches used in the sociology of aging including, for
example, disengagement theory, which views aging as encompassing an inevitable
process of withdrawing or disengaging from various social roles, activities, and
relationships (Cumming and Henry, 1961) and social exchange theory, which seeks to
explain human interactions and relationships in terms of cost-benefit analyses in which
individuals decide which social actions to take by finding a course that maximizes value
(Blau, 1964). One of the most dominant theoretical approaches has been the life-course
approach which has been used to study how early life events and cumulative processes of
disadvantage help shape later outcomes (Elder, 1999). Not a full-fledged theory as such,
it is more of a guiding principle that “… human development and aging take place across
the entire life-span… adolescent, mid-life, and old age behavior cannot be fully
understood by focusing solely on the specific life-stage in question (Elder, 1999, p. 7).
The life-course perspective reminds us that to understand the differences between
individuals in their later years, we must keep in mind their experiences throughout life,
even reaching back in some cases to include influences before birth. The importance of
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the choice of theoretical approaches in illuminating different aspects of aging, is
illustrated in Chapters 4 and 5.
In Chapter 4 Cagney and colleagues describe one such approach that builds on the
concept of “activity space.” The concept has its roots in three theoretical constructs that
sociologists have found useful in studying aging: social networks, neighborhoods, and
institutions. Social networks—the collections of people that a particular individual
knows and has interactions with—have been shown to be related to a number of health
behaviors and outcomes including smoking behavior and obesity. Generally speaking,
older people with larger, more active networks are likely to be healthier and live longer,
but network sizes and the amount of contact with people in one’s network both tend to
decline with age.
Neighborhoods have also been shown to influence health outcomes among older
adults in various ways. People living in economically disadvantaged neighborhoods, for
example, tend to be at greater risk for disease and have lower life expectancy. At the
same time, there are various health advantages for older adults to living in neighborhoods
with many other older adults nearby.
Institutions, which Cagney and colleagues define as “physical locations where
some form of organized social activity takes place,” play a similarly important role in the
health of older adults, particularly those institutions such as long-term care facilities that
promote greater social integration. Similarly, research has found that involvement in
such institutions as churches, volunteer organizations, recreational facilities, and even
informal gatherings in restaurants or other places have various beneficial effects for aging
adults.
Cagney and colleagues argue that research into the effects of social factors on
older adults can be enriched by applying the theoretical construct of activity space, which
is defined as, in essence, the collection of all locations with which individuals come in
contact during their day-to-day activities. The concept of activity space not only
integrates the more basic concepts of social network, neighborhood, and institution, but it
goes beyond them to include other factors that may play a role in the health of older
adults. Individuals may, for instance, spend much of their time outside of their own
neighborhoods—shopping, visiting family and friends, going to medical appointments,
taking part recreational and other activities, and so on. With its focus on individuals
actual, regular contacts, Cagney and colleagues suggest, the concept of activity space has
the potential to provide a more accurate account of the various influences to which
individuals are exposed. It can also help explain different outcomes in individuals who
may share the same networks, neighborhoods, and institutions. On the other hand,
accumulating data on activity spaces is likely to be more challenging than getting
information on the more restricted constructs; one potential approach would be to use
global positioning system tracking, perhaps through a smart phone, to gather the data.
Ultimately, the authors argue, the benefits of learning about older adults’ routine
activities and examining the role of these activities in health and disease are likely to be
worth the investment that such studies will require.
In Chapter 5, Moen offers a different theoretical approach, institutional theory, for
analyzing the issues surrounding aging. In this context “institutions” are not places
where organized social activities take place, as described by Cagney and colleagues in the
previous chapter, but instead are “taken-for-granted schemas about ‘appropriate’
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behavior—formal and informal rules and conventions representing collectively developed
patterns of living which often reflect organizational and community answers to past
problems and uncertainties.” Or, in other words, institutions are conscious or
unconscious rules about how to behave in and think about various social situations. They
come in various forms: practices and conventions, policies, programs, and so on.
Although institutional theory offers an important prism through which to examine social
arrangements, to date it has been applied only sparingly in the study of aging.
After describing a number of ways in which current research in the sociology of
aging has connections and overlaps with institutional theory, Moen makes several
suggestions for future research directions that combine institutional theory and the life-
course approach with basic concepts and theories from sociology. The first suggestion is
to move beyond the individual as the unit of analysis to look also at “organizational,
occupational, associational, regulatory, family, and governmental policies and
conventions” and how they intersect with individual lives to shape various aspects of the
aging process. Moen’s chapter also underlines the importance of studying social change
both within and across cohorts and doing so in a way that can capture the heterogeneity,
differences in risk, and inequality in cohorts as they age and explain these variations in
institutional terms. Such work could point to interventions and policies that could focus
on the most vulnerable and aim to reduce differences in risk.
THE INTERACTION BETWEEN BIOLOGY AND SOCIAL FACTORS
Some of the most exciting opportunities for new research in the field of aging
involve interdisciplinary collaborations that have the potential to examine research
questions from multiple angles, produce new insights and perspectives on long standing
problems, elicit a new awareness of the value of certain types of data, and allow the
dissemination of science across a wide multidisciplinary audience. The study of the
biological effects of social forces—particularly as it applies to the aging process—is still
in its infancy, and many questions remain. As Gruenewald notes in Chapter 6, the study
of biosocial processes in human aging is primarily the product of work in two areas of
research: social epidemiology and social and health psychology. Over the years social
epidemiologists have accumulated a great deal of data indicating that various social
factors—socioeconomic status (SES), education, social isolation, a lack of social support,
social networks and the social environment—affect rates of morbidity and mortality.
One of the most striking results from such research is the finding that the correlations
between social risk factors and poor health are similar to—and sometimes greater than—
the correlations between biomedical factors, such as smoking or obesity, and poor health.
Recently, social surveys such as the Health and Retirement Study (HRS) and the National
Social Life, Health and Aging Project (NSHAP) have begun collecting biomarkers. This
holds great promise for providing new insights into the potentially important role of
biological influences and their interaction with the social and economic environment.
At the same time that social epidemiologists have been tracing out the effects of
social factors on health with large-scale studies, social and health psychologists have
been investigating the same phenomena on a smaller scale, using measures of social and
biological processes that are finer grained than those used in earlier epidemiological
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research. The work has included examinations of how psychosocial stressors and other
social factors, such as the presence of supportive relationships, affect various biological
measures, such as the level of stress hormones or the expression of various stress-related
genes. New technologies for measuring biomarkers in the field have even made it
possible to observe the biological effects of various social experiences on individuals as
they go about their daily lives.
After describing the background of the field, Gruenewald reviews the major
findings from research on biological processes. There is, for example, a large and
growing body of evidence that connects lower socioeconomic status with a variety of
poor health outcomes: shorter life expectancies and greater mortality rates, increased
chances of contracting most diseases, and diseases that progress more quickly.
Furthermore, it now seems clear that having a lower SES early in life results in increased
health risks later in life in a way that is independent of the effects of socioeconomic status
at that later time. This has led to the development of the accumulation of risk model,
which predicts that various adverse social factors, such as low SES, have negative
biological effects that accumulate over the life course, so that an older adult’s health
prospects are shaped by social experiences from throughout his or her life. As
Gruenewald notes, however, many questions about this phenomenon remain to be
answered, such as exactly when and how the effects of socioeconomic status leave their
biological mark. In concluding the chapter, Gruenewald points to a number of areas in
this field that need further investigation, such as “… a greater understanding of the range
of social conditions linked to biological processes, the characteristics of biosocial
interactions at different phases of the life course, and how such processes operate across
time to influence healthy aging.”
While it is undoubtedly true that by combining biological and social data,
researchers are opening up new fields of inquiry and are able for the first time to explore
many new questions and connections, in Chapter 7 Weinstein and colleagues offer a
somewhat less optimistic view of the value of recent biosocial survey efforts. According
to the authors, biosocial research to date has not fully lived up to initial expectations. The
authors also are particularly critical of certain theoretical concepts such as allostatic load
and argue that there is generally an urgent need for stronger and better theory to be
developed at a similar pace to additional data collection efforts in order to better guide
future investigations.
In developing a deeper understanding of how social forces affect health, it is
necessary to delve into the specifics of exactly what happens inside the human body, on a
cellular and molecular level, in response to social stimuli. One of the most promising
areas of research along these lines examines how social forces affect the rate of gene
transcription. In each cell of the body some genes are active and others are inactive, and
the pattern of activity varies over time, partly in response to external stimuli. An active
gene is one whose DNA is being transcribed into messenger RNA, which is the
molecular that directs the production of proteins—the ultimate product of the genes.
In Chapter 8 Shanahan describes the subfield of social genomics that studies how
social factors affect the regulation of gene transcription—that is, the activity rates of
various genes in a cell. More specifically, he examines what is known about how
socioeconomic status affects the rates of gene transcription in ways that ultimately result
in stress-related inflammatory responses and inflammation-related disease. Shanahan
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suggests that future population studies will need to look at a wide variety of social and
biological processes that take place on different levels over periods of many decades. In
particular, because modeling the effect of social forces on health will require the
inclusion of processes at every level from the cellular to the societal, future studies
should examine variables across these levels—accumulating data on patterns of gene
transcription and on the stress experienced by various socioeconomic groups, for
example, as well as on many of the other variables between these two extremes.
Furthermore, because the effects of social factors on individuals can start
accumulating before the age of five and because diseases develop over many decades, the
most effective studies will follow individuals for much of their lives, gathering social and
biological data at many different points along the life course. Finally, improving our
understanding of social genomics will require both the creation of better measures of
social context and the development of diverse research designs that can strengthen
evidence of causality and also tease out how various contexts—policy settings, political
economies, demographic compositions, and so forth—shape the effects of socioeconomic
status on gene expression. “The payoff for such efforts,” Shanahan writes, “will be
increasingly thorough explanations of SES gradients in health, and thus the scientific
basis for effective prevention and intervention.” Commenting on Shanahan’s paper,
Schnittker raises a number of useful points that are worthy of consideration including
speculation on the possible consequences of fully adopting a social genomic agenda on
the future direction of aging research (Chapter 9).
INTERVENTION TRIALS
Ultimately, if theoretical knowledge about the aging population is to be put to
practical use in improving the health status of people as they age, it will be important to
translate it into sound behavioral health interventions as well as clinical trials. But while
carrying out such intervention trials may at first seem straightforward, there are actually
many challenges to performing such trials in a way that provides useful, trustworthy data.
In Chapter 10 Syme and King begin their discussion of clinical intervention trials with a
review of the 2000 Institute of Medicine report Promoting Health: Intervention
Strategies from Social and Behavioral Research. Although generally optimistic about the
potential of intervention trials based on social and behavioral research, the report noted
that, with few exceptions, most such trials up to that point has either failed or had only
modest success. In large part, Syme and King suggest, this is because of an array of
challenges facing researchers who undertake such trials. The authors argue, for example,
that it is difficult to carry out a true randomized controlled trial because the subjects who
are serving as the control group may decide themselves to make changes in their health-
related behavior, making them less useful as controls. In other cases, the subjects in the
treatment group may change their behavior in ways other than those specified for the
trial, making it difficult to attribute any changes in outcome solely to the treatment.
Selection bias is another concern, as those who are willing to take part in—and to
complete—extensive health-related trials are in some cases likely to be more health-
conscious and to differ in other significant ways from the general population. The
authors conclude that results of intervention trials are quite sensitive to the selection of
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risk factors, the selection of outcomes, and the time frame over which the intervention is
carried out; a poor choice in any of these areas can make it difficult to discern the true
effects on an intervention. Finally, because of the way that many different factors, some
of which may be seemingly insignificant, can affect the outcome of interventions, it can
be difficult to reproduce the results of a study. Researchers may need to be content with
finding general patterns in results rather than demanding strict reproducibility.
Fortunately, the science of intervention has made a number of advances since the
release of the IOM report. There have been a number of advances in the methodology of
randomized controlled trials, for example; some of these advances have increased the
real-world relevance of such trials, while others have focused on the best ways to induce
multiple behavioral changes to take into account the fact that most diseases are
influenced by multiple risk factors. Another advance has been the use of “stealth
interventions” that use subjects’ interests in areas other than their own health—such as
the environment or their faith—to induce them to change health-related behaviors. The
chapter ends with several suggestions for improving clinical intervention trials in the
future.
LOOKING TO THE FUTURE
As the papers in this volume demonstrate, there is great value in applying the
tools of sociological research to the study of aging. While practitioners of the sociology
of aging can certainly point to a great many achievements made to date, many important
questions remain as yet answered. Yet many new and promising techniques and
approaches remain to be applied. The most valuable approaches may be those that tackle
the issues surrounding aging at multiple levels and from various angles simultaneously.
The papers here offer a starting point and a set of arrows pointing in directions
that seem likely to reward further investigation. Certainly one among many promising
recent developments has been the emergence of new and highly innovative data that are
enabling researchers to better understand how genes and social environments work in
concert to vary the course of aging. This area of research is already producing much
interesting work and it seems that its future is particularly promising. Nonetheless, there
are few long-term issues facing this country that are more important than the aging of its
population and the changes that this aging will bring, it is our hope that the volume will
begin conversations, trigger ideas, and instigate research projects that will, in time,
combine to lead to a far deeper and more complete understanding of how individuals,
groups, and society as a whole will be evolving in the face of this historical shift.
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