Never before has the global population included as many older adults as it does today. Over the past century in the United States alone, the proportion of persons aged 65 years or older increased more than threefold, from 4.1% to 12.9%.1 This issue of the Journal devoted to “Healthy Aging” opens a dialogue for examining innovative roles for public health and the health care system in relation to a broad spectrum of priorities involving the aging population. Despite the acknowledged challenges of limited resources and economic uncertainty, as this issue's articles suggest, opportunities abound to improve the health and functioning of older adults and enhance intergenerational programs and policies that enrich all of society. Additional articles for this series will be published in subsequent Journal issues over the coming years.
AN UNPRECEDENTED DEMOGRAPHIC TRANSITION
At least three major factors—the aging of the baby boom generation (those born from 1946 through 1964), the growing numbers of persons living with multiple chronic conditions, and the reform of the US health care system—are prompting animated discussion and debate about aging in the United States. Just last year, the unprecedented demographic transition received national attention as the first group of baby boomers began turning 65 on January 1, 2011. Beyond this explosion in absolute size compounded by increased longevity, the population of older adults is undergoing dynamic growth in terms of racial and ethnic diversity, as well as changes in functional capacity.1 Although an aging population undoubtedly places pressure on policymakers as they seek to stem rising health care costs, insufficient attention has been focused on new approaches designed to improve community-based services, quality of life, and mobility across the life course.2
Given the stark reality that by 2030 an estimated 20% of Americans will be aged 65 years or older,1 several vexing questions present themselves. Is public health prepared to address a rapidly aging population and create a vision for positive change? What does an aging society mean for the health of everyone? How do recent demographic developments challenge traditional views about and roles for older adults? Do conceptual models exist that can be invoked or adapted to enhance understanding of the reasons for the observed variations in the health and functioning of older populations? What innovative approaches might public health practitioners implement to address the major causes of disease and disability and promote quality of life for all populations as they age?
AN UNHERALDED PUBLIC HEALTH PRIORITY
Public health, which has played a key role in bringing about this demographic phenomenon, historically has been defined in relation to populations and has focused its attention on addressing the leading causes of death and identifying risk factors in particular groups. With people living longer, the challenge is to help them stay healthy and maintain a high quality of life at every age, regardless of the onset of chronic conditions. Although this challenge is a monumental one, healthy aging has unfortunately been at the periphery of the public health agenda since public health's origin in the industrialized cities of the 19th century.3 Even during the mid-1960s, when the struggles of older Americans received considerable attention by other sectors, public health was largely a bystander. Recall that the Social Security Amendments of 1965 established the Medicare and Medicaid programs, and the Older Americans Act of 1965 led to the creation of the Administration on Aging. But public health agencies remained outside the purview of aging and were not explicitly mentioned in the Older American Act until 1987, when a provision (the Disease Prevention and Health Promotion Services [OAA Title IID]) mandated that,
In carrying out such program, the Assistant Secretary shall consult with the Directors of the Centers for Disease Control and Prevention and the National Institute on Aging.3
Furthermore, it was not until 1978 that the Gerontological Health Section was established as part of the American Public Health Association.4 In 2010, this section was renamed Aging and Public Health to reflect
the broad scope of interests of our members, and to distinguish ourselves as the organization that uniquely focuses on the intersection of public health and the aging population.5
Belatedly but importantly, in 1994, a major conference on aging finally focused on the needs of older adults and called for cross-agency collaborations and the promotion of health for older adults.6
A FOUNDATION OF UNDERSTANDING
In the late 1990s, a comprehensive study on aging in the United States was used to create an epidemiological model for “successful aging.”7 This model provides a foundation for conceptualizing aging, conveying lessons learned, and opening a dialogue on public health opportunities for addressing aging in society. Although the precise meaning of “successful aging” has been debated over the years, most definitions include three core components: function (maintaining a high level of mental and physical functioning), health status (minimizing the risk of disease and disability), and social inclusion (maintaining an active engagement with life).7
In terms of function, considerable variability exists within the older adult population, from those who may be characterized as functional and independent to those who are considered to be frail and dependent. A significant proportion of older adults have some type of physical limitation in functioning, such as walking two to three blocks.8 In 2007, for example, among adults aged 65 to 74 years, 13.0% of men and 21.8% of women reported at least one such limitation; the proportion was even higher among those aged 85 years or older, with 40.4% of men and 55.9% of women reporting at least one limitation.8 To fully address the potential opportunities and challenges of improving the lives of older adults, the public health community must consider the full spectrum of function within this population.
Another key characteristic of the aging population is the emergence of a high prevalence of multiple (defined as two or more) chronic conditions, including somatic diseases, behavioral health problems, cognitive and other functional limitations, and geriatric syndromes such as falls and frailty. Already, more than one in four Americans are living with multiple, concurrent chronic conditions.9,10 As might be expected, the prevalence of multiple chronic conditions is substantial among older adults, contributing to their frailty and functional limitations, in addition to adding considerably to health care spending.9,10
A PROMISING DIRECTION
Research has documented that community-based programs and policies can successfully improve function and quality of life among older adults through interventions designed to increase physical activity, prevent falls, and improve functioning.11 Even for people aged 85 years or older, mobility and balance can be improved with basic weight training exercises.11 Other relevant, successful approaches include initiatives designed to benefit people of all ages, such as community-based safe walking programs and environmental change policies. Public health can support these promising approaches by creating infrastructure supports that ensure the reach and replication of programs and policies that can benefit the growing numbers of older adults.
The aging services network is also working to help older adults avoid social isolation by designing and testing new ways for them to contribute to society. One example of this approach is a national program called Experience Corps12 that places older volunteers as tutors in underserved elementary schools. The program provides academic support to students and creates new roles for older adults that are cognitively demanding and socially productive. Moreover, evaluation findings from Experience Corps demonstrated improvements in physical health among the adult participants.13
A RESOURCE FOR FUTURE GENERATIONS
The consequences of having a larger, more diverse older population will be dramatic, notably in the economic, housing, and health care sectors, and in the education and training requirements for the health and social services workforces.2,3 As the number of older adults continues to grow, public health professionals will have to find innovative ways to meet the multiple needs of this population, as well as to address the shortage of professionals trained in aging and to help relieve the often overwhelming demands placed on caregivers and family members. The public health system too must contribute its expertise to address the opportunities and challenges brought on by an aging US population. For example, public health surveillance systems that assess and monitor the health of the broader population can help track changes in the life conditions of older adults. Public health training programs can be used to educate professionals about issues related to aging and confront myths associated with growing old.
Opportunities abound for public health to embrace the potential, as well as the needs, presented by the aging of the population. One important next step is to develop competencies in healthy aging for schools of public health. Public health policies and interventions also can be leveraged and expanded through collaborations with the aging services network and other nontraditional partners, including transportation, housing, and planning agencies. Public health preparedness initiatives must explicitly attend to the vulnerabilities of older adults during natural disasters, threats of infectious disease epidemics, and other emergencies. Finally, public health might profit from innovative approaches such as Experience Corps that reframe healthy aging and engage older adults in initiatives that bring value to their lives and to the larger community. The Journal’s series presents a lens for sharpening our collective focus on the aging population as a resource rather than a burden to enrich our society.
This article was prepared for the CDC series on aging and the roles of public health.