摘要：Objectives. To inform public health efforts to promote independent functioning among older adults, we have provided new national estimates of late-life disability that explicitly recognize behavioral adaptations. Methods. We analyzed the 2011 National Health and Aging Trends Study, a study of Medicare enrollees aged 65 years and older (n = 8077). For 7 mobility and self-care activities we identified 5 hierarchical stages—fully able, successful accommodation with devices, activity reduction, difficulty despite accommodations, and receipt of help—and explored disparities and associations with quality of life measures. Results. Among older adults, 31% were fully able to complete self-care and mobility activities. The remaining groups successfully accommodated with devices (25%), reduced their activities (6%), reported difficulty despite accommodations (18%), or received help (21%). With successive stages, physical and cognitive capacity decreased and symptoms and multimorbidity increased. Successful accommodation was associated with maintaining participation in valued activities and high well-being, but substantial disparities by race, ethnicity, and income existed. Conclusions. Increased public health attention to behavioral adaptations to functional change can promote independence for older adults and may enhance quality of life. An unprecedented number of adults in the United States will reach late life over the next few decades. The US Census Bureau projects that by 2030 the number of older Americans will exceed 70 million (20% of the population), 1 and the vast majority of these individuals will be living with multiple chronic conditions. 2 The risks of disability increase markedly with age and chronic illness, which in turn has consequences for older adults’ quality of life. 3 Although late-life disability prevalence declined over the past quarter century, recent studies suggest such improvements have paused and may reverse course as the baby boom generation enters old age. 4–6 Significantly higher rates among disadvantaged groups also remain a concern. 7 Consequently, late-life disability remains a prominent public health matter 8 and maintaining the ability of older adults to function independently in the community an important goal. 9 Self-care and mobility activities—although not the only targets of functional preservation—have long been recognized as essential to older adults’ well-being and to their continued social and community participation and thus are of particular interest. Public health professionals play a unique role in addressing late-life disability by setting and monitoring population-level goals, designing needs assessments for communities, developing programs and policies to maximize functioning, providing information to older adults and their caregivers, and focusing on gaps for high-risk groups (e.g., minority, low-income populations). 10 With respect to public health monitoring, for example, Healthy People 2020 has targeted a 10% reduction nationally (from a baseline level of 29%) in the proportion of older adults with moderate to severe limitations in daily functioning. The Federal Interagency Forum on Aging Statistics and the Centers for Disease and Control and Prevention also track late-life disability (the latter at the state level), and community needs assessments to promote aging preparedness have included such measures (at the local level). 11–13 Specific measurement approaches vary. Healthy People 2020, for instance, tracks the proportion of older adults who report having difficulty by themselves and without special equipment performing basic activities of daily living (bathing or showering, dressing, eating, getting in or out of bed or chairs, walking, or using the toilet). The Centers for Disease and Control and Prevention tracks those who either are limited in their activities or use special equipment because of a health problem. Other programs focus on needing help from another person with daily activities. A common feature of these monitoring efforts is that they do not permit distinctions according to how older adults carry out daily activities. For instance, the approaches do not allow identification of individuals who have successfully accommodated difficulties by using aids such as walkers and grab bars, which older adults are increasingly adopting to foster independent functioning. 14,15 They also miss altogether individuals who adjust their behavior without recognizing difficulty, for instance by dressing or walking less often (so-called preclinical disability 16,17 ), an at-risk group for whom intervention may delay or deter the need for hands-on care. Hence, current efforts overlook valuable opportunities for assessing public health needs and evaluating program impacts related to independent functioning. To better address the extent to which public health efforts can improve the lives of older adults, a fuller spectrum of functional assessment is needed. Using a new national survey of Medicare beneficiaries, we have introduced a 5-category hierarchy of late-life mobility and self-care limitations. We have identified those who are fully able; have successfully accommodated declines by using assistive technology or environmental features; have reduced their activity frequency but report no difficulty; report difficulty doing activities by themselves, even when using any accommodations they have in place; and receive assistance from another person. We demonstrate how underlying physical and cognitive capacity and reports of multimorbidity vary by each successive category and provide estimates of disparities for key demographic groups. Finally, recognizing the importance of integrating measures of participation and quality of life into studies of disability, 18 we examine connections of the new hierarchy we have developed to 2 such indicators: participation restrictions and subjective well-being. We focus our discussion on the implications of our findings for public health practice and for tracking population-level care needs.
