Ratios of different age groups provide useful though crude indicators of potential demands on resources and resource availability. One set of ratios, known variously as dependency or support ratios, compare the age groups who are most likely to be in the labor force with the age groups typically dependent on the productive capacity of those working—the young and the old, or just the old. A commonly used ratio is the number of persons age 15–64 per persons age 65 and older. Even though many in some countries do not enter the labor force until significantly older than age 15, retire before age 65, or work past age 65, the ratios do summarize important facts, especially in countries where financial support for the retired comes partially or mainly from those currently in the labor force through either a formal pension system or through informal support from the family. While many countries still have very basic pension systems with incomplete coverage, in Europe public pensions are quite generous, and these countries face dramatic changes in their ratios of working age to older populations. Over the next 40 years, Western Europe faces a drop in the ratio from 4 to 2. In other words, while in crude terms there are today 4 workers supporting the pensions and other costs of each older person, by 2050 there will only be 2. China faces an even steeper drop from 9 persons of working age to only 3, while Japan declines from 3 to just 1. Even in India, projected to become the most populous country, the decline is quite steep from 13 to 5.
The dramatically declining number of workers per older person (however determined) is at the crux of the economic challenge of population aging. The extra years of life that can be considered the crowning achievement in medicine and public health of the last 150 years have to be financed. The economic model of the life cycle assumes that people are economically productive for a limited number of years and that the proceeds of their work during those years have to be smoothed over to finance consumption during less economically productive ages, either within families or by institutions such as the state in order to provide for the young, the old, and the infirm. There are only so many ways to meet the challenge of an extended period of dependency, including increasing the productivity of those in the labor force, saving more, reducing consumption, increasing the number of years worked by increasing the age of retirement, increasing the voluntary nonmonetary productive contributions of the retired, and immigration of very large numbers of young workers into the “old” countries. Pressures to increase retirement ages in industrialized countries and to reduce benefits are increasing. But no single one of these measures can bear the full load of adaptation to population aging, since the changes would have to be so severe and disruptive as to be politically impossible. More likely, there will be some combination of these measures.
Population health and the ability to function at work and in everyday life interact with these population ratios in significant ways. The physical and cognitive capacity to continue to work at older ages is crucial if the age of retirement is raised. Similarly, caregiving often requires significant physical and emotional stamina. Further, healthier older populations require less caregiving and medical services. Just two decades ago, the prevalent view of aging was highly pessimistic. Epidemiologists held that while modern medicine could keep older people alive, nothing much could be done to prevent, delay, or significantly treat the degenerative chronic diseases of aging. The result would be that more and more older people with chronic diseases would be kept from dying, with the consequent piling up of the older people disabled by chronic disease. Surprisingly, between 1984 and about 2000, the prevalence of disability in the 65+ population in the United States declined by about 25%, suggesting that in this respect, aging was more plastic than had been previously believed (Fig. 93e-4). All the causes of this significant shift in disability are not yet understood, but rising levels of education, improved treatment of cardiovascular diseases and cataracts, greater availability of assistive devices, and less physically demanding occupations have been found to contribute. One calculation showed that if the rate of improvement could be maintained until 2050, that the numbers of disabled in the older population could be kept constant in the United States despite the aging of the baby boomers and the older population itself growing older. Unfortunately, the rapid increase in obesity rates could slow and perhaps even reverse this most positive trend. Because of the absence of comparable data in other countries, it is less certain whether the same pattern of improvement in disability rates (with recent deceleration) is occurring outside of the United States. Using estimates and projections of disease prevalence from the Global Burden of Disease Study, the global population of those “dependent and in need of care” is projected to rise from about 350 million in 2010 to over 600 million in 2050. Worldwide, about half of the older persons in need of care (two-thirds of the dependent population age 90 and above) suffer from dementia or cognitive impairment. A global network of longitudinal studies on aging, health, and retirement is now providing comparable data that may allow more definitive projections on disease and disability trends in the future. One estimate (World Alzheimer’s Report 2010) projected that the 36 million people with dementia worldwide in 2010 would increase to 115 million by 2050. The largest increases would occur in low- and middle-income countries where about two-thirds already live. The estimated costs were $604 billion in 2010 with 70% occurring in North America and Western Europe. A 2013 study using a nationally representative U.S. sample found that annual dementia costs could be as high as $215 billion. Direct costs of dementia care exceeded the direct costs for either heart disease or cancer. Given the age-associated prevalence of dementia and the expected increase in the older population, coupled with the associated decline in family members able to provide care, countries need to plan for a pandemic of individuals requiring long-term care.
Disability prevalence, various years 1982–2005, by age group over 65, United States. (Adapted from KG Manton et al: Proc Natl Acad Sci U S A. 103:18374, 2006.)
Population aging, and related demographic changes including changes in family structure, could affect the “supply side” of long-term care as well as the demand for care and health care. In every country, long-term care of the disabled and the chronically ill relies heavily on informal, typically unpaid caregivers—usually spouses or children; and increasingly in more developed countries, caregivers for the oldest old are in their 60s and early 70s. Although there are many men who provide care, on the population level, informal caregiving is still mainly done by women. Because women live longer than men, lack of a spousal caregiver is especially likely to be a problem for older women. Both men and women have fewer children on whom they can call for informal caregiving, because of the worldwide decline in fertility rates. An increasing proportion of older men in Europe and North America have spent much or all of their adult lives apart from their biological children. Lower fertility rates, delayed marriage, and increasing divorce rates mean that people approaching old age may be less likely to have close ties with daughters and daughters-in-law—the adults who have in the past been the most common caregivers apart from spouses. Adult women who in the past have provided uncompensated care (and much other essential volunteer work) are now more likely than in the past to be working for pay and thus have fewer hours to devote to the unpaid roles.
These broad demographic and economic trends do not dictate particular social adaptations or policy responses, of course. One can imagine many different responses to the challenges of caring for the disabled—increased reliance on home health agencies and assisted living communities, “naturally occurring retirement communities” in which neighbors fulfill many of the roles once reserved for close kin; private or even publicly financed direct payments to compensate formerly unpaid family caregivers (a reform that has proved very popular in Germany). These and other responses to the challenge of long-term care are being tested in aging countries, and continued experimentation will no doubt be needed.