Introduction
The mission of the NIA is to improve the health and well being of older Americans through an extensive program of high-quality research. There are currently 35 million Americans over the age of 65 B more than at any other time in history. Of these, more than four million are over 85, and some 65,000 have attained their hundredth birthday. In the coming years, the ranks of American elders are expected to swell; by 2030, the number of individuals age 65 and older likely will double, reaching 70.3 million and comprising a larger proportion of the entire population, rising from 13 to 20 percent.1 In particular, explosive growth is anticipated among those most at risk for disease and disability, people age 85 and older, whose ranks are expected to grow from 4.3 million in 2000 to at least 19.4 million in 2050.
The aging of the population presents a number of social and economic challenges as increasing numbers of Americans reach retirement age. It also has important implications for our nation's health. For example, more than half of all Americans over age 65 show evidence of osteoarthritis in at least one joint. 2 Over half of Americans older than 50 have osteoporosis or low bone mass.3 Cardiovascular disease, cancer, and diabetes remain common among older Americans, and as many as 4.5 million Americans suffer from Alzheimer's disease (AD).4
However, we now know that aging itself is not the cause of disease, disability, and frailty. Rather, disease and disabling processes influenced by age-related changes in the body and by unhealthy choices and sedentary lifestyles are the most important factors in compromising the quality of life for older people. This fundamental shift in thinking was reinforced most recently with insights from the National Long Term Care Survey (NLTCS). According to this study, the rate of disability among older Americans dramatically declined from the 1980s through the mid 1990s, even among people age 85 and older. These findings, along with evidence from a number of other studies, suggest more strongly than ever that disease and disability can be delayed or even prevented through specific interventions.
At the same time, however, this downward trend in disability among the elderly is in real danger of reversal. Data from the National Health Interview Survey have found that, over the same period, the disability rate actually rose significantly for people ages 18–59, with the two most important causes of disability being musculoskeletal problems, particularly back problems, and mental illness. Findings also indicated that combined disability cases from musculoskeletal problems and diabetes, both of which can be associated with obesity, were increasing more rapidly by the mid-1990s than those from other problems, and that the growing prevalence of obesity is the dominant factor in the rise in disability among individuals ages 50–59.5
The NIA portfolio emphasizes research aimed at increasing the Ahealthspan,”or years of healthy, active life expectancy. With guidance from the National Advisory Council on Aging, the NIA conducts and supports research on the biochemical, genetic, and physiological mechanisms of aging in humans and animal models; the structure and function of the aging nervous system; social and behavioral aspects of aging processes and the place of older people in society; and the pathophysiology, diagnosis, treatment, and prevention of age-related diseases, degenerative conditions, and disabilities. In all of its efforts, the Institute pays special attention to reducing health disparities among different groups of Americans. NIA-supported researchers can be found in all fifty states, and the Institute also conducts a thriving program of training opportunities for researchers wishing to become involved in aging research.
- Federal Interagency Forum on Aging Related Statistics. Older Americans 2000: Key Indicators of Well-Being. 2000.
- See “Handout on Health: Osteoarthritis,” National Institute of Arthritis and Musculoskeletal and Skin Diseases, July 2002.
- See America's Bone Health: The State of Osteoporosis and Low Bone Mass in Our Nation. National Osteoporosis Foundation, February 2002.
- Hebert LE et al.: Alzheimer disease in the U.S. population: Prevalence estimates using the 2000 Census. Arch. Neurol. 60: 1119-22, 2003.
- Lakdawalla DN, Bhattacharya J, Goldman DP. Are the Young Becoming More Disabled? Health Affairs 23(1): 168-76, 2004.