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As a nation, we are in the midst of a demographic shift unprecedented in history. There are currently 35 million Americans over the age of 65 – more than at any other time in history. Of these, over 4 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; between now and 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, up from 13 percent today to 20 percent in 20301. Of great interest is the explosive growth anticipated among those most at risk of disease and disability, people age 85 and older: Their 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 joint2. Over half of Americans over age 50 have osteoporosis or low bone mass3. 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 clinical trials and studies, suggest more strongly than ever that disease and disability can be delayed or even prevented through specific interventions. The challenge now is to maintain and even accelerate the trend in declining disability and to reduce rates of disease amid a steep rise in the number and proportion of older people.

The mission of the NIA is to improve the health and well being of older Americans through an extensive program of high-quality research. The NIA’s portfolio is vast and emphasizes research aimed at increasing the “healthspan,”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 an active program of training opportunities for researchers wishing to become involved in aging research.

  1. Federal Interagency Forum on Aging Related Statistics. Older Americans 2000: Key Indicators of Well-Being. 2000.
  2. See “Handout on Health: Osteoarthritis,” National Institute of Arthritis and Musculoskeletal and Skin Diseases, July 2002.
  3. See America’s Bone Health: The State of Osteoporosis and Low Bone Mass in Our Nation. National Osteoporosis Foundation, February 2002.
  4. Hebert LE, Scherr PA, Bienias JL, Bennett DA, and Evans DA: Alzheimer disease in the US population: prevalence estimates using the 2000 Census. Arch Neurol 60: 1119-22, 2003.