National Institute on Aging at middle age--its past, present, and future.

The National Institute on Aging (NIA) at the National Institutes of Health (NIH) leads the federal effort conducting and supporting research on aging. It is also designated as the lead within NIH for research on Alzheimer's disease. Since NIA's establishment in 1974, it has grown to a billion dollar enterprise featuring a balanced program of basic, clinical, and behavioral and social science. Investigator-initiated research and strategic investments have been critical to the NIA's success in bringing new insights and understandings to aging processes and diseases and conditions associated with advancing age. In recent years, constraints in the growth of resources have posed new challenges as the NIA and NIH leadership seek to maintain a robust and productive program. This article will review the history of the NIA, discuss current programs and priorities, and point to new directions in research, looking ahead.