In 1963, the U.S. population included 17 million people who were 65 years old or more -- today there are twice as many. Meanwhile, the number of Americans 85 years or older is projected to grow from 3.3 million today to 18.9 million by 2050. Gerontologists say that more research into diseases that afflict older people could help to reduce the number of individuals who require expensive full-time medical care in their later years.

Results from spaceflight life sciences research have demonstrated a number of parallels between the effects of spaceflight and those of aging. These include bone mineral loss and muscle atrophy, changes in cardiovascular regulation, disturbances in the control of balance, disruption of sleep and circadian rhythms, and changes in immune system functioning. As a result, there is interest in the research community about the possibility of using many of the physiological changes induced by spaceflight as models for better understanding processes associated with aging

This research could have benefit back on Earth in two ways. First, by studying what happens to astronauts in space, in those specific areas where there is a parallel, we may learn more about those same changes in the elderly. Secondly, one of NASA's goals is to develop countermeasures to lessen or alleviate the negative effects of spaceflight for the astronauts. It may be that countermeasures developed for the spaceflight changes that also occur in aging, could have therapeutic use or may be helpful to the elderly.

NASA is working jointly with the National Institute on Aging of the National Institutes of Health to better understand the parallelisms between aging and spaceflight. A Memorandum of Understanding between NASA and the NIA was signed in September of 1997. Workshops have been held to foster communication between the gerontological and space life sciences research communities and activities such as joint solicitation and funding of flight and ground-based research are being considered. As a result of the STS-95 mission, NASA scientists and scientists from the NIA intramural research program are working on collaborative research projects.

This is a new and exciting area of research that is just beginning with the STS-95 mission. In some cases its a matter of doing new experiments, in others, it is a matter of taking information we have already learned about spaceflight and applying it to the age related problems. The participation of Sen. John Glenn on STS-95 will provide important preliminary observational data on the interaction between spaceflight and aging. Experiments include studies of the effects of spaceflight on sleep regulation, muscle atrophy, cardiovascular regulation, balance and posture, and immune function. Other types of experiments, to be done on other missions and on the ground, include studies examining the changes in younger crew members and comparing them to older people on Earth, and experiments using appropriate animal and cell culture models.