The proportion of Americans who are more than 65 years of age is expected to double during the next few decades, and those who reached the age of 65 years in 1994 can expect to live an additional 17 years. These dramatic increases in the numbers and the life expectancy of older Americans are poorly understood. Many studies have linked survival to physical activity. Benefits attributed to physical activity include beneficial changes in glucose and lipid metabolism. Conversely, inactivity has been associated with poor diet, smoking and other risk factors for cardiovascular disease. Glass and colleagues proposed that the emphasis on physical activity could obscure health benefits from other forms of activity. They studied the contribution to survival of social and other activities undertaken by elderly persons.

They used data from a cohort of 2,812 persons aged 65 and older who lived in institutions and in the community. As part of comprehensive data gathering, subjects were asked about social, productive and fitness activities. Social activities included visits to movie theaters, sports and recreational events, recreational traveling and participation in groups. “Productive” activities were defined to include employment, volunteer work, gardening, shopping and housework. Members of the cohort were interviewed at home on four occasions between 1982 and 1994. Telephone interviews were conducted in six intercurrent years. Deaths in the cohort were monitored by tracking local health records and by regular contacts with participants or their families. Status was known on 99 percent of participants by the end of the study.

During the study, 62 percent of participants died. Social, fitness and productive activities correlated only modestly with one another, suggesting that these are independent areas of activity with possibly unrelated influences on health and survival. For social activity, those in the least active quarter were 20 percent more likely to die than those in the most active quarter. For productive and fitness activities, the comparable figures were 35 and 19 percent. The significant survival benefit conferred by social activity persisted after controlling for other variables related to survival. The effect of social and productive activity was strongest among the least physically active participants.

The authors conclude that social and productive activities lower the risk of mortality in the elderly as much as fitness activities. This effect depends on psychosocial as well as physiologic mechanisms and may benefit even physically inactive persons. As this study concurs with earlier findings of benefit from non-physical activity in the elderly, the authors urge clinicians to encourage social and other activities in elderly patients. Such activities can function as “powerful new interventions” to promote the health and longevity of elderly patients.