Social resources and cognitive decline in a population of older African Americans and whites

Objective: To examine the relation of social resources and cognitive decline in older adults. Methods: Data are from the Chicago Health and Aging Project, an epidemiologic study of risk factors for Alzheimer disease (AD) and other common conditions in a geographically defined population of older persons. The sample consisted of 6,102 non-Hispanic African Americans (61.2%) and whites, aged greater than or equal to65, who underwent up to three interviews during an average of 5.3 years of follow-up. Each interview included administration of four cognitive function tests from which a composite measure of cognition was formed. Social networks were based on the number of children, relatives, and friends seen at least once a month. Social engagement was measured with four items related to social and productive activity. Results: Higher number of social networks and level of social engagement were positively correlated with initial level of cognitive function ( networks estimate = 0.003, engagement estimate = 0.060, both p < 0.001). Both resources were also associated with a reduced rate of cognitive decline. A high (90th percentile) number of networks reduced the rate of decline by 39% compared to a low level (10th percentile), and high social engagement reduced decline by 91%. These relations remained after controlling for socioeconomic status, cognitive activity, physical activity, depressive symptoms, and chronic medical conditions. Conclusions: Greater social resources, as defined by social networks and social engagement, are associated with reduced cognitive decline in old age.