Social engagement and cognitive decline in older African‐Americans: The Minority Aging Research Study

Abstract

AbstractBackgroundSocial engagement in later life is associated with lower rates of cognitive decline and dementia, but most research has been conducted in primarily White cohorts. Little is known about this relationship in older African Americans, and some promoters of cognitive reserve in Whites may not have the same benefits in African Americans.MethodsWe used data from the Minority Aging Research Study (MARS), a study of community‐dwelling African American older adults in Chicago. Social activity was measured using an 8‐item scale assessing frequency of participation in activities involving social interaction (mean=2.5, SD=0.5). Social network size was assessed as the number of children, family, and friends seen at least once a month (mean=6.4, SD=6.0). Loneliness was measured with a 5‐item Likert scale assessing perceived emotional isolation (mean=2.1, SD=0.6). Life space is a measure of spatial movement through 6 zones of the environment from bedroom (smallest) to out of town (largest) (mean=5.5, SD=0.9). Global cognitive function was the average of z‐scores for 19 standard cognitive tests. Linear mixed models were used to test for associations with level and rate of change in cognitive function, with terms for each social engagement variable at baseline, age at baseline, sex, education, time since baseline, and interactions with time.ResultsParticipants (n=768; mean age=73.5, SD=6.3) were followed for an average of 6.3 years (SD=4.6). Higher social activity was related to slower cognitive decline (est=0.021, SE=0.008, p=0.011), but not to level of cognitive function (est=0.052, SE=0.036, p=0.15). Alternately, loneliness and a larger life space were not related to cognitive decline (est=0.003, SE=0.007, p=0.64; and est=0.001, SE=0.005, p=0.82, respectively), but were related to level of cognitive function (est=‐0.104, SE=0.029, p<0.001; and est=0.062, SE=0.020, p=0.002, respectively). Social network size was not related to level or rate of change in cognition.ConclusionsIn older African Americans, social activity was related to less cognitive decline, while other measures of social engagement were related to level but not rate of change in cognitive function.