Physical Activity and Executive Function in Aging: The MOBILIZE Boston Study

OBJECTIVES To determine the relationship between physical activity and cognition, specifically executive function, and the possible mediating role of factors such as cardiovascular disease (CVD) and CVD risk factors, chronic pain, and depressive symptoms. DESIGN Cross-sectional study. SETTING Population-based study of individuals aged 70 and older in the Boston area. PARTICIPANTS Older community-dwelling adults (n=544; mean age 78, 62% female). MEASUREMENTS Presence of heart disease (self-reported physician diagnosed), pain, and depressive symptomatology were assessed using interviewer-administered questions. Blood pressure was measured. Engagement in physical activity was determined using the Physical Activity Scale for the Elderly (PASE). Cognitive function was measured using a battery of neuropsychological tests. RESULTS The older adults who engaged in more physical activity had significantly better performance on all cognitive tests, except for Letter Fluency and the memory test of delayed recall, after adjusting for age, sex, education, and total number of medications. With further adjustment for CVD and CVD risk factors (heart disease, diabetes mellitus, stroke, and hypertension), pain, and depressive symptoms, PASE score remained significantly associated with executive function tests. CONCLUSION Even after multivariate adjustment, neuropsychological tests that were executive in nature were positively associated with physical activity participation in this cohort of older community-dwelling adults. In contrast, delayed recall of episodic memory was not associated with physical activity, supporting the idea that the relationship with executive function represents a specific biologically determined relationship.