Mean arterial pressure, fitness, and executive function in middle age and older adults

Previous literature suggests that higher fitness is related to better executive function in older adulthood, but the mechanisms underlying this association are poorly understood. While many studies have focused on these associations in older adulthood, recent evidence suggests the importance of cardiorespiratory fitness (CRF) and long-term blood pressure control on cognitive functioning. The purpose of the current study was to examine whether mean arterial pressure (MAP) mediated the association between CRF and executive function in middle age and older adults. Participants were adults (age 40+) without any self-reported psychiatric and neurological disorders or cognitive impairment from the Nathan Kline Institute Rockland Sample (N = 224, M age = 56). CRF was defined by V̇O(2max) estimated via a bike test, neuropsychological testing was used to examine executive functioning, and MAP was calculated from systolic and diastolic blood pressure recordings. Mediation models were analyzed controlling for age, sex, and education. Results indicated that higher CRF was associated with better inhibition (B = -0.0048, t = -2.16, p = 0.03) and there was a significant indirect effect of greater CRF on better inhibition through lower MAP (B = -0.0011; CI [-0.0026, -0.0002]). There were additional significant indirect effects of greater CRF and better fluency (B = 0.0028; CI [.0009, 0.0053]) and planning (B = 0.0037; CI [.0014, 0.0074]) through lower MAP. This suggests that MAP may be an underlaying physiological mechanism by which CRF influences executive function in mid- and older adulthood.