Abstract 9234: Effects of a 26-Week Randomized, Controlled Exercise Intervention on Arterial Stiffness, Endothelial Function, and Cognition in Adults Atrisk for Alzheimer Disease

Abstract

Introduction: Arterial stiffness progresses with age and is associated with cardiovascular disease (CVD) events and cognitive decline. Alzheimer’s disease (AD) risk factors like physical inactivity overlap significantly with progression of arterial stiffness. Aerobic exercise training reduces arterial stiffness and may bolster cognition at a time of life when the risk of AD heightens. Hypothesis: Following a 26-week aerobic exercise intervention, improvements in cognitive function will be significantly correlated with improvements in carotid artery stiffness and endothelial function. Methods: Late-middle-aged adults with normal cognition and parental history of AD were randomized to a 26-week exercise training intervention designed to increase physical activity (PA) levels (Enhanced PA; n=11) or maintain Usual PA (n=12). At baseline and following the intervention we used ultrasound to measure local stiffness of the right common carotid artery, brachial artery flow mediated dilation, and tested cognitive function. Pre- and post- intervention changes in outcome variables were compared between groups using independent sample t-tests or ANCOVA and results are presented as mean ± standard deviation. The association between pre-post intervention changes in arterial stiffness and cognitive function were assessed using Pearson correlation coefficients. Results: The pre-post intervention changes for Usual PA vs Enhanced PA were not different for carotid artery stiffness (Young’s Elastic Modulus: (219 ± 1088 mmHg vs -131 ± 384, p=0.12) or endothelial function (0.49 ± 1.69 vs 0.47 ± 1.71, p=0.32). Improvements in cognitive function were not significantly correlated with changes in arterial stiffness or endothelial function (r = -.27-.25, p = .24-.81). Conclusions: The findings of this pilot study do not support the hypothesis that improved cognition following exercise would be associated with improved carotid artery stiffness and endothelial function.