Statin use moderates the beneficial effects of aerobic exercise on older adults' performances on the Stroop test: A subanalysis

Aerobic training can lead to improved cognition in older adults and this effect can be explained by enhanced cardiorespiratory fitness. However, statins could limit the physical benefits of aerobic training by altering the mechanisms through which exercise improves cognition. Whether statins could have an effect on the cognitive benefits associated with aerobic training remains to be elucidated. The objective of this study was to determine whether the cognitive benefits of aerobic training were comparable in statin users and non-users. A total of 144 sedentary participants (60 y.o.; 106 non-users, 38 statin users) were included. Participants were either part of an aerobic training group (n = 75) or a control group (n = 69). Cognition was assessed using the Stroop test. Analyses were performed on z-score changes from pre to post-intervention of Stroop reaction time (RT) and number of errors, using Two-factor ANCOVAs, while controlling for potential confounding factors (age, education, BMI, Charlson Comorbidity Index, sex, protocol and handgrip strength). The moderating effect of statins on the cognitive changes associated with aerobic training was determined through moderation analyses. An interaction effect on the Stroop switching condition was detected between intervention and statin intake (F [1, 140] = 5.659, P 0.01). The intervention effect on switching RT was moderated by statin intake, where intervention improved switching RT only in non-users (Effect = 0.1678; P 0.01). Statins could limit the cognitive benefits of aerobic training on switching capacities in some patients. Future randomized studies including a larger number of participants and looking at different types of statins should be conducted to confirm these results.