Longer Term Effects of Diet and Exercise on Neurocognition: 1-Year Follow-up of the ENLIGHTEN Trial.

Abstract

To evaluate the longer term changes in executive functioning among participants with cardiovascular disease (CVD) risk factors and cognitive impairments with no dementia (CIND) randomized to a diet and exercise intervention. A 2 (Exercise) × 2 (Dietary Approaches to Stop Hypertension [DASH] eating plan) factorial randomized clinical trial. Academic tertiary care medical center. Volunteer sample of 160 older sedentary adults with CIND and at least one additional CVD risk factor enrolled in the ENLIGHTEN trial between December 2011 and March 2016. Six months of aerobic exercise (AE), DASH diet counseling, combined AE + DASH, or health education (HE) controls. Neurocognitive battery recommended by the Neuropsychological Working Group for Vascular Cognitive Disorders including measures of executive function, memory, and language/verbal fluency. Secondary outcomes included the Clinical Dementia Rating-Sum of Boxes (CDR-SB), Six-Minute Walk Distance (6MWD), and CVD risk including blood pressure, body weight, and CVD medication burden. Despite discontinuation of lifestyle changes, participants in the exercise groups retained better executive function 1 year post-intervention (P = .041) compared with non-exercise groups, with a similar, albeit weaker, pattern in the DASH groups (P = .054), without variation over time (P's > .867). Participants in the exercise groups also achieved greater sustained improvements in 6MWD compared with non-Exercise participants (P < .001). Participants in the DASH groups exhibited lower CVD risk relative to non-DASH participants (P = .032); no differences in CVD risk were observed for participants in the Exercise groups compared with non-Exercise groups (P = .711). In post hoc analyses, the AE + DASH group had better performance on executive functioning (P < .001) and CDR-SB (P = .011) compared with HE controls. For participants with CIND and CVD risk factors, exercise for 6 months promoted better executive functioning compared with non-exercisers through 1-year post-intervention, although its clinical significance is uncertain. J Am Geriatr Soc 68:559-568, 2020.