Cardiorespiratory fitness mitigates brain atrophy and cognitive decline in adults at risk for Alzheimer's disease

Abstract

Abstract Introduction Cardiorespiratory fitness (CRF) may mitigate Alzheimer's disease (AD) progression. This study examined the longitudinal associations of CRF with brain atrophy and cognitive decline in a late‐middle‐aged cohort of adults at risk for AD. Methods One hundred ten cognitively unimpaired adults (66% female, mean age at baseline 64.2 ± 5.7 years) completed a baseline graded treadmill exercise test, two brain magnetic resonance imaging scans (over 4.67 ± 1.17 years), and two to three cognitive assessments (over 3.26 ± 1.02 years). Linear mixed effects models examined the longitudinal associations adjusted for covariates. Results Participants with higher baseline CRF had slower annual decline in total gray matter volume (P = .013) and cognitive function (P = .048), but not hippocampal volume (P = .426). Exploratory analyses suggested these effects may be stronger among apolipoprotein E ε4 carriers. Discussion CRF is a modifiable physiological attribute that may be targeted during the preclinical phase of AD in effort to delay disease progression, perhaps most effectively among those with genetic risk.

Keywords

• aerobic fitness
• apolipoprotein E ε4
• executive function
• exercise
• lifestyle factors
• magnetic resonance imaging