Physical Activity and Memory Performance: A Mendelian Randomization Study

Abstract

Background Physical activity has been associated with better memory performance by epidemiological studies. However, the conclusion was still controversial, and whether the association was causal is elusive. Methods To evaluate the role of physical activity in memory performance from a genetic perspective, we first estimated their genetic correlation, and then conducted two-sample and multivariable Mendelian randomization analyses. Results Significant positive genetic correlation was identified between moderate to vigorous physical activity and prospective memory (PM) and episodic memory (EM). Genetically determined higher physical activity was significantly associated with better performance of both PM and EM after the Bonferroni correction. Such association was further verified using summary statistics from another study on overall physical activity. The results were robust under all sensitivity analyses. Conclusions Current results suggested physical activity could improve memory performance. These findings help better understand the role of physical activity in memory, and provide some lifestyle recommendations.