The Association between Daily Physical Activity Levels and Brain Atrophy Progression in Middle-aged and Elderly Japanese

Abstract

Brain structural atrophy is associated with impairment in learning function and cognitive function. The purpose of this study was to determine whether daily physical activity prevents age-related brain atrophy progression. The subjects were 381 males and 393 females who had participated in both the baseline and follow-up examinations （mean duration, 8.2 years）．Magnetic resonance imaging of the frontal and temporal lobes was performed at the time of the baseline and follow-up surveys. The number of steps of the subjects was recorded at baseline with uniaxial accelerometry sensors. Multiple logistic regression models were fit to determine the association between number of steps variables and frontal and temporal lobe atrophy progression while controlling for possible confounders. In males, the odds ratio of frontal lobe atrophy progression was increased by 1.480 （95% confidence interval [CI], 1.007-2.175）-fold for every 3,000 decrease in the number of steps. The odds ratio of frontal lobe atrophy progression for the fifth quintile compared to the first quintile in the number of steps was 3.651 （95% CI, 1.304-10.219）．There were no significant differences between frontal lobe atrophy progression and the number of steps in females. There were also no significant differences between temporal lobe atrophy progression and the number of steps in males and females. The results indicate that physical activity is significant predictors of frontal lobe atrophy progression over an 8-year period. Promoting participation in activities may be beneficial for attenuating age-related frontal lobe atrophy and for preventing dementia.