Domain-Specific Physical Activity and Dementia Risk

Higher levels of physical activity were associated with lower risks of all-cause dementia, Alzheimer’s disease, and vascular dementia, but the associations differed substantially by physical activity domain. In this systematic review and meta-analysis, 74 cohort and case–control studies involving 4,227,297 participants were analyzed, with a median follow-up of 10.0 years. Compared with lower levels of activity, higher physical activity was associated with reduced risks of all-cause dementia (RR 0.80), Alzheimer’s disease (RR 0.79), and vascular dementia (RR 0.71). However, these associations varied by domain: leisure-time physical activity (RR 0.76) and household activity (RR 0.85) were associated with lower all-cause dementia risk, whereas occupational (RR 1.20) and commuting physical activity (RR 1.10) were associated with higher risk. Dose–response analyses showed nonlinear inverse associations for leisure-time and occupational activity, although the certainty of evidence ranged from very low to low across domains. These findings suggest that the relationship between physical activity and dementia risk may depend on the activity domain, highlighting the importance of equitable access to safe spaces for exercise, sufficient leisure time, and strategies to mitigate potential risks associated with occupational physical activity. Source: https://www.thelancet.com/