Effect of physical activity intervention on cognitive function in China: A cluster randomized trial

Current randomized trial evidence on the effect of physical activity (PA) intervention on cognitive function is scarce and mainly found in well-educated populations, limiting its generalizability. Furthermore, the modification effect of education levels remains understudied. We conducted a cluster randomized trial to evaluate the effects of PA intervention on cognitive function in a general older population, and whether education modifies such effects.Eight villages were randomized to the intervention (four villages, n = 240) or the control (four villages, n = 271). The intervention group received an 8-week multilevel PA intervention based on a socio-ecological model, while the control did not. The intervention has been condensed to three levels with activities occurring at the individual (telephone counseling, printed material, and training sessions), interpersonal (peer group), and community levels (group sharing and coaching). The primary outcome was changes in global cognition (overall cognitive function) measured by the Telephone Interview for Cognitive Status (TICS-10) at 12-month follow-up. Repeated measurements were modeled using the linear mixed model, which assumed that the missing values were missing at random.The mean age was 70.94 years (standard deviation 5.71) and 55.6% were women. Compared to the control, the orientation improved from baseline at 12-month follow-up (0.24 points [95% confidence interval (CI), 0.03 to 0.46 points; P = 0.03]). Stratified analysis showed that the global cognition and orientation improved at 12-month follow-up among illiterate participants in the intervention (for global cognition, mean difference, 0.57 points [95% CI, 0.03 to 1.10], P = 0.04; for orientation, mean difference, 0.31 points [95% CI, 0.04 to 0.58], P = 0.03).These results confirm the improvements in orientation in older adults, as well as in global cognition and orientation in the illiterate at 12-month follow-up.