Randomized Trial of Exercise and Social Interaction in a Community-Based Sample of Non-Demented Chinese Elders

Overview

A pilot randomized clinical trial was conducted in a random sample of 120 non-demented Chinese elders (ages 60-79) living in a defined community in Shanghai, China to compare the effects of interventions (fast walking, Tai Chi, group intellectual discussion) to no intervention with respect to change in cognition and whole brain volume determined by repeated neuropsychological batteries and MRI scans. Aims included determining the feasibility of recruiting and retaining a random sample of people age 60+ for such a trial as well as collection of preliminary data on the efficacy of the interventions. The long-term goal of this research program is to determine whether sustained physical and/or mental exercise interventions are efficacious in delaying the onset of dementia and to understand the role and mechanisms of brain growth in this process.

Physical exercise has been shown to increase brain volume and improve cognition in randomized trials of non-demented elderly. Although greater social engagement was found to reduce dementia risk in observational studies, randomized trials of social interventions have not been reported. A representative sample of 120 elderly from Shanghai, China was randomized to four groups (Tai Chi, Walking, Social Interaction, No Intervention) for 40 weeks. Two MRI's were obtained, one before the intervention period, the other after. A neuropsychological battery was administered at baseline, 20 weeks and 40 weeks. Comparison of changes in brain volumes in intervention groups with the No Intervention group were assessed by t-tests. Time-intervention group interactions for neuropsychological measures were evaluated with repeated-measures mixed models.