Effectiveness of Tai Chi on cognitive function among older adults with mild cognitive impairment: a systematic review and meta-analysis of randomized controlled trials

Objective: To evaluate the effectiveness of Tai Chi on cognitive function in older adults with mild cognitive impairment.Methods: A systematic search of eight English and five Chinese electronic databases was conducted to identify randomized controlled trials of Tai Chi as the intervention. The main outcomes included executive function, episodic memory, visuospatial function, working memory, concentration, memory complaints, and global cognition. The Cochrane RoB tool was used to assess bias in the study. Meta-analysis was conducted using Review Manager 5.4. Narrative syntheses were performed if meta-analysis was inappropriate.Results: A total of eleven trials (905 participants) were included. Meta-analysis showed that Tai Chi significantly and moderately affected executive function (SMD = -1.01, 95% CI: -1.54 to -0.47, p < 0.001), episodic memory (SMD = 0.59, 95% CI: 0.24 to 0.94, p = 0.001), visuospatial function (SMD = 0.38, 95% CI: 0.15 to 0.60, p < 0.001), and global cognition (SMD = 0.57, 95% CI: 0.14 to 1.00, p = 0.01).One study showed that Tai Chi could improve verbal fluency.Conclusions: This review reveals that Tai Chi can improve executive function, episodic memory, visuospatial function, and global cognition in older adults with mild cognitive impairment, but not working memory, concentration, or memory complaints. These findings are consist with existing reviews about the effectiveness of Tai Chi. Long-duration (> 1500 min) Tai Chi is more effective for improving global cognition. However, the findings should be interpreted with caution due to the potential risk of bias and limited sample sizes of the included studies. Future trials should examine the effectiveness of standardized Tai Chi intervention on cognitive outcomes in older adults with mild cognitive impairment.