Effects of non-invasive brain stimulation combined with Tai Chi on the physical, cognitive, emotional, sleep, and quality-of-life outcomes in older adults: A systematic review and meta-analysis.

BACKGROUND

Older adults (OAs) experience various dysfunctions, and studies have reported the effects of noninvasive brain stimulation (NIBS) and Tai Chi (TC) on various outcomes in OAs. This review examined the scientific evidence on the effects of NIBS combined with TC (NIBS + TC) on physical, cognitive, emotional, sleep, and quality-of-life (QoL) outcomes in OAs with sleep disturbances or disorders (SDS) and/or mild cognitive impairment (MCI).

METHODS

Databases including Web of Science, PubMed, Physiotherapy Evidence Database (PEDro), Cochrane Library, and Embase were searched. Randomised controlled trials were selected, and their methodological quality and risk of bias were examined using the PEDro scale and Cochrane Risk of Bias evaluation tool, respectively. The data were analysed using both quantitative (meta-analysis) and narrative syntheses. GRADE was used to assess the certainty of evidence.

RESULTS

The meta-analysis showed that active rTMS + TC probably improves sleep efficiency (MD = 1.53%, 95% CI 0.00 to 3.05; I2 = 0%; p (overall) = 0.05; moderate certainty), likely reduces sleep onset latency (MD = -2.71 min, 95% CI -5.79 to 0.36; I2 = 45%; p (overall) = 0.08; moderate certainty), and may reduce mental component of QoL (SF-36 MCS) (MD = -10.55, 95% CI -19.14 to -1.96; I2 = 25%; p (overall) = 0.02; low certainty). Narrative synthesis: rTMS + TC improved sleep quality/cognition (1 study), and sleep disturbances (2). tDCS + TC showed gains in cognition (1) and DT gait (1).

CONCLUSION

In OAs with SDS and/or MCI, Active rTMS + TC probably improves sleep function (moderate certainty of evidence) and shows no superior effects over the control across emotional outcomes (low certainty), with weak preliminary indications for cognitive outcomes. Active tDCS + TC showed weak preliminary indications for DT gait and cognitive outcomes.