Effects of virtual reality combined cognitive and physical interventions on cognitive function in older adults with mild cognitive impairment: A systematic review and meta-analysis

Objective: Combined cognitive and physical interventions based on virtual reality may help delay the progression of MCI to dementia or prevent dementia. However, their efficacy is less well studied compared to pharmaceutical treatments. The purpose of this review was to evaluate the effects of cognitive and physical interventions based on virtual reality on cognitive function (global cognition, memory or executive function/attention) of older adults with mild cognitive impairment. Methods: We searched the PubMed, Web of Science, Scopus, Embase, Cochrane Library, PsycINFO, CINAHL and IEEE from inception to 13 May 2021. Only randomized controlled trials which incorporated virtual reality cognitive and physical components targeted to individuals with mild cognitive impairment were eligible. Two researchers independently conducted document retrieval, study selection, data extraction, and methodological quality evaluation. Result: 7 randomized controlled trials were included in a total of 8 articles. No studies were rated as having a "high" risk of overall bias. The results of a meta-analysis showed that VR combined cognitive and physical interventions enhanced the global cognitive (MD = 2.66, 95% CI = 1.79-3.54, P = 0.03, I 2 = 68%) abilities of older adults with mild cognitive impairment. The meta-analysis indicated that after virtual reality combined cognitive and physical interventions, effects on memory (SMD = 0.03, 95% CI = 0.60 to 0.55, P = 0.78, I 2 = 0%) and executive function/attention (SMD = 0.19, 95% CI = 0.74 to 0.36, P = 0.09, I 2 = 53%) were not statistically significant. Conclusions: The present meta-analysis verifies the potential rehabilitative effects of virtual reality combined cognitive and physical interventions for older adults with mild cognitive impairment. More research is also needed to determine the optimal intensity and timing of interventions in the future.