Effects of multi-component non-pharmacological interventions on cognition in participants with mild cognitive impairment: A systematic review and meta-analysis

Background and purpose: Mild cognitive impairment (MCI) describes a stage of intermediate cognitive dysfunction where the risk of conversion to dementia is elevated. Given the absence of effective pharmacological treatments for MCI, increasing numbers of studies are attempting to understand how multicomponent non-pharmacological interventions (MNPI) could benefit MCI. The purpose of this systematic review and meta-analysis were to assess the effects of two-component MNPI (simultaneous cognitive intervention based on cognitive stimulation, cognitive training and/or cognitive rehabilitation or combined cognitive and physical interventions) on global cognition and cognitive functions in older adults with MCI and to compare the degree of efficacy between the two interventions. Methods: After searching electronic databases (PubMed, Web of Science, Scopus and Cochrane Central) for randomized controlled trials and clinical trials published from 2010 to 18 January 2021, 562 studies were found. 8 studies were included in this review, with a fair to good quality according to the PEDro scale. Results: From a random-effects model meta-analysis, the pooled standardized MMSE mean difference between the intervention and control groups showed a significant small-to-medium effect in global cognition in MMSE score (0.249; 95% CI = [0.067, 0.431]), which seemed to be greater for combined physical and cognitive interventions. However, the meta-analyses did not show any effects regarding specific cognitive functions. Conclusion: Our analyses support that MNPI could improve the global cognition in older adults with MCI. However, more studies are needed to analyze the potential benefits of MNPI on older adults with MCI.