Effects of probiotic supplementation on cognitive function in elderly: A systematic review and Meta-analysis.

Probiotic supplementation has been linked to changes in cognitive function via the gut-brain axis (GBA). However, the current literature lacks a comprehensive review regarding this matter in the elderly population. Electronic databases including Medline (PubMed), Scopus, Embase, Web of Science, and Google Scholar were comprehensively searched for identifying studies that assessed the effects of probiotics on the cognitive function of the elderly published until July 2020. Articles were critically reviewed and if met the inclusion criteria, entered the study. Among a total of 1374 studies, 10 were eligible for meta-analysis. No significant alteration was found in the cognition of the elderly (SMD=-0.04; 95% CI [- 1.07,0.98]; Our study did not support the hypothesis of the positive effect of probiotics on cognitive function in the elderly population; which might be due to the heterogeneity across the studies.