Impact of metformin use on neurocognitive functions in older people: a systematic review and meta-analysis

UNLABELLED: Metformin is a widely prescribed drug for managing diabetes mellitus. Recent studies have investigated its potential effects on cognitive function in adults aged 60 years and older, a population that is steadily increasing and often exhibits cognitive impairments associated with aging and other chronic conditions. OBJECTIVE: This study aimed to evaluate the impact of metformin use on cognitive functions in older adults through a meta-analysis. METHODS: A systematic review and meta-analysis were conducted in accordance with the PRISMA guidelines, utilizing the Embase, LILACS, PubMed, Scopus, and Web of Science databases. The review protocol was registered in PROSPERO (CRD42024624045). RESULTS: Thirteen articles met the eligibility criteria for inclusion in this systematic review, of which five provided sufficient data for the meta-analysis. The findings indicate that metformin has a small but positive effect on overall cognitive function in older adults. Additionally, the meta-analysis demonstrated low heterogeneity (49.6%) and a low risk of bias (p>0.05). CONCLUSION: The results suggest that metformin may have a protective effect on the overall cognitive function of older adults, in addition to its well-established metabolic benefits.