Metformin use lowers risk of neurodegenerative diseases in diabetes patients

China: Findings from a recent meta-analysis showed that metformin use, especially long-term use is tied to a lower risk of neurodegenerative disease (ND) in diabetes patients. However, the researchers add, "owing to a substantial heterogeneity among studies, there is a need for high-quality randomized controlled trials to confirm the finding."

There has always been a controversy on the association between metformin use and neurodegenerative disease onset. To clarify the same, Zubing Mei, Anorectal Disease Institute of Shuguang Hospital, Shanghai, China, and colleagues aimed to determine the relationship between metformin use and ND risk based on data from population-based cohort studies in a systematic review and meta-analysis published in the journal Diabetic Medicine. 

For this purpose, the researchers systematically searched articles in PubMed, EMBASE, and Cochrane Library databases. Using a random-effects model, pooled relative risks (RRs) were obtained. In order to identify the sources of heterogeneity and strengthen the results, subgroup analyses, sensitivity analyses, and meta-regression were performed.  

Twelve population-based cohort studies consisting of 194,792 participants (94,462 metformin users and 100,330 metformin non-users) were eligible to be included in the meta-analysis.