Global prevalence of metabolic syndrome among individuals with bipolar disorder: A systematic review and meta-analysis

Background

Metabolic syndrome is a widespread disease in the general population. The purpose of this study is to investigate the global prevalence of metabolic syndrome in the community of people with bipolar disorder through a systematic review and meta-analysis.

Methods

In this study, we conducted a systematic review and meta-analysis using electronic databases, including PubMed, Scopus, Web of Science, Embase, ScienceDirect, and the Google Scholar search engine. The search was performed using the keywords “metabolic syndrome,” “prevalence,” “meta-analysis,” “bipolar disorder,” “prevalence of metabolic syndrome,” “factors affecting metabolic syndrome. We searched for studies until October 2024 and transferred them to the information management software (EndNote). After excluding duplicated studies, we rigorously evaluated the remaining ones based on the inclusion and exclusion criteria in 3 stages (screening, eligibility, and quality assessment).

Results

In the review of 56 studies with a sample size of 780,099 people, the I² heterogeneity test showed high heterogeneity (I²: 99.3), and based on this, the random effects method was used to analyze the results. Therefore, based on the meta-analysis, the global prevalence of metabolic syndrome was reported at 32.7 (95 % CI: 25.9–40.2) in bipolar patients.

Conclusion

In studying the influential factors, it was found that as the sample size increases, the global prevalence of metabolic syndrome among bipolar patients decreases. Conversely, as the publication year of studies increases, the global prevalence of metabolic syndrome in this population tends to rise. It is important to note that factors such as medication, lifestyle, environment, and genetics directly impact this disease.