The Clinically Significant Changes in the Composition and Functional Diversity of the Vaginal Microbiome in Women with Type 2 Diabetes Mellitus

Abstract

Type 2 diabetes mellitus (T2DM) significantly influences the composition and diversity of the vaginal microbiome, with implications for mucosal immunity, infection risk, and genitourinary health. This study aimed to investigate the vaginal microbiome profiles in women with T2DM, with a focus on differences according to menopausal status and associations with Candida colonization and the use of sodium–glucose cotransporter 2 (SGLT2) inhibitors. Compared to healthy controls, women with T2DM exhibited a decreased abundance of Lactobacillus species and increased microbial diversity. Community state of type (CST) IV, characterized by low Lactobacillus abundance and dominance of anaerobic taxa, was prevalent in the T2DM group. Among Candida-positive patients, Lactobacillus iners-dominant CST III was frequently observed, along with elevated levels of total and L-lactic acid. SGLT2 inhibitor users exhibited a different CST distribution pattern and slightly lower microbial richness and diversity, although these differences were not statistically significant. These findings underscore the impact of T2DM and its treatment on vaginal microbial composition and highlight the importance of considering vaginal health as part of comprehensive diabetes management in women.