High-risk Sexual Behavior for HIV Acquisition is Associated with Gut Microbial Community in Men Who Have Sex with Men.

Background: Gut dysbiosis is observed in men who have sex with men compared with men who have sex with women. However, the association between risk of HIV acquisition and gut microbiota in HIV sero-negative men who have sex with men remains unclear. Methods: We conducted a cross-sectional study in HIV sero-negative men who have sex with men to explore the links between gut microbiota and risk of HIV acquisition. HIV sero-negative men who have sex with men were recruited. Fecal samples were collected for gut microbiota analysis using 16S rRNA gene sequencing. HIV risk assessment tool was used to estimate the risk of HIV acquisition. Latent class analysis was performed to categorize participants into different risk levels. Gut microbiota diversity was analyzed using the R package vegan. Linear discriminant analysis was used to analyze differential taxa between groups. Results: Two independent subgroups were identified. High-risk participants had >2 male partners and mostly engaged in receptive anal intercourse. The high-risk group exhibited significantly higher Shannon index and lower Simpson index, indicating increased gut microbiota diversity. Beta diversity analysis showed significant differences between the high-risk and low-risk groups (F = 2.0245, Conclusions: Risk of HIV acquisition in men who have sex with men is associated with gut dysbiosis, suggesting that gut microbiota may be a potential target for HIV prevention strategies.