Identifying High-Risk Populations for Sexually Transmitted Infections in Chinese Men Who Have Sex With Men: A Cluster Analysis

Background: This study aimed to identify subpopulations of Chinese men who have sex with men (MSM) with distinct sexual behavioral patterns and explore their correlations with sexually transmitted infections (STIs).

Methods: We recruited 892 eligible MSM in Xi'an, China, collecting sociodemographic, sexual behavior, and STI data. Cluster analysis identified distinct sexual behavioral patterns, allowing us to examine STI differences across clusters.

Results: Among the 892 MSM analyzed, 3 clusters were identified. Cluster 1 (n = 157) exhibited high-risk sexual behavioral patterns, including the highest median number of sexual partners (5 vs 1 in cluster 2 vs 3 in cluster 3, P < .001), lowest consistent condom use for insertive anal sex (0% vs 64.12% vs 99.76%, P = .004) and receptive anal sex (9.22% vs 67.71% vs 98.91%, P = .006), highest uncertainty of partners' STIs (77.07% vs 57.89% vs 64.5%, P < .001), all recent partners being casual, longest length of sequential sexual acts (6 vs 5 vs 5, P = .045), and highest rates of gonorrhea (20.38% vs 10.09% vs 14.99%, P = .019) and chlamydia (16.56% vs 8.33% vs 13.21%, P = .045). Cluster 2 (n = 228) showed the lowest engagement in high-risk behaviors and STIs, characterized by the fewest sexual partners, highest certainty of partner's STIs, and all recent partners being regular. Cluster 3 (n = 507) showed moderate levels of high-risk behaviors and STIs, with the highest consistent condom use during anal sex.

Conclusions: This study identified 3 subpopulations of Chinese MSM with distinct sexual behavioral patterns. Targeted public health interventions to the most at-risk subpopulations of MSM are essential for STI prevention.