# Identifying subgroups of Chinese men who have sex with men based on sexual behavior and drug use patterns using a clustering analysis approach

## TL;DR

This study identifies subgroups of Chinese men who have sex with men based on drug use and sexual behavior patterns, finding that those using drugs for sex have higher risk behaviors and PrEP use.

## Contribution

The study introduces a clustering approach to identify subgroups of Chinese MSM based on sexualized drug use and sexual behavior patterns.

## Key findings

- MSM who used drugs before sex had significantly higher rates of PrEP use and sexual risk behaviors.
- Self-masturbation was a key indicator for subgrouping among MSM not practicing sexualized drug use.
- Cluster analysis revealed three distinct behavioral subgroups with differing sexual and drug use patterns.

## Abstract

Sexualized drug use (SDU) refers to using drugs before and during sex to enhance experiences, increasing high-risk behaviors, such as condomless sex, multiple sexual partners, and participation in group sex, among men who have sex with men (MSM). This study explores how SDU affects sexual behaviors in Chinese MSM.

We collected demographics, sexual acts, drug use, and condom attitudes data among 890 MSM from across China via WeChat ads through community-based organizations from March 23 to April 22, 2022.Cluster analysis using Gower’s distance and hierarchical clustering explored differences in sexual acts among MSM who reported SDU in their last encounter and otherwise.

Cluster analysis categorized participants into three Clusters. Cluster 3 (n = 155) reported 100% SDU in their last sexual encounter (83.87% poppers use), whereas Clusters 1 (n = 581) and 2 (n = 154) reported none. Compared to other Clusters, Cluster 3 had significantly higher PrEP use (34.90% vs. 17.02% vs. 8.00%, p < 0.0001), more sexual acts over the past 12 months (35.80–61.30 vs. 31.30–56.10 and 4.37–21.22, p < 0.001), more regular (3.16 ± 4.37 vs. 2.27 ± 3.52 vs. 2.51 ± 2.53, p = 0.028) and casual partners (4.55 ± 6.55 vs. 2.48 ± 3.21 vs. 2.74 ± 3.66, p < 0.0001), more partners with STIs (8.39% vs. 3.79% vs. 3.90%, p = 0.029), and lower consistent condom use (48.53% vs. 59.41% vs. 72.28%, p < 0.0001). Cluster 1 had moderate frequency in all sexual acts except self-masturbation, which was most common in Cluster 2.

SDU is a stratum for identifying MSM subgroups, and MSM who reported SDU demonstrated higher sexual risk behaviors and PrEP usage. Among those not practicing SDU, self-masturbation is a key behavioral indicator for subgrouping.

The online version contains supplementary material available at 10.1186/s12889-025-22388-x.