Association of chemsex and risk of chlamydia, gonorrhoea, and syphilis infections: a systematic review and meta-analysis.

OBJECTIVES

Chemsex, the use of psychoactive substances to enhance sexual experiences, is increasingly recognized as a public health concern, particularly among men who have sex with men (MSM). This behavior is associated with risky sexual practices, including condomless sex, multiple partners, and prolonged sexual sessions, which may elevate the risk of sexually transmitted infections (STIs) such as chlamydia, gonorrhea, and syphilis. This systematic review and meta-analysis aim to quantify the association between chemsex and these bacterial STIs.

STUDY

DESIGN

Systematic review and meta-analysis.

METHODS

A systematic search of PubMed, Embase, and Web of Science was conducted to identify studies reporting associations between chemsex and chlamydia, gonorrhea, or syphilis until November 10, 2024. Eligible studies included observational designs with chemsex participants and STI outcomes. Random-effects meta-analyses were performed to estimate pooled odds ratios (ORs) with 95 % confidence intervals (CIs). Statistical analysis was performed by using R software version 4.4.

RESULTS

A total of 13 studies were included across multiple countries. The meta-analysis revealed a significant association between chemsex and syphilis (pooled OR: 1.741, 95 % CI: 1.337-2.267), gonorrhea (pooled OR: 1.784, 95 % CI: 1.428-2.228), and chlamydia (pooled OR: 1.429, 95 % CI: 1.195-1.710). Two studies reporting hazard ratios for gonorrhea (pooled HR: 1.699, 95 % CI: 1.361-2.121) and chlamydia (pooled HR: 1.202, 95 % CI: 0.972-1.487) showed consistent findings. Heterogeneity across studies was minimal for most outcomes (I2 = 0 %), and prediction intervals supported stable effect sizes.

CONCLUSION

This study confirms that chemsex is significantly associated with an increased risk of bacterial STIs, particularly syphilis and gonorrhea. The findings highlight the urgent need for interventions addressing chemsex behaviors, including harm reduction strategies, STI prevention programs, and culturally competent healthcare services. Future research should focus on standardizing definitions of chemsex, expanding investigations to low- and middle-income countries, and addressing publication bias to ensure global relevance and reliability of evidence.