Increased Risk of Sexually Transmitted Infections in Men Who Have Sex With Men Taking Preexposure Prophylaxis: A Meta-analysis

Background Men who have sex with men (MSM) are a priority population for preexposure prophylaxis (PrEP) for HIV prevention. We summarized the surveillance data from the studies of MSM taking PrEP versus before taking PrEP to investigate the possible increased risk of sexually transmitted infections (STIs). Methods Two researchers independently searched 5 databases from January 2012 to April 2022 to identify relevant studies reporting the incidence density of syphilis, gonorrhea, and chlamydia infection. Subgroup analyses based on the type and location of research were conducted. The publication bias was detected by Egger's publication bias plot. Results Twenty studies met the inclusion criteria for the meta-analysis. The pooled estimate of incidence density of syphilis was 9.53 per 100 person-years (PY), whereas 36.48 per 100 PY for chlamydial infection and 34.79 per 100 PY for gonorrhea, higher than the MSM before taking PrEP. The results of the subgroup analysis showed that the incidence density tended to be lower in prospective studies than in retrospective studies and lower in North American studies than in other regions' studies. Conclusions The high incidence of STIs in the MSM taking PrEP needs to be increasingly appreciated, and more effective prevention method for STIs is valuable among MSM alongside HIV prevention uptake.