Sexually Transmitted Infection Testing and Prevalence Before and After Preexposure Prophylaxis Initiation Among Men Aged ≥18 Years in US Private Settings.

Background: The Centers for Disease Control and Prevention recommends initial and follow-up sexually transmitted infection (STI) and HIV testing when taking HIV preexposure prophylaxis (PrEP). We assessed frequencies of STIs and HIV testing and rates of STIs before and after PrEP initiation among men aged ≥18 years.

Methods: We used the OptumLabs database for this cohort study. We measured STI/HIV testing rates and prevalence in 2 time intervals: (1) within 90 days before and on the date of PrEP initiation and (2) within 45 days of the 180th day after the date of PrEP initiation.

Results: Of 4210 men who initiated PrEP in 2016 to 2017 and continuously used PrEP for ≥180 days, 45.7%, 45.7%, and 56.0% were tested for chlamydia, gonorrhea, and HIV, respectively, at the second time interval. These percentages were significantly lower than those at the first time interval (58.3%, 57.9%, and 73.5%, respectively; P < 0.01). Chlamydia and gonorrhea prevalence rates at the second time interval were 6.5% and 6.2%, respectively, versus 5.0% and 4.7%, respectively, at the first time interval. Most gonorrhea or chlamydia infections at the second time intervals seem to be new infections new infections.

Conclusions: Sexually transmitted infection/HIV testing for PrEP users in the real-world private settings is much lower than in clinical trials. High STI prevalence before and after PrEP initiation in this study suggests that patients taking PrEP have an increased risk of acquiring STI. Interventions to improve provider adherence for PrEP users are urgently needed.