Initial Trends in Self-Reported Pre-exposure Prophylaxis (PrEP) Use Among Men Who Have Sex With Men With Early Syphilis in California's Syphilis Surveillance System

Abstract

Background. HIV-negative men who have sex with men (MSM) with incident syphilis are at high risk of acquiring HIV and therefore are appropriate candidates for pre-exposure prophylaxis (PrEP), but uptake in California by this population has not been characterized. Methods. This was a cross-sectional analysis of interview data for early syphilis (ES) cases in the California Project Area (CPA, excludes Los Angeles and San Francisco) entered into the California Reportable Disease Information Exchange. Data collection on PrEP use began in February 2015. Self-reported PrEP use was assessed among HIV-negative MSM from April 2015 to March 2016 and stratified by age, race/ethnicity, condom use, HIV status of sex partner, number of sex partners in the past 12 months, and Internet use to meet partners. Results. Between April 2015 and March 2016, there were 5172 early syphilis cases reported in the CPA; 3339 (64.6%) were interviewed. Of interviewed cases, 1973 (59.1%) were MSM. Among those, HIV status was reported for 1811: HIV-positive n = 925 (51%), HIV-negative n = 886 (49%). Of the 669 HIV-negative MSM who responded to the PrEP use question, 119 (17.8%) reported PrEP use, from a baseline of 15.8% in April-June 2015 to 21.9% in January-March 2016. Among HIV-negative MSM ES cases, 24.5% of MSM ages >=45 reported PrEP use, followed by 24.1% of MSM ages 35-44, 22.0% of ages 30-34, 15.3% of ages 25-29, and 8.8% of ages =1 HIV-positive partner versus only negative partners/partners of unsure HIV status (p < 0.0001), higher numbers of sex partners (p < 0.0001), and Internet use to meet sex partners (p = 0.003). Conclusion. Initial trends in CPA surveillance data suggest that PrEP use may be increasing among HIV-negative MSM ES cases; however PrEP coverage may be more limited among those at very high risk of HIV acquisition. These findings highlight opportunities for public health action to educate, promote, and improve access to PrEP for populations at risk.