Comparing Men Who Have Sex With Men Only and Men Who Have Sex With Men and Women Visiting a Public Sexually Transmitted Infection Clinic.

Background: Men reporting same-sex behaviors are disproportionately impacted by sexually transmitted infections (STIs). Differences in clinical characteristics and STIs in men who have sex with men only (MSMO), with men and women (MSMW), and with women only (MSW) are not well described.

Methods: First visits to 2 Baltimore City STI clinics 2011-2016 from MSMO and MSMW compared with an age-matched random sample of MSW were analyzed. Acute STI (aSTI) included chlamydia, gonorrhea, nongonococcal urethritis, and primary or secondary syphilis. χ2 Tests and logistic regression examined associations.

Results: Among N = 1226 MSMO, N = 491 MSMW, and N = 1717 MSW, most identified as Black/African American; mean age (29.8 years) was similar across groups. The percentages of MSMW, MSMO, and MSW who reported ≥2 partners in the last 6 months were 73.5%, 67.2%, and 60.3%, respectively. "Always" condom use was reported by 20.4%, 17.4%, and 14.1% of MSMW, MSMO, and MSW. Overall HIV prevalence was 13.8%. Among those tested, urogenital chlamydia prevalence rates were 21.7%, 8.3%, and 3.9% ( P ≤ 0.01) in MSW, MSMW, and MSMO. Urogenital gonorrhea prevalence was 11.6%, 7.7%, and 8.3% in MSMW, MSW, and MSMO, respectively. Extragenital STI (range, 2.7%-21.9%), nongonococcal urethritis (25.2%), and primary or secondary syphilis (5.3%-5.7%) positivity was similar in MSMW and MSMO. Older age was inversely associated with STI diagnosis in MSW and MSMO only; consistent condom use was protective against aSTI in MSW (adjusted odds ratio, 0.60; P < 0.01) and MSMW (adjusted odds ratio, 0.54; P = 0.03) only.

Conclusions: Differences in behaviors and clinical characteristics associated with aSTI suggest that MSMO, MSMW, and MSW have diverse sexual health needs and may require tailored interventions to improve sexual health outcomes.