1527. Incident Sexually Transmitted Infections among Southern Men Who Have Sex with Men Living with HIV in the Era of Biomedical Prevention

BACKGROUND: Sexually transmitted infections (STI) and HIV disproportionately affect men who have sex with men (MSM) in the U.S. Deep South. The South also continues to bear the majority of incident HIV in the U.S.; concomitantly, STIs have increased among MSM in this region. HIV virologic suppression effectively prevents sexual transmission of HIV (treatment as prevention, TasP), but STIs occur commonly in MSM living with HIV despite this. Here, we describe the incidence of gonorrhea and chlamydia in MSM living with HIV in the context of their viral load (VL) management from 2016 to 2019. METHODS: We analyzed data from adult MSM living with HIV from 2016-2019 in HIV care in Birmingham, AL. Eligible MSM were prospectively enrolled in the CFAR Network of Integrated Clinical Sites (CNICS) and had documentation of at least one HIV viral load and one STI test (gonorrhea or chlamydia at any anatomic site) in the same calendar year. Demographic data is presented by year. STI incident rates were calculated by year by viral load (VL) category, suppressed (VL < 200 copies/ml) and unsuppressed (VL ≥ 200 copies/ml), with incident rate ratios (IRR) and 95% confidence intervals for comparing suppressed VL to unsuppressed VL. RESULTS: The study cohort included 943, 1084, 1080, and 1106 MSM in each year from 2016-2019, respectively. Of these men, 551 (58%), 623 (58%), 639 (63%), and 676 (61%) were Black or African American with a median age (years) of 46, 45, 44, and 43 from 2016-2019. Most had VL < 200 (79%, 81%, 82%, and 80% from 2016-2019). There were 100, 131, 139, and 168 men with positive GC or CT results per year from 2016-2019. The annual incident rates per 100 person years (PY) for MSM by suppressed and unsuppressed VL as well as IRR are presented in Table 1; the IRR ranged from 3.00-4.34 through the study period. Figure 1 shows incidence rate by VL category. [Image: see text] Figure 1. Incidence Rate by Viral Load Category. PY, person years. [Image: see text] CONCLUSION: In this cohort, incident bacterial STIs were common and increased each year in this analysis for both groups, reflecting national STI trends. MSM with suppressed VL had higher bacterial STI incidence rates and higher risk for incident STI compared to MSM with unsuppressed VL. Novel approaches to STI prevention, such as pre- and post-exposure prophylaxis or vaccines, are necessary to alter the STI epidemic in this population and limit its impact on HIV transmission. DISCLOSURES: All Authors: No reported disclosures