CROI 2017 Abstract e-Book

Abstract eBook

Poster and Themed Discussion Abstracts

Results: 17,406 participants were included in the IPD analysis: 1,987 (11.4%) HIV-infected and 15,419 (88.6%) HIV-uninfected. The greatest proportion of people diagnosed with HIV were stably housed (12.0%), followed by marginally housed (9.8%), and homeless (9.6%). Median age was 30 in stably housed participants and 37 in marginally housed and homeless participants. The majority of individuals, overall, and by study, were male (89.3%), except the all-female WHC+. Compared to those in stable housing, living in marginal housing during the study reference period showed an inverse association with HIV diagnosis (overall OR: 0.63, 95% CI: 0.27-1.43), with the exception of WHC+ (OR: 1.66, 95% CI: 1.07-2.58). Overall, there was no association between homelessness and HIV infection at baseline (overall OR: 0.93, 95% CI: 0.60-1.42). Conclusion: Counter to hypotheses and some extant literature, homelessness was not associated with HIV diagnosis, with individual studies showing associations in both directions. In contrast, recent marginal housing showed an inverse association with HIV diagnosis, which may indicate people in marginal housing are targeted by services that alter their HIV testing patterns. The models were sensitive to the inclusion of international studies, suggesting there may be heterogeneity in definition of marginal housing and homelessness between countries.

Poster and Themed Discussion Abstracts

854 HIV INCIDENCE AND RISK BEHAVIORS IN THE BANGKOK MSM COHORT STUDY, THAILAND, 2006–2015 Timothy H. Holtz 1 , Anchalee Varangrat 2 , Philip Mock 2 , Warunee Thienkrua 2 , Wannee Chonwattana 2 , Wipas Wimonsate 2 , Wichuda Sukwicha 2 , Marcel Curlin 3 , Eileen Dunne 4 , Anupong Chitwarakorn 5 1 CDC, Atlanta, GA, USA, 2 Thailand Ministry of Pub Hlth–US CDC Collab, Nonthaburi, Thailand, 3 Oregon Hlth and Scis Univ, Portland, OR, USA, 4 US CDC, Nonthaburi, Thailand, 5 Thailand Ministry of Pub Hlth, Nonthaburi, Thailand Background: We assessed 10-year HIV incidence trend and risk factors for incident infection among men who have sex with men (MSM), and transgender women (TGW), participating in the Bangkok MSM Cohort Study (BMCS) at the Silom Community Clinic (SCC) in Bangkok from 2006–2015. Methods: MSM and TGW aged >18 years were enrolled into BMCS. Participants provided socio-demographic and sexual risk behavior data by computer-assisted self-interview every 4 months for up to 60 months. HIV testing was performed on oral fluid with serologic confirmation of all reactive specimens and nucleic acid amplification testing (NAAT) of all negative specimens obtained after February 2010. We calculated incidence per 100 Person Years (PY) and cumulative incidence by Kaplan-Meier survival analysis, determining risk factors for incident HIV infection using Cox regression analyses with time-varying covariates. We evaluated trends in HIV incidence per 100 Person Years (PY) by quarter using a restricted cubic spline for time in a Poisson regression. Results: Among 1744 BMCS participants followed from 2006–2015, 1371 tested HIV-negative at baseline, and 1259 (72%) of these participants had follow-up. We detected 271 infections (n = 22 diagnosed by NAAT) in 4798 total person-years, for an overall HIV incidence density of 5.6 PY (95% CI: 5.0–6.4). HIV incidence rose from 1.3 PY in Q2/2006 to a peak of 8.2 PY in Q1/2008, then declined steadily (inverted U-shaped curve) (Figure). Cumulative incidence at 60 months of follow up was 23.6% overall, and varied by age group: 32.5% among 18-21 year olds; 25.0% among 22-29 year olds; and 16.3% among ≥30 year olds (p < 0.001). Multivariable risk factors for HIV incidence were younger age (adjusted Relative Risk [aRR] 2.18) and lack of HIV testing before enrolment (aRR 1.36). Significant covariates reported for the last 4 months of each individual follow-up visit were use of drugs for sexual pleasure (aRR 2.59); inconsistent condom use (aRR 1.73), group sex (aRR 1.60); receptive anal intercourse (aRR 1.57); anti-HSV-2 antibody (aRR 1.51); living alone or with a roommate (vs. with a partner or family) (aRR 1.43); and anti-HSV-1 antibody (aRR 1.39). Conclusion: HIV incidence among MSM and TGW in Bangkok was as high as 8.2 PY. Combination HIV prevention interventions that reduce HIV transmission during receptive anal intercourse without a condom, especially targeting young men with a history of drug use, HSV, or multiple partners, could significantly impact the epidemic.

CROI 2017 369