Measuring and Increasing HIV Testing among Men Who Have Sex with Men

Abstract

Introduction: HIV testing serves as the entry point into care for HIV-infected individuals and an effective prevention intervention because behavior change and antiretroviral treatment can reduce transmission. Increasing testing among men who have sex with men (MSM) may reduce the burden of HIV infection in this high-risk population. Methods: Data from MSM attending publicly-funded HIV/STI testing programs in King County, Washington, from 2003-2011 were used to evaluate temporal trends in and correlates of HIV intertest intervals (ITI) and reasons for testing. A deterministic, continuous-time model of HIV transmission dynamics was used to estimate the impact of replacing clinic-based tests with home-use tests on population-level prevalence. Results: The median ITIs among MSM seeking HIV testing at the Public Health - Seattle & King County STD Clinic and Gay City Health Project (GCHP) were 215 (IQR: 124-409) and 257 (IQR: 148-503) days, respectively. Over time, ITIs declined at both clinics. In multivariable analyses, younger age, having only male partners, reporting ≥10 male partners in the last year, inhaled nitrite use, history of STI, having a regular healthcare provider, and "regular testing" were associated with shorter ITIs (p<0.05). When asked reasons for testing, 49% of MSM attending GCHP reported it was time for their regular test, 27% reported unprotected sex, 12% reported sex with an HIV-infected partner, 21% reported sex with someone new, 24% were starting a relationship, 21% sought STI/hepatitis screening, 2% suspected primary HIV infection, and 16% reported other reasons. Based on observed levels of clinic-based testing, our model predicted an equilibrium HIV prevalence of 18.6% for Seattle MSM. If all men replaced clinic-based tests with home-use tests, prevalence increased to 27.4% assuming no changes in testing frequency. Regardless of how much more often MSM tested at home, any replacement of clinic-based testing with home-use tests increased prevalence. Conclusions: Efforts are needed to increase frequent, regular HIV testing among MSM to increase opportunities for early identification of HIV infection and linkage to care. Home-use tests may reach HIV-infected persons who would not otherwise test. However, our model suggests that replacing clinic-based testing with home-use tests may increase HIV prevalence among Seattle MSM.