Egocentric Sexual Networks of Men Who Have Sex with Men in the United States: Results from the ARTnet Study

Abstract

In this paper, we present an overview and descriptive results from the first egocentric network study of MSM from across the United States (U.S.): the ARTnet study. ARTnet was designed to support prevention research for human immunodeficiency virus (HIV) and other sexually transmitted infections (STIs) that are transmitted across partnership networks. ARTnet implemented a population-based egocentric network study design that sampled egos from the target population and asked them to report on the number, attributes, and timing of their sexual partnerships. Such data provide the foundation needed for estimating and simulating stochastic network models that are used for disease projection and intervention planning. ARTnet collected data online from 2017 to 2019, with a final sample of 4904 participants who reported on 16198 sexual partnerships. The analytic aims of the study were to characterize the joint distribution of three network parameters needed for modeling: degree distributions, assortative mixing, and partnership length, with heterogeneity by partnership type (main, casual and one-time), demography, and geography. Participants had an average of 1.19 currently active partnerships ("mean degree"), which was higher for casual partnerships (0.74) than main partnerships (0.45). The mean rate of one-time partnership acquisition was 0.16 per week (8.5 partners per year). Main partnerships lasted 272.5 weeks on average, while casual partnerships lasted 133.0 weeks. There was strong but heterogenous assortative mixing by race/ethnicity for all groups. The mean absolute age difference was 9.5 years, with main partners differing by 6.3 years compared to 10.8 years for casual partners. Our analysis suggests that MSM may be at sustained risk for HIV/STI acquisition and transmission through high network degree of sexual partnerships. The ARTnet network study provides a robust and reproducible foundation for understanding the dynamics of HIV/STI epidemiology among U.S. MSM and supporting the implementation science that seeks to address persistent challenges in HIV/STI prevention.

Association Between HIV PrEP Indications and Use in a National Sexual Network Study of Men Who Have Sex with Men

“…The complete methods for ARTnet have been described previously. 14,15 ARTnet is a web-based sexual network study to characterize the sexual partnership networks and engagement in HIV prevention services of MSM in the United States. Eligibility included any lifetime history of male-male sex and age between 15 and 65 years.…”

Projected HIV and Bacterial STI Incidence Following COVID-Related Sexual Distancing and Clinical Service Interruption

“…To fit the network models, we used data from ARTnet, a web-based egocentric network study conducted in 2017–2019 of MSM in the US. 17 Parameters were weighted by census-based race/ethnicity and age distributions to account for ARTnet sampling biases. Multivariate predictors of partnership formation included partnership type, degree distributions by partnership types, heterogeneity in network degree, assortative mixing by race/ethnicity and age, and mixing by sexual position.…”

Modeling an Integrated HIV Prevention and Care Continuum to Achieve the Ending the HIV Epidemic Goals

“…ARTnet was a web-based egocentric network study conducted in 2017-2019 of MSM in the US, with data from 4904 respondents reporting on 16198 partnerships with respect to partnership timing, overlap, and attributes. 19 For this analysis, we included a main effect for geography of residence (city of Atlanta versus all other areas) in model predictions to represent our study target population.…”