PrEP Chicago: A randomized controlled peer change agent intervention to promote the adoption of pre-exposure prophylaxis for HIV prevention among young Black men who have sex with men

Abstract

Background/aims: Advances in biomedical prevention strategies such as pre-exposure prophylaxis (PrEP) represent a new opportunity for reducing HIV incidence among young Black men who have sex with men, for whom the number of new HIV infections continues to rise. However, studies have documented low rates of PrEP uptake in this community. Research suggests that the peer networks of young Black men who have sex with men play important roles in their sexual health decisions. PrEP Chicago is a randomized controlled trial network intervention designed to increase PrEP uptake among young Black men who have sex with men living in Chicago. The aims of this study are twofold. Aim 1 is to estimate the effectiveness of a peer change agent intervention for (1) increasing the number of referrals made to a PrEP information line, (2) increasing the rate of PrEP adoption among non-participant peers, and (3) increasing PrEP knowledge, attitudes, and intentions among participants. Aim 2 is to determine the individual and network variables that explain peer change agent effectiveness.

Methods: PrEP Chicago is a social network intervention that utilizes the influence of peer change agents to link young Black men who have sex with men in Chicago to PrEP. Young Black men who have sex with men were recruited using respondent-driven sampling. Once screened for eligibility, participants were randomly assigned to either one of two treatment sequences: (1) intervention treatment in Year 1 followed by a minimal contact attention control in Year 2 or (2) the minimal contact attention control in Year 1 followed by treatment in Year 2. The treatment consists of a PrEP/peer change agent training workshop followed by booster calls for 12 months. The attention control consists of a sex diary activity designed to help participants assess sexual risk. Psychosocial, sexual health, and network data are collected from all participants at baseline and at 12- and 24-month follow-ups.

Results: In total, 423 participants aged 18-35 have been enrolled (more than 100% target enrollment) and have completed baseline data collection. A majority of participants in both intervention and control groups reported having heard of PrEP before enrolling in the study, yet also reported having had no current or prior experience taking PrEP. Statistical analyses await completion of Year 1 of the trial in March 2018.

Conclusion: PrEP Chicago addresses a gap in HIV prevention research and intervention design by utilizing the existing social networks among young Black men who have sex with men as mechanisms for information diffusion, behavioral influence, social support, and empowerment. Therefore, interventions that leverage peer influence processes to facilitate PrEP uptake are promising strategies to improve sexual health engagement and overcome disparities in outcomes among this at-risk population.

Trial registration: ClinicalTrials.gov NCT02896699.

Keywords: Black men who have sex with men; HIV prevention; intervention design; network intervention; peer change agents; pre-exposure prophylaxis; social networks.

Conflict of interest statement

Declaration of conflicting interests

The Author(s) declare(s) that there is no conflict of interest.

Figures

Figure 1

Study Design. After Year 1, participants switch conditions; participants initially assigned to the control group switch to the intervention group and vice versa. All measures are assessed at baseline, 12 months (corresponding to the end of Year 1 of a participant’s enrollment) and 24-months (corresponding to the end of Year 2) as listed in Table 1. Participants who initially randomize into the intervention group receive the risk assessment training at the 12-month switch over and are no longer boostered by intervention staff. Participants who initially randomize into the attention control receive the PrEP / peer change training at the 12-month switch over and are boostered by intervention staff on a monthly basis as described below. Because of this design, the primary analyses of the effectiveness of the intervention will be comparison between groups of outcomes assessed at the end of Year 1.

Figure 2

YBMSM Facebook friendship network (N=1,144) generated from downloaded Facebook data among YBMSM who participated in UConnect, a longitudinal cohort study of YBMSM in Chicago. The Facebook friendship network is comprised of UConnect respondents (N=400) and their non-respondent Facebook friends (N=744) that are connected to at least 10% of the respondent nodes. Among these nodes are a total of 51,904 Facebook friendship ties. Influential nodes are colored in red and include network members who score highly on betweenness centrality, eigenvector centrality, Key Player, or Bridging metrics. Influential nodes were identified using algorithms in the influenceR package (https://cran.r-project.org/web/packages/influenceR/index.html). The graph visualization was created using the ggnet package in R (https://briatte.github.io/ggnet/).