Network dynamics of HIV risk and prevention in a population-based cohort of young Black men who have sex with men

A Network Science Approach to Sex-Polydrug Use Among Black Sexually Minoritized Men and Transgender Women: The N2 Cohort Study

Black sexually minoritized men (SMM) and transgender women (TW) are subgroups with lower rates of substance use and comparable rates of condom use relative to White SMM and TW yet experience heightened vulnerability to HIV. This study sought to explore associations of substance use, including sex-drug use (i.e., drug or alcohol use during sex to enhance sex), and condomless sex among Black SMM and TW. Data were collected from Black SMM and TW living in Chicago, Illinois, enrolled in the Neighborhoods and Networks (N2) cohort study, from November 2018 to April 2019. We used bivariate analyses followed by a multilevel egocentric network analysis to identify factors associated with condomless sex. We conducted Spearman correlation coefficients to examine correlations between pairs of sex-drugs to enhance sex. We used a bipartite network analysis to identify correlates of sex-drug use and condomless sex. A total of 352 Black SMM and TW (egos) provided information about 933 sexual partners (alters). Of respondents, 45% reported condomless sex and 61% reported sex-drug use. In unadjusted analyses, marijuana (34%) and cocaine/crack (5%) sex-drug use were associated with condomless sex (p < 0.05). Condomless sex was positively associated with sex-polydrug use, or the use of 2+ drugs or 1 drug and alcohol (OR = 1.48; 95% CI: 1.02-2.14; p = 0.039), and negatively associated with sharing an HIV-negative serostatus with a sexual partner (OR = 0.57; 95% CI: 0.33-0.98; p = 0.041), having a different HIV serostatus with a sexual partner (OR = 0.37; 95% CI: 0.21-0.64; p < 0.001) or not knowing the HIV serostatus of a sexual partner (OR = 0.47; 95% CI: 0.26-0.84; p = 0.011). The following pairs of sex-polydrug use had Spearman correlation coefficients higher than 0.3: marijuana and alcohol, ecstasy and alcohol, cocaine/crack and ecstasy, and methamphetamine and poppers (p < 0.05). HIV prevention interventions for Black SMM and TW designed to reduce HIV transmission through egocentric sexual networks could address sex-drug use through sex-positive and pleasure-centered harm reduction strategies and provide and promote biomedical prevention and care options at supraoptimal levels.

Leveraging social networks for identification of people with HIV who are virally unsuppressed

OBJECTIVES

This study investigates primary peer-referral engagement (PRE) strategies to assess which strategy results in engaging higher numbers of people with HIV (PWH) who are virally unsuppressed.

DESIGN

We develop a modeling study that simulates an HIV epidemic (transmission, disease progression, and viral evolution) over 6 years using an agent-based model followed by simulating PRE strategies. We investigate two PRE strategies where referrals are based on social network strategies (SNS) or sexual partner contact tracing (SPCT).

METHODS

We parameterize, calibrate, and validate our study using data from Chicago on Black sexual minority men to assess these strategies for a population with high incidence and prevalence of HIV. For each strategy, we calculate the number of PWH recruited who are undiagnosed or out-of-care (OoC) and the number of direct or indirect transmissions.

RESULTS

SNS and SPCT identified 256.5 [95% confidence interval (CI) 234-279] and 15 (95% CI 7-27) PWH, respectively. Of these, SNS identified 159 (95% CI 142-177) PWH OoC and 32 (95% CI 21-43) PWH undiagnosed compared with 9 (95% CI 3-18) and 2 (95% CI 0-5) for SPCT. SNS identified 15.5 (95% CI 6-25) and 7.5 (95% CI 2-11) indirect and direct transmission pairs, whereas SPCT identified 6 (95% CI 0-8) and 5 (95% CI 0-8), respectively.

CONCLUSION

With no testing constraints, SNS is the more effective strategy to identify undiagnosed and OoC PWH. Neither strategy is successful at identifying sufficient indirect or direct transmission pairs to investigate transmission networks.

Impact of post-incarceration care engagement interventions on HIV transmission among young Black men who have sex with men and their sexual partners: an agent-based network modeling study

Background

Understanding the impact of incarceration on HIV transmission among Black men who have sex with men is important given their disproportionate representation among people experiencing incarceration and the potential impact of incarceration on social and sexual networks, employment, housing, and medical care. We developed an agent-based network model (ABNM) of 10,000 agents representing young Black men who have sex with men in the city of Chicago to examine the impact of varying degrees of post-incarceration care disruption and care engagement interventions following release from jail on HIV incidence.

Methods

Exponential random graph models were used to model network formation and dissolution dynamics, and network dynamics and HIV care continuum engagement were varied according to incarceration status. Hypothetical interventions to improve post-release engagement in HIV care for individuals with incarceration (e.g., enhanced case management, linkage to housing and employment services) were compared to a control scenario with no change in HIV care engagement after release.

Finding

HIV incidence at 10 years was 4.98 [95% simulation interval (SI): 4.87, 5.09 per 100 person-years (py)] in the model population overall; 5.58 (95% SI 5.38, 5.76 per 100 py) among those with history of incarceration, and 12.86 (95% SI 11.89, 13.73 per 100 py) among partners of agents recently released from incarceration. Sustained post-release HIV care for agents with HIV and experiencing recent incarceration resulted in a 46% reduction in HIV incidence among post-incarceration partners [incidence rate (IR) per 100 py = 5.72 (95% SI 5.19, 6.27) vs. 10.61 (95% SI 10.09, 11.24); incidence rate ratio (IRR) = 0.54; (95% SI 0.48, 0.60)] and a 19% reduction in HIV incidence in the population overall [(IR per 100 py = 3.89 (95% SI 3.81-3.99) vs. 4.83 (95% SI 4.73, 4.92); IRR = 0.81 (95% SI 0.78, 0.83)] compared to a scenario with no change in HIV care engagement from pre-to post-release.

Interpretation

Developing effective and scalable interventions to increase HIV care engagement among individuals experiencing recent incarceration and their sexual partners is needed to reduce HIV transmission among Black men who have sex with men.

Funding

This work was supported by the following grants from the National Institutes of Health: R01DA039934; P20 GM 130414; P30 AI 042853; P30MH058107; T32 DA 043469; U2C DA050098 and the California HIV/AIDS Research Program: OS17-LA-003; H21PC3466.

Improving web-based respondent-driven sampling performance among men who have sex with men in the Netherlands

Respondent-driven sampling (RDS) uses the social network of participants to sample people of populations that can be challenging to engage. While in this context RDS offers improvements on standard sampling methods, it does not always generate a sufficiently large sample. In this study we aimed to identify preferences of men who have sex with men (MSM) in the Netherlands regarding surveys and recruitment to studies with the subsequent goal of improving the performance of web-based RDS in MSM. A questionnaire about preferences with respect to various aspects of an web-based RDS study was circulated among participants of the Amsterdam Cohort Studies, a study among MSM. The duration of a survey and the type and amount of participation reward were explored. Participants were also asked about their preferences regarding invitation and recruitment methods. We used multi-level and rank-ordered logistic regression to analyze the data and identify the preferences. The majority of the 98 participants were older than 45 years (59.2%), were born in the Netherlands (84.7%), and had a university degree (77.6%). Participants did not have a preference regarding the type of participation reward, but they preferred to spend less time on a survey and to get a higher monetary reward. Sending a personal email was the preferred option to getting invited or inviting someone to a study, while using Facebook messenger was the least preferred option. There are differences between age groups: monetary rewards were less important to older participants (45+) and younger participants (18-34) more often preferred SMS/WhatsApp to recruit others. When designing a web-based RDS study for MSM, it is important to balance the duration of the survey and the monetary reward. If the study takes more of a participants time, it might be beneficial to provide a higher incentive. To optimize expected participation, the recruitment method should be selected based on the targeted population group.

Social networks, high-risk anal HPV and coinfection with HIV in young sexual minority men

OBJECTIVES

Young sexual minority men (SMM) exhibit a high prevalence and incidence of high-risk genotypes of human papillomavirus (hrHPV) anal infections and a confluence of a high prevalence of HIV and rectal STIs. Social determinants of health (SDOHs) are linked to social network contexts that generate and maintain racial disparities in HIV and STIs. A network perspective was provided to advance our knowledge of drivers of genotype-specific hrHPV infection and coinfection with HIV. The study also examined whether socially connected men are infected with the same high-risk HPV genotypes and, if so, whether this tendency is conditioned on coinfection with HIV.

METHODS

Our sample included 136 young SMM of predominantly black race and their network members of other races and ethnicities, aged 18-29 years, who resided in Houston, Texas, USA. These participants were recruited during 2014-2016 at the baseline recruitment period by network-based peer referral, where anal exfoliated cells and named social and sexual partners were collected. Exponential random graph models were estimated to assess similarity in genotype-specific hrHPV anal infection in social connections and coinfection with HIV in consideration of the effects of similarity in sociodemographic, sexual behavioural characteristics, SDOHs and syphilis infection.

RESULTS

Pairs of men socially connected to each other tend to be infected with the same hrHPV genotypes of HPV-16, HPV-45 and HPV-51 or HPV-16 and/or HPV-18. The tendency of social connections between pairs of men who were infected with either HPV-16 or HPV-18 were conditioned on HIV infection.

CONCLUSIONS

Networked patterns of hrHPV infection could be amenable to network-based HPV prevention interventions that engage young SMM of predominantly racial minority groups who are out of HIV care and vulnerable to high-risk HPV acquisition.

Social Media Communication and Network Correlates of HIV Infection and Transmission Risks Among Black Sexual Minority Men: Cross-sectional Digital Epidemiology Study

BACKGROUND

In the United States, HIV disproportionately affects Black cisgender sexual minority men (BSMM). Although epidemiological and behavioral surveillance are integral to identifying BSMM at risk of HIV infection and transmission, overreliance on self-reported data, inability to observe social contexts, and neglect of populations with limited engagement in health care systems limits their effectiveness. Digital epidemiological approaches drawing on social media data offer an opportunity to overcome these limitations by passively observing in organic settings activities, beliefs, behaviors, and moods that indicate health risks but are otherwise challenging to capture.

OBJECTIVE

The primary aim of this study was to determine whether features of Facebook communication and networks were associated with biological, behavioral, and psychological indicators of HIV infection and transmission risk.

METHODS

Facebook and survey data were collected from BSMM aged 18 to 35 years living in Chicago (N=310). Participants' Facebook posts were characterized using 4 culturally tailored topic dictionaries related to aspects of HIV protection and risk among BSMM (sexual health; substance use; sex behavior; and ballroom culture, a salient subculture in lesbian, gay, bisexual, transgender, and queer communities of color). Social network methods were used to capture structural features of BSMM's Facebook friendships (centrality, brokerage, and local clustering) and Facebook group affiliations. Multivariable regressions revealed relationships between these Facebook features and 5 ground truth indicators of HIV infection and transmission risk (sexually transmitted infection incidence, condomless sex, sex drug use, biomedical prevention, and depression).

RESULTS

Although analysis of participants' Facebook posts revealed that HIV-related topics occupied a small portion of the total messages posted by each participant, significant associations were found between the following HIV risk indicators and Facebook features: Condomless sex, including communication about sexual health (odds ratio [OR] 1.58, 95% CI 1.09-2.29), ballroom culture (OR 0.76, 95% CI 0.63-0.93), and friendship centrality (OR 0.69, 95% CI 0.52-0.92); Sex drug use, including communication about substance use (OR 1.81, 95% CI 1.17-2.79) and friendship centrality (OR 0.73, 95% CI 0.55-0.96) and brokerage (OR 0.71, 95% CI 0.51-0.99); Biomedical prevention, including communication about ballroom culture (OR 0.06, 95% CI 0.01-0.71); and Depression, including communication about sexual health (β=-0.72, 95% CI -1.42 to -0.02), ballroom culture (β=.80, 95% CI 0.27-1.34), friendship centrality (β=-0.90, 95% CI -1.60 to -0.21), and Facebook group affiliations (β=.84, 95% CI 0.25-1.43). Facebook features provided no significant explanatory value for sexually transmitted infection incidence.

CONCLUSIONS

Finding innovative strategies to detect BSMM at risk of contracting or transmitting HIV is critical to eliminating HIV disparities in this community. The findings suggest that social media data enable passive observance of social and communicative contexts that would otherwise go undetected using traditional HIV surveillance methods. As such, social media data are promising complements to more traditional data sources.

Causal Relationships between Personal Networks and Health: A Comparison of Three Modeling Strategies

Prior research documents associations between personal network characteristics and health, but establishing causation has been a long-standing research priority. To evaluate approaches to causal inference in egocentric network data, this article uses three waves from the University of California Berkeley Social Networks Study (N = 1,159) to investigate connections between nine network variables and two global health outcomes. We compare three modeling strategies: cross-sectional ordinary least squares regression, regression with lagged dependent variables (LDVs), and hybrid fixed and random effects models. Results suggest that cross-sectional and LDV models may overestimate the causal effects of networks on health because hybrid models show that network-health associations operate primarily between individuals, as opposed to network changes causing within-individual changes in health. These findings demonstrate uses of panel data that may advance scholarship on networks and health and suggest that causal effects of network support on health may be more limited than previously thought.

Daily Marijuana Use Predicts HIV Seroconversion Among Black Men Who Have Sex with Men and Transgender Women in Atlanta, GA

We evaluated whether different types of substance use predicted HIV seroconversion among a cohort of 449 Black men who have sex with men (MSM) and transgender women (TGW). A community-based sample was recruited in Atlanta, GA between December 2012 and November 2014. Participants completed a survey and were tested for STIs (Chlamydia and gonorrhoeae using urine samples and rectal swabs) at baseline. HIV testing was conducted at 12-months post enrollment. Multivariable binary logistic regression was used to estimate adjusted odds ratios (aORs) and 95% confidence intervals (CI) for associations between substance use and HIV seroconversion. By 12-month follow-up, 5.3% (n = 24) of participants seroconverted. In multivariable analyses, daily marijuana use was positively associated with HIV seroconversion (aOR 3.07, 95% CI 1.11-8.48, P = 0.030). HIV incidence was high and daily marijuana use was associated with a more than threefold increased odds of HIV seroconversion among a community-based cohort of Black MSM and TGW.

Integrated molecular and affiliation network analysis: Core-periphery social clustering is associated with HIV transmission patterns

This study investigates the two-mode core-periphery structures of venue affiliation networks of younger Black men who have sex with men (YBMSM). We examined the association between these structures and HIV phylogenetic clusters, defined as members who share highly similar HIV strains that are regarded as a proxy for sexual affiliation networks. Using data from 114 YBMSM who are living with HIV in two large U.S. cities, we found that HIV phylogenetic clustering patterns were associated with social clustering patterns whose members share affiliation with core venues that overlap with those of YBMSM. Distinct HIV transmission patterns were found in each city, a finding that can help to inform tailored venue-based and network intervention strategies.

Sexual Mixing and HIV Transmission Potential Among Greek Men Who have Sex with Men: Results from SOPHOCLES

HIV incidence among men who have sex with men (MSM) in Greece remains unchanged despite effective response to a recent outbreak among people who inject drugs (PWID). Network factors are increasingly understood to drive transmission in epidemics. The primary objective of the study was to characterize MSM in Greece, their sexual behaviors, and sexual network mixing patterns. We investigated the relationship between serostatus, sexual behaviors, and self-reported sex networks in a sample of MSM in Athens, Greece, generated using respondent driven sampling. We estimated mixing coefficients (r) based on survey-generated egonets. Additionally, multiple logistic regression was used to estimate adjusted odds ratios (AOR) and to assess relationships between serostatus, sexual behaviors, and sociodemographic indicators. A sample of 1,520 MSM participants included study respondents (n = 308) and their network members (n = 1,212). Mixing based on serostatus (r = 0.12, σ_r = 0.09–0.15) and condomless sex (r = 0.11, σ_r = 0.07–0.14) was random. However, mixing based on sex-drug use was highly assortative (r = 0.37, σ_r = 0.32–0.42). This study represents the first analysis of Greek MSM sexual networks. Our findings highlight protective behavior in two distinct network typologies. The first typology mixed assortatively based on serostatus and sex-drug use and was less likely to engage in condomless sex. The second typology mixed randomly based on condomless sex but was less likely to engage in sex-drug use. These findings support the potential benefit of HIV prevention program scale-up for this population including but not limited to PrEP.

Networks Among Racial and Ethnic Minority Men Who Have Sex With Men in HIV Research in the United States: A Concept Analysis

In the past 10 years, research has proliferated investigating the effects of sexual and social networks on the transmission of HIV, especially among racial/ethnic minority men who have sex with men (MSM). This research, however, has been inconsistent in its application of social network theory leading to variations in the measurement of networks and a lack of clarity in the interpretation of results from studies of network data. Efforts to delineate how networks are defined, measured, and interpreted are needed to advance the science of HIV prevention and promote health equity. The aims of this article are to review the literature around networks among racial/ethnic minority MSM, use concept analysis methods to clarify the definition and scope of the concept of networks, and to develop a network typology that can be used to guide measurement and interpretation of networks for HIV research with racial/ethnic minority MSM.

The Role of Networks in Racial Disparities in HIV Incidence Among Men Who Have Sex with Men in the United States

Network factors have been proposed as potential drivers of racial disparities in HIV among Black and Latino men who have sex with men (MSM). This review aimed to synthesize the extant literature on networks and racial disparities in HIV among MSM and identify potential directions for future research. We searched databases for peer-reviewed articles published between January 1, 2008 and July 1, 2018. Articles were included if the sample was comprised primarily of racial/ethnic minority MSM and measured one or more network characteristics. (n = 25). HIV prevalence in networks, social support, and structural barriers were linked to disparities in HIV for Black MSM. Future research should focus on intervention development around social support and other strategies for risk reduction within networks. Given the contribution of structural factors to racial/ethnic HIV disparities, network-level interventions should be paired with policies that improve access to housing, jobs, and education for MSM.

Social-Environmental Resilience, PrEP Uptake, and Viral Suppression among Young Black Men Who Have Sex with Men and Young Black Transgender Women: the Neighborhoods and Networks (N2) Study in Chicago

Young black men who have sex with men (YBMSM) and young black transgender women (TGW) have experienced a stark disparity in HIV prevention and care. Resilience, collective resources to adapt stressors or adversities, may improve HIV prevention and care outcomes. The present study investigated the association of resilience-based factors with PrEP uptake and viral suppression from a socioecological perspective among YBMSM and young black TGW. Data were from the baseline cycle of the Neighborhoods and Networks (N2) Study, an ongoing cohort study of 16-34-year-old YBMSM and young black TGW in Chicago (n = 324). Confidant network-level and neighborhood affiliation variables were created to measure the social-environmental context of resilience. All analyses were stratified by participants' HIV status (184 HIV-negative participants and 140 HIV-positive participants). Among HIV-negative participants, having a parental figure within an individual's confidant network was significantly associated with a greater likelihood of PrEP use. Among HIV-positive participants, confidant network members' awareness of an individual's HIV status was associated with viral suppression. Social support resources from confidant networks could improve HIV prevention and care engagement among YBMSM and young black TGW. Understanding the social and environmental contexts of resilience resource is critical for HIV prevention and care engagement.

Comparison of effectiveness and cost for different HIV screening strategies implemented at large urban medical centre in the United States

INTRODUCTION

Incident HIV infections persist in the United States (U.S.) among marginalized populations. Targeted and cost-efficient testing strategies can help in reaching HIV elimination. This analysis compares the effectiveness and cost of three HIV testing strategies in a high HIV burden area in the U.S. in identifying new HIV infections.

METHODS

We performed a cost analysis comparing three HIV testing strategies in Chicago: (1) routine screening (RS) in an inpatient and outpatient setting, (2) modified partner services (MPS) among networks of the recently HIV infected and diagnosed, and (3) a respondent drive sampling (RDS)-based social network (SN) approach targeting young African-American men who have sex with men. All occurred at the same academic medical centre during the following times: routine testing, 2011 to 2016; MPS, 2013 to 2016; SN: 2013 to 2014. Costs were in 2016 dollars and included personnel, HIV testing, training, materials, overhead. Outcomes included cost per test, HIV-positive test and new diagnosis. Sensitivity analyses were performed to assess the impact of population demographics.

RESULTS

The RS programme completed 57,308 HIV tests resulting in 360 (0.6%) HIV-positive tests and 165 new HIV diagnoses (0.28%). The MPS completed 146 HIV tests, resulting in 79 (54%) HIV-positive tests and eight new HIV diagnoses (5%). The SN strategy completed 508 HIV tests, resulting in 210 (41%) HIV-positive tests and 37 new HIV diagnoses (7.2%). Labour accounted for the majority of costs in all strategies. The estimated cost per new HIV diagnosis was $16,773 for the RS programme, $61,418 for the MPS programme and $15,683 for the SN testing programme. These costs were reduced for the RS and MPS strategies in sensitivity analyses limiting testing efficacy to the highest prevalence patient populations ($2,841 and $33,233 respectively).

CONCLUSIONS

The SN strategy yielded the highest proportion of new diagnoses, followed closely by the MPS programme. Both the SN strategy and RS programme were comparable in the cost per new diagnosis. A simultaneous approach that consists of RS in combination with SN testing may be most effective for identifying new HIV infections in settings with heterogeneous epidemics with both high rates of HIV prevalence and HIV testing.

Socio-Structural and Neighborhood Predictors of Incident Criminal Justice Involvement in a Population-Based Cohort of Young Black MSM and Transgender Women

Black men who have sex with men (MSM) and transgender women are disproportionately affected by criminal justice involvement (CJI) and HIV. This study recruited 618 young Black MSM and transgender women in Chicago, IL, using respondent-driven sampling between 2013 and 2014. Random effects logistic regression evaluated predictors of incident CJI over 18 months of follow-up. Controlling for respondent age, gender and sexual identity, spirituality (aOR 0.56, 95% CI 0.33-0.96), and presence of a mother figure (aOR 0.41, 95% CI 0.19-0.89) were protective against CJI. Economic hardship (financial or residential instability vs. neither aOR 2.23, 95% CI 1.10-4.51), two or more past episodes of CJI vs. none (aOR 2.66, 95% CI 1.40-5.66), and substance use (marijuana use vs. none aOR 2.79, 95% CI 1.23-6.34; other drug use vs. none aOR 4.49, 95% CI 1.66-12.16) were associated with CJI during follow-up. Research to identify and leverage resilience factors that can buffer the effects of socioeconomic marginalization may increase the effectiveness of interventions to address the socio-structural factors that increase the risk for CJI among Black MSM and transgender women. Given the intersection of incarceration, HIV and other STIs, and socio-structural stressors, criminal justice settings are important venues for interventions to reduce health inequities in these populations.

The potential of online social networking data for augmenting the study of high-risk personal networks among young men who have sex with men at-risk for HIV

Capturing dynamics in high-risk personal networks is essential for preventing HIV transmission. Online social networking data offer incentive to augment traditional selfreported approaches for network enumeration. To explore what online networks reveal about dynamics among high-risk associates, we examine the relationship between egocentric confidant and sex networks and personal Facebook friendship networks of a cohort of young Black men who have sex with men. Although overlap exists between self-reported and Facebook associates, the stabilities of each were unrelated. Confidants who were also Facebook friends with a respondent were, however, more likely to be retained. Thus, Facebook networks contain stable confidants.

Collective Avoidance of Social and Health Venues and HIV Racial Inequities: Network Modeling of Venue Avoidance on Venue Affiliation, Social Networks, and HIV Risk

Many younger Black men who have sex with men (YBMSM) are exposed to homonegativity, societal stigma, and racial discrimination in their social environment. This study uses a social network modeling methodology to identify aspects of the social environment that are not often described, that is, the places and spaces or "venues" where YBMSM socialize or where they receive HIV prevention services. In particular, we identify the structural features of avoidance of these venues as an indicator of negative experiences, using bipartite exponential random graph models. Our study theorizes that YBMSM avoid certain venues en masse through information diffusion among social network members. We specify two social mechanisms of collective venue avoidance-(1) homophily (i.e., ego-alter similarity in venue avoidance) and (2) popular opinion leaders (as early adopters)-and test the corresponding hypotheses that (Hypothesis 1) socially connected individuals avoid venues together and that (Hypothesis 2) popular individuals would be more likely to avoid venues. Based on data collected from YBMSM aged 16 to 29 years between 2014 and 2016 in Houston, Texas (N = 227) and Chicago, Illinois (N = 241), results indicate that Hypothesis 1 was supported in both cities but that Hypothesis 2 was supported only in Chicago. The findings suggest that the structural patterns of venue avoidance are different between cities and may inform dissemination of prevention messages and delivery of venue- and social influence-based HIV interventions.

Developing targeted HIV risk predictors for young black men who have sex with men: a two-city comparative study

HIV burden in the United States is geographically and demographically heterogeneous. While efforts over the last few decades have reduced HIV incidence, young black men who have sex with men (YBMSM) account for a significant portion of new HIV diagnoses compared to any other race and age group. The Centers for Disease Control and Prevention has allocated funding to help reduce HIV in the YBMSM community; however, their recommended screening/treatment criteria do not emphasize demographic specificity. To better guide more applicable screening guidelines specifically for YBMSM, we examine demographic, behavioral, sexual network, and biological predictors of HIV status among YBMSM in two demographically distinct cities with high HIV burden in the United States: Chicago, IL and Los Angeles, CA. We perform multivariable logistic regressions to identify predictors of HIV in these populations. We found that having a history of syphilis was the only statistically significant predictor across both cities despite inclusion of other characteristics previously shown to be associated with HIV among YBMSM. Syphilis history could be a powerful HIV risk indicator for YBMSM and, therefore, should be integrated into clinical screening practices for critical biomedical prevention options like HIV pre-exposure prophylaxis.

Social Networks Moderate the Syndemic Effect of Psychosocial and Structural Factors on HIV Risk Among Young Black Transgender Women and Men who have Sex with Men

The interaction between the cumulative effect of psychosocial and structural factors (i.e. syndemic effect) and social networks among young Black transgender women and men who have sex with men (YBTM) remains understudied. A representative cohort of 16-29 year-old YBTM (n = 618) was assessed for syndemic factors [i.e. substance use; community violence; depression; poverty; justice system involvement (JSI)], social network characteristics, condomless anal sex (CAS), group sex (GS), and HIV-infection. The syndemic index significantly increased the odds of CAS, GS, and HIV-infection, and these effects were moderated by network characteristics. Network JSI buffered the effect on CAS, romantic network members buffered the effect on GS, and network age and proportion of family network members buffered the effect on HIV-infection. The proportion of friend network members augmented the effect on GS and HIV-infection. Future research to prevent HIV among YBTM should consider social network approaches that target both structural and psychosocial syndemic factors.

The multiplex social environments of young Black men who have sex with men: How online and offline social structures impact HIV prevention and sex behavior engagement

In the United States, young Black men who have sex with men (YBMSM) remain disproportionately affected by HIV. The social networks in which YBMSM are embedded are generally understood to be critical factors in understanding their vulnerability. In this study, we acknowledge the relational richness of YBMSMs' social environments (what we define as multiplexity) and their increasing prioritization of online social networking sites (SNS). Specifically, we investigate whether protective and/or risky features of YBMSMs' Facebook friendships and group affiliations are related to their HIV prevention and sex behavior engagement, while also accounting for features of their offline confidant (or support) and sex networks. Using data from a population-based cohort study of YBMSM living in Chicago (N=268), we perform a series of multiple logistic regression analyses to examine associations between features of YBMSMs' Facebook, confidant, and sexual networks with three prevention outcomes and three sex behavior outcomes, while also controlling for factors at the individual and structural levels. Results show that network features play a more significant role in predicting engagement in sex behaviors than prevention behaviors. Specifically, having more confidants, having confidants who are family members, meeting sex partners online, having more YBMSM Facebook friends, belonging to Facebook groups with an LGBTQ focus, and having greater subject diversity in one's Facebook group affiliations were significantly associated with one or more sex behavior outcomes. We conclude with a discussion of the implications of our findings for HIV prevention intervention efforts.

Pre-exposure Prophylaxis (PrEP) Awareness and Use Within High HIV Transmission Networks

Improved implementation of pre-exposure prophylaxis (PrEP) should be a valuable tool within communities experiencing high HIV incidence, such as black men who have sex with men (MSM). Using baseline data from the Chicago arm of the Transmission Reduction Intervention Project (TRIP), we examined awareness and use of PrEP within HIV potential transmission networks. Transmission Reduction Intervention Project recruited participants ages 18-69 (N = 218) during 2014-2016 from networks originating from recently and chronically HIV-infected MSM and transgender persons. In total, 53.2% of participants had heard of PrEP, while 8 (6.5%) HIV-negative participants reported ever using PrEP. In multivariable regression, PrEP awareness was associated with identifying as gay, attending some college or higher, having an HIV test in the previous 6 months, and experiencing HIV-related social support. PrEP awareness was not associated with experiencing or observing HIV-related stigma. PrEP use was associated with participants knowing two or more other PrEP-users. These findings demonstrate moderate awareness, but low uptake of PrEP within HIV potential transmission networks in Chicago. Future research should explore how to increase PrEP use in these networks and investigate the social dynamics behind our finding that PrEP users are more likely to know other PrEP users.

The Social Context of HIV Prevention and Care among Black Men Who Have Sex with Men in Three U.S. Cities: The Neighborhoods and Networks (N2) Cohort Study

Background: In many parts of the world, stark racial disparities in human immunodeficiency virus (HIV) prevalence, incidence, prevention, and care outcomes persist among gay, bisexual, and other men who have sex with men (MSM), with Black MSM significantly impacted in the United States (U.S.). Individual-level characteristics, including sexual behaviors and socioeconomic status, do not fully account for racial/ethnic disparities in HIV among MSM. We hypothesize that neighborhood contexts and network characteristics influence risk for HIV infection as well as HIV-related prevention and care behaviors. As such, the study design includes the use of real-time geospatial methods and in-depth assessments of multiple network typologies to investigate the impact of neighborhood and network-level factors on HIV prevention and treatment among Black MSM residing in longstanding priority HIV elimination areas in the U.S., namely Chicago, Illinois and in the Deep South (Jackson, Mississippi and New Orleans, Louisiana) (n = 450, n = 50, and n = 100, respectively). We describe the design, sampling methods, data collection, data management methods, and preliminary findings of the ongoing 'Neighborhoods and Networks (N2) Cohort Study'. Methods/Design: N2 employs a prospective longitudinal design. The sample includes Black MSM participants in Chicago recruited via respondent-driven sampling and assessed every six months over two years of follow-up. Participants enrolled in Jackson and New Orleans are being recruited through existing health and community services and assessed every six months over one year of follow-up. Mobility within and between neighborhoods is being assessed using global positioning system (GPS) technology. Social and sexual networks among Black MSM are being studied through egocentric network inventories as well as newer methods of creating meso-level networks that involve social media (Facebook) and mobile phone contacts. Key HIV prevention outcomes such as pre-exposure prophylaxis (PrEP) care engagement, and HIV/STI (sexually transmitted infections) biomarkers will be examined at baseline and follow-up. Results: As of 31 December 2018, a total of 361 men were enrolled across all study sites: 259 in Chicago and 102 in the Deep South (75 in New Orleans and 27 in Jackson). At baseline, participants ranged in age from 17 to 65 years old (mean = 34.3, standard deviation = 5.1) with 123 men (34.1%) self-reported as HIV positive. While HIV treatment levels were similar between sites, men in the Deep South reported higher rates of adherence than men in Chicago (63.3% versus 49.4%, p = 0.03). Sexual risk profiles were mainly the same between men from different study sites, with 22.9% of men in Chicago and 28.9% in the Deep South reporting consistent condom use during vaginal and anal sex (p = 0.26). Regarding their home neighborhoods, men in the Deep South were more likely than those in Chicago to characterize theirs as having a good reputation (43.1% versus 24.7%, p < 0.001) and as being safe (37.3% versus 21.2%, p = 0.002). Conclusions: The focus on Black MSM in the N2 Study will allow for a nuanced exploration of the attitudes, beliefs, behaviors, and practices of a diverse group of Black MSM. The study is also positioned to provide novel insight about neighborhood and network characteristics that influence HIV-related behaviors. A health equity framework ensures that Black MSM are not explicitly or implicitly deemed as deviant, disordered, or the non-reference group. Findings from N2 will provide guidance for the implementation of more impactful HIV prevention interventions that engage a diverse population of Black MSM as we work toward HIV elimination in the U.S.

A Longitudinal Examination of Factors Associated with Network Bridging Among YMSM: Implications for HIV Prevention

Social-environmental factors may be associated with social network stability, which has implications for HIV acquisition. However, the link between social-environmental factors, network composition and HIV risk has not been examined previously among a city-population based sample of young Black men who have sex with Men (YBMSM). Respondent driven sampling was used to recruit a cohort of 618 YMBSM. Respondents were evaluated at baseline, 9 and 18 months beginning June 2013. A logistic regression model was used to assess the relationship between bridging (i.e. having non-redundant contacts in one's network, indicating network instability) and social-environmental factors and HIV risk factors between respondents, and a conditional logit model was used to assess these relationships within respondents over time. Bridging was associated with adverse social-environmental factors and higher HIV risk, indicating that bridging may be on the explanatory pathway. Future studies should assess the extent to which network stability factors mitigate HIV risk.

Prescription Opioid Use in a Population-Based Sample of Young Black Men Who Have Sex with Men: A Longitudinal Cohort Study

Background: Prescription opioid use (POU) among young adults is increasing. This represents a major public health concern due to the increased risks of opioid use misuse and opioid-related overdose. Limited research has examined the POU among young black men who have sex with men (YBMSM), a diverse group experiencing continued increases in HIV incidence over the past decade. Objective: This study aims to examine the prevalence and both the individual and network characteristics of POU among YBMSM. Methods: Data were from a longitudinal cohort study of 16-29 year old YBMSM (N = 514) between 2013 and 2016 in Chicago. Bivariate and multivariable associations were estimated using general estimating equations (GEE). Results: Approximately 4.2% of YBMSM reported POU in the past 12 months with a cumulative incidence rate of 4.1% over the 18-month follow-up period. YBMSM having criminal justice involvements, experiencing violence, or using any illicit drug other than marijuana in the past 12 months were more likely to report POU in the past 12 months. The presence of a mother figure, however, was associated with a decreased risk of POU in the past 12 months, while engaging in condomless anal sex with their named sexual partners was associated with an increased risk of POU in the past 12 months. Conclusions: This is one of the first studies to describe POU among a population-based sample of YBMSM. The high incidence rate of POU among YBMSM is alarming, and it underscores the need for further analysis on POU among this key population.

The Social and Sexual Networks of Black Transgender Women and Black Men Who Have Sex with Men: Results from a Representative Sample

Background: Little research has evaluated the social and sexual network-related health outcomes of young black transgender women (TGW) or compared these outcomes with those of black men who have sex with men (MSM). Social network analysis offers one potent means of understanding the dynamics driving the broad spectrum of adverse outcomes experienced by these subgroups.

Methods: We examined the social and sexual health network traits of 618 black individuals assigned male at birth who have sex with men, 47 (7.6%) of whom identified as TGW. Using respondent-driven sampling, data collection occurred over three waves between 2013 and 2016, in Chicago, Illinois. Univariate, logistic regression, and confidant and sexual network analyses were conducted to characterize dynamic network features.

Results: TGW's mean age was 22.1 (standard deviation ±2.6). TGW's sexual networks were significantly less stable (stability ratio of 0.175 vs. 0.278 among MSM, p=0.03) and had greater network turnover (turnover ratio of 0.825 vs. 0.735, p=0.04). TGW also had significantly more sex partners (7.6 vs. 4.0, p=0.0002) and exchange sex (odds ratio=2.97; 95% confidence interval: 1.66–5.32, p<0.001), lower rates of employment (39.6% vs. 71.1%, p<0.001), and more reported an income <$20,000 (93.5% vs. 80.8%, p=0.029). Within confidant networks, TGW had a borderline significantly higher network turnover ratio (0.703 vs. 0.625, p=0.06). Furthermore, both TGW and MSM had high, but similar, HIV rates (42.3% vs. 30.6%, respectively; p=0.17). There were no significant structural network differences vis-à-vis mean degree (p=0.46), betweenness centrality (p=0.40), closeness centrality (p=0.18), or average shortest path length (borderline statistically significant at p=0.06).

Conclusion: Using data from a representative sample of younger black individuals, we observed black TGW have less sexual network stability in contrast to black MSM but comparable structural network features. We further observed that both groups, and black TGW especially, possess considerable system-level, socioeconomic, and sexual health burdens.

Sexual, Social, and Genetic Network Overlap: A Socio-Molecular Approach Toward Public Health Intervention of HIV

OBJECTIVES

To determine how network-level factors influence individual risk of HIV acquisition, which is key in preventing disease transmission.

METHODS

We recruited a cohort of young Black men who have sex with men (n = 618) in Chicago, Illinois, from 2013 to 2016. We identified potential molecular ties via pairwise genetic distance analysis of HIV pol sequences with links inferred between individuals whose sequences were 1.5% or less genetically distant. We defined clusters as 1 or more connections to another individual. We conducted entity resolution between confidant, sexual, referral, and Facebook network data between network types.

RESULTS

Of 266 (43.0%) participants identified as HIV-positive, we obtained 86 (32.3%) genetic sequences. Of these, 35 (40.7%) were linked to 1 or more other sequence; however, none of these were identified in first-, second-, or third-degree confidant and sexual networks. Minimal overlap existed between genetic and Facebook ties.

CONCLUSIONS

These results suggest that HIV transmissions may have occurred before elicitation of network data; future studies should expand the data collection timeframe to more accurately determine risk networks. Virtual network data, such as Facebook, may be particularly useful in developing one's risk environment.

Using Partially-Observed Facebook Networks to Develop a Peer-Based HIV Prevention Intervention: Case Study

Background

This is a case study from an HIV prevention project among young black men who have sex with men. Individual-level prevention interventions have had limited success among young black men who have sex with men, a population that is disproportionately affected by HIV; peer network–based interventions are a promising alternative. Facebook is an attractive digital platform because it enables broad characterization of social networks. There are, however, several challenges in using Facebook data for peer interventions, including the large size of Facebook networks, difficulty in assessing appropriate methods to identify candidate peer change agents, boundary specification issues, and partial observation of social network data.

Objective

This study aimed to explore methodological challenges in using social Facebook networks to design peer network–based interventions for HIV prevention and present techniques to overcome these challenges.

Methods

Our sample included 298 uConnect study respondents who answered a bio-behavioral survey in person and whose Facebook friend lists were downloaded (2013-2014). The study participants had over 180,000 total Facebook friends who were not involved in the study (nonrespondents). We did not observe friendships between these nonrespondents. Given the large number of nonrespondents whose networks were partially observed, a relational boundary was specified to select nonrespondents who were well connected to the study respondents and who may be more likely to influence the health behaviors of young black men who have sex with men. A stochastic model-based imputation technique, derived from the exponential random graph models, was applied to simulate 100 networks where unobserved friendships between nonrespondents were imputed. To identify peer change agents, the eigenvector centrality and keyplayer positive algorithms were used; both algorithms are suitable for identifying individuals in key network positions for information diffusion. For both algorithms, we assessed the sensitivity of identified peer change agents to the imputation model, the stability of identified peer change agents across the imputed networks, and the effect of the boundary specification on the identification of peer change agents.

Results

All respondents and 78.9% (183/232) of nonrespondents selected as peer change agents by eigenvector on the imputed networks were also selected as peer change agents on the observed networks. For keyplayer, the agreement was much lower; 42.7% (47/110) and 35.3% (110/312) of respondent and nonrespondent peer change agents, respectively, selected on the imputed networks were also selected on the observed network. Eigenvector also produced a stable set of peer change agents across the 100 imputed networks and was much less sensitive to the specified relational boundary.

Conclusions

Although we do not have a gold standard indicating which algorithm produces the most optimal set of peer change agents, the lower sensitivity of eigenvector centrality to key assumptions leads us to conclude that it may be preferable. The methods we employed to address the challenges in using Facebook networks may prove timely, given the rapidly increasing interest in using online social networks to improve population health.

Prevalence of and Risk Factors for Anal Human Papillomavirus Infection in a Sample of Young, Predominantly Black Men Who Have Sex With Men, Houston, Texas

Background

Young men who have sex with men (MSM) are at increased risk for human papillomavirus (HPV)-associated disease as a result of HPV infection. Our objective was to characterize the prevalence of high-risk anal HPV infection and factors associated with prevalence in a group of young, primarily black MSM in Houston, Texas.

Methods

MSM aged 18-29 years were recruited using a respondent-driven sampling method to study HIV and sexually transmitted disease transmission and risk. All engaged in peer-recruitment chains and self-collected anal exfoliated cells. Prevalence ratios assessed factors associated with high-risk HPV and HPV types in the 9-valent vaccine.

Results

Black race was reported by 87% of men. Slightly over one half (53%) were human immunodeficiency virus (HIV) positive. Approximately 75% of men had at least 1 high-risk HPV type, and 39% of HIV-positive men harbored HPV-16. Analysis that controlled for potential confounders revealed that only HIV infection was associated with high-risk HPV infection.

Conclusion

Black MSM would benefit from increased HPV vaccination efforts, owing to high rates of HPV infection, increased HPV disease, and low vaccination series completion rates in this population.

Network Viral Load: A Critical Metric for HIV Elimination

BACKGROUND

Associations have been observed between an aggregate viral load measure, the community viral load, and new HIV diagnoses. The community viral load aggregates viral loads within chosen geographic areas, restricting inferences about HIV acquisition risk to these areas. We develop a more precise metric, the network viral load (NVL), to measure the composite viral load within a risk network of a HIV-negative individual.

METHODS

We examined the relationship between NVL and HIV infection among young men who have sex with men in Chicago, United States. Networks were generated using respondent-driven sampling. NVL was defined as the prevalence of viremic individuals in one's risk network, characterized as those with a viral load ≥20 k copies per milliliter. Permutation tests were conducted to account for dependency.

RESULTS

After controlling for total connections, age, substance use during sex, syphilis diagnosis (previous 12 months), and frequency of condomless anal sex (previous 6 months), we found a positive association between NVL and HIV infection. Compared with a network with all HIV-seronegative members, the odds of HIV infection with an NVL of <10% viremia were 1.85 (95% confidence interval: 1.18 to 2.92) times higher and those with an NVL of ≥10% viremia were 2.73 (95% confidence interval: 1.54 to 4.85) times higher.

CONCLUSIONS

We found a positive association between NVL and HIV seroprevalence. Although limited in its ability to infer causality, NVL could have substantial public health implications for persons most at risk for HIV infection, given that this novel metric avoids overreliance on individual level behavior or broad community indices.

Preexposure prophylaxis guidelines have low sensitivity for identifying seroconverters in a sample of young Black MSM in Chicago

BACKGROUND

Identification of clients at greatest risk of acquiring HIV is critical for preexposure prophylaxi (PrEP) implementation. Young black MSM (YBMSM) have high incidence of HIV. We examined published guidelines in identifying eligible PrEP candidates, including seroconverters, in a representative cohort of YBMSM.

METHODS

The uConnect cohort included YBMSM aged 16-29 years during PrEP roll-out in Chicago from 2013 and 2016. YBMSM with indications for PrEP were determined using Center for Disease Control and Prevention (CDC) guidelines, the HIV incidence risk index for MSM (HIRI-MSM) scoring tool, and Gilead recommendations with calculation of sensitivities, specificities, and area under the curve (AUC) for HIV seroconversion over 18 months. Incidence rate ratios (IRRs) using Poisson regression were modeled to compare individual and network factors associated with seroconversion.

RESULTS

In the study cohort, 300 HIV uninfected YBMSM contributed 390.4 person-years of follow-up [mean age (SD), 22.3 years (3.07)]. HIV incidence was 8.5 cases per 100 person-years (95% confidence interval, 6.0-11.9). One network factor was associated with seroconversion: having partners more than 10 years older (IRR = 4.4, 95% confidence interval, 1.6-11.8). Overall, 49% of the cohort had an indication for PrEP using CDC guidelines; 72% using HIRI-MSM, and 86% using Gilead recommendations. HIV seroconverters (n = 33) were identified as PrEP eligible prior to seroconversion with sensitivities/AUCs for CDC (52%/0.51), HIRI-MSM (85%/0.57), and Gilead guidelines (94%/0.54).

CONCLUSION

Low sensitivity of CDC guidelines and limited AUC of HIRI-MSM and Gilead screening tools are of concern for PrEP implementation among most at risk populations such as YBMSM. Consideration of demographics, local epidemiology, and network factors may better guide identification of clients who could benefit most from PrEP.

Project nGage: Results of a Randomized Controlled Trial of a Dyadic Network Support Intervention to Retain Young Black Men Who Have Sex With Men in HIV Care

HIV-positive young black MSM (YBMSM) experience poor outcomes along the HIV care continuum, yet few interventions have been developed expressly for YBMSM retention in care. Project nGage was a randomized controlled trial conducted across five Chicago clinics with 98 HIV-positive YBMSM aged 16-29 between 2012 and 2015. The intervention used a social network elicitation approach with index YBMSM (n = 45) to identify and recruit a support confidant (SC) to the study. Each index-SC dyad met with a social worker to improve HIV-care knowledge, activate dyadic social support, and develop a retention in care plan. Each index and SC also received four mini-booster sessions. Control participants (n = 53) received treatment as usual. Surveys and medical records at baseline, 3-, and 12-months post-intervention assessed visit history (3 or more visits over 12 months; primary outcome), and sociodemographic, network, social-psychological, and behavioral factors. At baseline, there were no differences in age (M = 23.8 years), time since diagnosis (M ≤ 2 years), clinic visits in the previous 12 months (M = 4.1), and medication adherence (68.6 ≥ 90% adherence). In multivariate logistic regression analysis, intervention participants were 3.01 times more likely to have had at least 3 provider visits (95% CI 1.0-7.3) than were control participants over 12 months. Project nGage demonstrates preliminary efficacy in improving retention in care among YBMSM. Results suggest that engaging supportive network members may improve key HIV care continuum outcomes.

At the intersection of criminal justice involvement and sexual orientation: Dynamic networks and health among a population-based sample of young Black men who have sex with men

Mass incarceration of young Black men has a significant impact on their network composition and stability that, in turn, may have major implications for health and well-being. A sub-group of young Black men with criminal justice involvement (CJI) identify as gay, bisexual or are non-identified men who have sex with men (hereafter MSM). This paper focuses on the potential effects of CJI on the composition of Black MSM social and sexual networks, their stability over time, and concomitant health and social outcomes. We use data from the UConnect study, a population-based cohort of young Black MSM 16-29 years of age (n=618) selected using respondent-driven sampling in Chicago from 2013-2016. Both confidant and sexual network name generators and interpreters were administered at 9-month intervals over three waves of data collection. Ego and dyadic-level data were collected on behaviors prevalent among MSM and including factors associated with network CJI, network stability, and health outcomes. Generalized Structural Equation Models (GSEM) were utilized to determine the relationship between CJI network composition, network stability and behaviors prevalent among young Black MSM and their networks. In the UConnect cohort, 46% had at least once been detained, arrested or spent time in jail or prison. In addition, 20% of participants reported incident CJI over the study period. Respondents with a history of CJI were significantly more likely to have CJI homophily in their confidant and sexual networks. Multivariate analyses demonstrate that the association between one's history of CJI, housing instability and drug use is partially explained by one's network CJI. In addition, a higher prevalence of network CJI is associated with increased turnover in the confidant network, and this network instability is also related to important health and social outcomes. This analysis describes the networks of criminal justice involved men among a representative sample of young Black MSM and demonstrates the relationship between CJI network homophily, network stability and their impact on several key health and social outcomes relevant to this population.

Short Communication: Lack of Support for Socially Connected HIV-1 Transmission Among Young Adult Black Men Who Have Sex with Men

We explore the phylogenetic relationships among HIV sequences sampled from young adult black men who have sex with men (YAB-MSM), who are connected through peer referral/social ties and who attend common venues. Using 196 viral sequences sampled from the peripheral blood mononuclear cells of 10 individuals, our preliminary phylogenetic results indicate that these socially connected YAB-MSM are infected with distantly related viruses and provide no evidence for viral transmission between network members. Our results suggest that HIV-prevention strategies that target young adult MSM should extend beyond their network members and local community.