Statistical adjustment of network degree in respondent-driven sampling estimators: venue attendance as a proxy for network size among young MSM

Using Respondent-Driven Sampling (RDS) to Identify the Healthcare Needs among Women of Reproductive Age Who Migrated from Venezuela to Brazil, 2018-2021

In 2021, an RDS survey was conducted among Venezuelan migrant women of reproductive age who migrated to two Brazilian cities (Manaus and Boa Vista) from 2018 to 2021. To start the RDS recruitment, we chose seeds non-randomly in both cities. The study variables were age, educational level, self-rated health, pregnancy, migratory status and use of health services. We estimated the prevalence, confidence intervals and homophily effects by variable category. We used a multivariate logistic regression model to identify the main factors associated with healthcare use. A total of 761 women were recruited in Manaus and 1268 in Boa Vista. Manaus showed more irregular migrants than Boa Vista. The main reasons for using health services were as follows: illness, disease prevention and prenatal care. The logistic regression model showed the use of health services was associated with educational level and healthcare needs but not with migratory status. The social inclusion of Venezuelan migrants is extremely relevant, although many challenges must be overcome. The strategy of the Brazilian Federal Government for providing humanitarian assistance to Venezuelan migrants should be expanded to include and facilitate their integration into labor markets, access to healthcare and education, benefiting both migrants and the Brazilian people by reducing social inequality.

Anal human papillomavirus (HPV) disagreement by Linear Array compared to SPF10 PCR-DEIA-LiPA25 system in young sexual minority men

Introduction

Young sexual minority men (SMM) bear the greatest burden of anal human papillomavirus (HPV) infections. We assessed anal HPV genotype discordance between the Linear Array (LA) and SPF10 PCR-DEIA-LiPA25 (LiPA25).

Methods

Discordance was assessed between LA and LiPA25 using self-collected anal swabs from 120 SMM aged 18-29 who were recruited in 2014-2016. Multiple-type infection was explored as a potential confounder of testing agreement, along with clinical and behavioral factors such as HIV status, syphilis status, incarceration history, health insurance coverage, having 3 or more sex partners in the past 6 months, and co-infection with HPV-16.

Results

Significant discordance was found for HPV-6, -11, -16, -31, -42, -54, and -59. Exploratory analyses suggest higher prevalence of genotype discordance in those living with HIV, those with 3 or more sex partners, and those who were positive for 4 or more HPV types.

Conclusions

Our results highlight the importance of HPV detection methods which may inform different interpretations of research assessing anal HPV natural history among SMM at highest risk for HPV.

Prevalence, Incidence, and Predictors of Kaposi Sarcoma-Associated Herpesvirus Infection Among Young Men Who Have Sex With Men in the Southern United States

Kaposi sarcoma (KS) continues to cause substantial morbidity and mortality in populations at risk in the southern United States. Utilizing biospecimens from the Houston site of the Young Men's Affiliate Project, 351 men who have sex with men had blood tested for KS-associated herpesvirus (KSHV) IgG. Seroprevalence, seroconversion between time points, and demographic and clinical correlates were measured. KSHV prevalence was 36.7% and incidence was 8.9 per 100 person-years. Furthermore, prevalence and incidence were higher among Black individuals, people living with HIV, and those with a history of syphilis. Further research on KSHV risk may improve health disparities in KS diagnosis and outcomes.

Are human papillomavirus knowledge and vaccine uptake associated with HIV status and social determinants of health in young sexual minority men?

This brief report examines the relationship, if any, between human immunodeficiency virus (HIV) status, and individual-level and socio-sexual partner-level factors of social determinants of health (SDOH) that are associated with human papillomavirus (HPV) knowledge and vaccine uptake in young sexual minority men (YSMM). We used data from 126 YSMM recruited by network-based sampling during 2015-2016 in Houston, Texas. Descriptive statistics and regression analyses were conducted to test the association between HIV status, SDOH, and HPV knowledge and vaccine uptake. Those living with HIV had lower odds of knowledge of HPV-associated anal cancer (OR: 0.43, 95% CI: 0.18-0.97) and knowledge of HPV spreading via sexual contact (OR: 0.11, 95% CI: 0.01-0.64), and higher odds of HPV vaccine uptake (OR: 2.90, 95% CI: 1.11-8.02). HPV knowledge and vaccine uptake in YSMM was not associated with partner's attributes or individuals' SDOH factors in our study yet was significantly associated with HIV status. Future interventions are needed to increase HPV knowledge among individuals living with HIV and vaccine uptake particularly among YSMM living without HIV that are not engaged in healthcare.

Awareness and use of HIV pre-exposure prophylaxis and factors associated with awareness among MSM in Beijing, China

Human immunodeficiency virus (HIV) sexual transmission among men who have sex with men (MSM) has increased markedly in Beijing, China in the past decade. Pre-exposure prophylaxis (PrEP) is a highly efficacious biomedical prevention strategy that remarkably reduces HIV-transmission risk. This study examined PrEP awareness among MSM and the factors influencing it. From April to July 2021, respondent-driven sampling was used to conduct a cross-sectional survey among MSM in Beijing, China. Demographic, behavior, and awareness data regarding PrEP were collected. The factors influencing PrEP awareness were assessed using univariate and multivariable logistic regression. In total, 608 eligible responders were included in the study. Among the respondents, 27.9% had PrEP awareness, 3.3% had taken PrEP, and 57.9% expressed interest in receiving PrEP, if required. Greater odds of PrEP awareness were associated with higher education level (adjusted odds ratio [aOR] 3.525, 95% confidence interval [CI] 2.013-6.173, P < 0.0001), greater HIV-related knowledge (aOR 3.605, 95% CI 2.229-5.829, P < 0.0001), HIV testing (aOR 2.647, 95% CI 1.463-4.788, P = 0.0013), and sexually transmitted infections (aOR 2.064, 95% CI 1.189-3.584, P = 0.0101). Lower odds of PrEP awareness were associated with higher stigma score (aOR 0.729, 95% CI 0.591-0.897, P = 0.0029). The findings indicate sub-optimal awareness and low utilization of PrEP in Beijing and highlight PrEP inequities among MSM with stigma. Strengthening the training of peer educators in disseminating PrEP knowledge and reducing stigma are critical for improving PrEP awareness.

Expanding Medicaid to Reduce Human Immunodeficiency Virus Transmission in Houston, Texas: Insights From a Modeling Study

CONTEXT

Medicaid expansion has been nationally shown to improve engagement in the human immunodeficiency virus (HIV) treatment and prevention continua, which are vital steps to stopping the HIV epidemic. New HIV infections in the United States are disproportionately concentrated among young Black men who have sex with men (YBMSM). Houston, TX, is the most populous city in the Southern United States with a racially/ethnically diverse population that is located in 1 of 11 US states that have not yet expanded Medicaid coverage as of 2021.

METHODS

An agent-based model that incorporated the sexual networks of YBMSM was used to simulate improved antiretroviral treatment and pre-exposure prophylaxis (PrEP) engagement through Medicaid expansion in Houston, TX. Analyses considered the HIV incidence (number of new infections and as a rate metric) among YBMSM over the next 10 years under Medicaid expansion as the primary outcome. Additional scenarios, involving viral suppression and PrEP uptake above the projected levels achieved under Medicaid expansion, were also simulated.

RESULTS

The baseline model projected an HIV incidence rate of 4.96 per 100 person years (py) and about 368 new annual HIV infections in the 10th year. Improved HIV treatment and prevention continua engagement under Medicaid expansion resulted in a 14.9% decline in the number of annual new HIV infections in the 10th year. Increasing viral suppression by an additional 15% and PrEP uptake by 30% resulted in a 44.0% decline in new HIV infections in the 10th year, and a 27.1% decline in cumulative infections across the 10 years of the simulated intervention.

FINDINGS

Simulation results indicate that Medicaid expansion has the potential to reduce HIV incidence among YBMSM in Houston. Achieving HIV elimination objectives, however, might require additional effective measures to increase antiretroviral treatment and PrEP uptake beyond the projected improvements under expanded Medicaid.

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.

Stimulant use interventions may strengthen 'Getting to Zero' HIV elimination initiatives in Illinois: Insights from a modeling study

OBJECTIVE(S)

Getting to Zero (GTZ) is an Illinois-based HIV elimination initiative. GTZ identifies younger Black men who have sex with men (YBMSM) as a population who have experienced disproportionate HIV incidence. Rising stimulant use among YBMSM has been determined to impede engagement in the HIV prevention and treatment continua for reducing onward HIV transmission. Given the limited development of dedicated or culturally appropriate interventions for this population, this modeling study explores the impact of stimulant use on HIV incidence among YBMSM and assesses the impact of interventions to treat stimulant use on downstream HIV transmission to achieve GTZ goals.

METHODS

A previously developed agent-based network model (ABNM), calibrated using data for YBMSM in Illinois, was extended to incorporate the impact of stimulant use (methamphetamines, crack/cocaine, and ecstasy) on sexual networks and engagement in HIV treatment and prevention continua. The model simulated the impact of a residential behavioral intervention (BI) for reducing stimulant use and an outpatient biomedical intervention (mirtazapine) for treating methamphetamine use. The downstream impact of these interventions on population-level HIV incidence was the primary intervention outcome.

RESULTS

Baseline simulated annual HIV incidence in the ABNM was 6.93 [95% Uncertainty Interval (UI): 6.83,7.04] per 100 person years (py) and 453 [95% UI: 445.9,461.2] new infections annually. A residential rehabilitation intervention targeted to 25% of stimulant using persons yielded a 27.1% reduction in the annual number of new infections. Initiating about 50% of methamphetamine using persons on mirtazapine reduced the overall HIV incidence among YBMSM by about 11.2%. A 30% increase in antiretroviral treatment (ART) and preexposure prophylaxis (PrEP) uptake in the non-stimulant using YBMSM population combined with a 25% uptake of BI for stimulant using persons produces an HIV incidence consistent with HIV elimination targets (about 200 infections/year) identified in the GTZ initiative.

CONCLUSIONS

Behavioral and biomedical interventions to treat stimulant use, in addition to expanding overall ART and PrEP uptake, are likely to enhance progress towards achieving GTZ goals.

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.

Identifying influential neighbors in social networks and venue affiliations among young MSM: a data science approach to predict HIV infection

OBJECTIVE

Young MSM (YMSM) bear a disproportionate burden of HIV infection in the United States and their risks of acquiring HIV may be shaped by complex multilayer social networks. These networks are formed through not only direct contact with social/sex partners but also indirect anonymous contacts encountered when attending social venues. We introduced a new application of a state-of-the-art graph-based deep learning method to predict HIV infection that can identify influential neighbors within these multiple network contexts.

DESIGN AND METHODS

We used empirical network data among YMSM aged 16-29 years old collected from Houston and Chicago in the United States between 2014 and 2016. A computational framework GAT-HIV (Graph Attention Networks for HIV) was proposed to predict HIV infections by identifying influential neighbors within social networks. These networks were formed by multiple relations constituted of social/sex partners and shared venue attendances, and using individual-level variables. Further, GAT-HIV was extended to combine multiple social networks using multigraph GAT methods. A visualization tool was also developed to highlight influential network members for each individual within the multiple social networks.

RESULTS

The multigraph GAT-HIV models obtained average AUC values of 0.776 and 0.824 for Chicago and Houston, respectively, performing better than empirical predictive models (e.g. AUCs of random forest: 0.758 and 0.798). GAT-HIV on single networks also delivered promising prediction performances.

CONCLUSION

The proposed methods provide a comprehensive and interpretable framework for graph-based modeling that may inform effective HIV prevention intervention strategies among populations most vulnerable to HIV.

Network context matters: graph convolutional network model over social networks improves the detection of unknown HIV infections among young men who have sex with men

OBJECTIVE

HIV infection risk can be estimated based on not only individual features but also social network information. However, there have been insufficient studies using n machine learning methods that can maximize the utility of such information. Leveraging a state-of-the-art network topology modeling method, graph convolutional networks (GCN), our main objective was to include network information for the task of detecting previously unknown HIV infections.

MATERIALS AND METHODS

We used multiple social network data (peer referral, social, sex partners, and affiliation with social and health venues) that include 378 young men who had sex with men in Houston, TX, collected between 2014 and 2016. Due to the limited sample size, an ensemble approach was engaged by integrating GCN for modeling information flow and statistical machine learning methods, including random forest and logistic regression, to efficiently model sparse features in individual nodes.

RESULTS

Modeling network information using GCN effectively increased the prediction of HIV status in the social network. The ensemble approach achieved 96.6% on accuracy and 94.6% on F1 measure, which outperformed the baseline methods (GCN, logistic regression, and random forest: 79.0%, 90.5%, 94.4% on accuracy, respectively; and 57.7%, 80.2%, 90.4% on F1). In the networks with missing HIV status, the ensemble also produced promising results.

CONCLUSION

Network context is a necessary component in modeling infectious disease transmissions such as HIV. GCN, when combined with traditional machine learning approaches, achieved promising performance in detecting previously unknown HIV infections, which may provide a useful tool for combatting the HIV epidemic.

Friend of a Friend with Benefits ontology (FOAF+): extending a social network ontology for public health

BACKGROUND

Dyadic-based social networks analyses have been effective in a variety of behavioral- and health-related research areas. We introduce an ontology-driven approach towards social network analysis through encoding social data and inferring new information from the data.

METHODS

The Friend of a Friend (FOAF) ontology is a lightweight social network ontology. We enriched FOAF by deriving social interaction data and relationships from social data to extend its domain scope.

RESULTS

Our effort produced Friend of a Friend with Benefits (FOAF+) ontology that aims to support the spectrum of human interaction. A preliminary semiotic evaluation revealed a semantically rich and comprehensive knowledge base to represent complex social network relationships. With Semantic Web Rules Language, we demonstrated FOAF+ potential to infer social network ties between individual data.

CONCLUSION

Using logical rules, we defined interpersonal dyadic social connections, which can create inferred linked dyadic social representations of individuals, represent complex behavioral information, help machines interpret some of the concepts and relationships involving human interaction, query network data, and contribute methods for analytical and disease surveillance.

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.

Social Networks and Its Impact on Women's Awareness, Interest, and Uptake of HIV Pre-exposure Prophylaxis (PrEP): Implications for Women Experiencing Intimate Partner Violence

BACKGROUND

In the United States, women represent less than 5% of all pre-exposure prophylaxis (PrEP) users. Social networks may promote and/or inhibit women's PrEP awareness, which could influence PrEP intentions. Furthermore, women experiencing intimate partner violence (IPV) may have smaller, less supportive networks, which could deter or have no impact on PrEP care engagement. This study examined associations between network characteristics and women's PrEP awareness, interest, uptake, and perceived candidacy and analyzed IPV as an effect modifier.

SETTING/METHODS

From 2017 to 2018, data were collected from a prospective cohort study of 218 PrEP-eligible women with (n = 94) and without (n = 124) IPV experiences in Connecticut. Women completed surveys on demographics, IPV, social networks, and PrEP care continuum outcomes.

RESULTS

Adjusted analyses showed that PrEP awareness related to having more PrEP-aware alters. PrEP intentions related to having more alters with favorable opinions of women's potential PrEP use and a smaller network size. Viewing oneself as an appropriate PrEP candidate related to having more PrEP-aware alters and more alters with favorable opinions of women's potential PrEP use. IPV modified associations between network characteristics and PrEP care. Having members who were aware of and/or used PrEP was positively associated with PrEP care engagement for women without IPV experiences but had either no effect or the opposite effect for women experiencing IPV.

CONCLUSION

Improving PrEP attitudes might improve its utilization among women. Social network interventions might be one way to increase PrEP uptake among many US women but may not be as effective for women experiencing IPV.

Network Modeling of PrEP Uptake on Referral Networks and Health Venue Utilization Among Young Men Who Have Sex with Men

The objective of this study is to identify individual-level factors and health venue utilization patterns associated with uptake of pre-exposure prophylaxis (PrEP) and to evaluate whether PrEP uptake behavior is further diffused among young men who have sex with men (YMSM) through health venue referral networks. A sample of 543 HIV-seronegative YMSM aged 16-29 were recruited in 2014-2016 in Chicago, IL, and Houston, TX. Stochastic social network models were estimated to model PrEP uptake. PrEP uptake was associated with more utilization of health venues in Houston and higher levels of sexual risk behavior in Chicago. In Houston, both Hispanic and Black YMSM compared to White YMSM were less likely to take PrEP. No evidence was found to support the spread of PrEP uptake via referral networks, which highlights the need for more effective PrEP referral network systems to scale up PrEP implementation among at-risk YMSM.

Network overlap and knowledge of a partner's HIV status among young men who have sex with men

For individuals living with HIV, disclosure of HIV status to their partners can be a source of psychological and emotional stress. Minimal information about serostatus disclosure is available for young men who have sex with men (YMSM). This study examined the disclosure of HIV status to social and sexual partners among YMSM using social and sexual network data. Respondent-driven sampling was used to collect data from YMSM aged 16-29 in Houston, Texas and Chicago, Illinois. Social network data from 746 respondents and 2035 social and/or sexual partners were collected from 2014 to 2016, of whom 27.9% were HIV seropositive, with 9.4% of their partners being both sexually and socially connected to respondents (overlapping network status), and 90.6% either sexually or socially connected. Generalized estimating equation analysis was conducted based on respondents' knowledge of their sexual partners' HIV status. Results showed that respondents with overlapping sexual and social relationships with their partners were less likely to not know their partners' HIV status (AOR = 0.26 95% CI: 0.18-0.40). Results highlight the association between overlapping partnership and knowledge of partner's HIV status among YMSM. These findings are useful when selecting potential network members to disclose HIV status and support YMSM's health and well-being.