Evaluating the effect of direct-acting antiviral agent treatment scale-up on Hepatitis C virus prevalence among people who inject drugs in UK.

BACKGROUND: There is limited empirical work assessing the effectiveness of treatment as prevention (TasP) in reducing HCV prevalence among people who inject drugs (PWID). Here, we used survey data from the UK during 2010-2020, to evaluate the impact of direct-acting antiviral agent (DAA) treatment scale-up, which started in 2015, on HCV prevalence among PWID. METHODS: We fitted a logistic regression to time/location specific data on prevalence from the Needle Exchange Surveillance Initiative in Scotland and Unlinked Anonymous Monitoring programme in England. For each post-intervention year and location, we quantified the effect of TasP as the difference between estimated prevalence and its counterfactual (prevalence in the absence of scale-up). Progress to elimination was assessed by comparing most recent prevalence against one in 2015. RESULTS: In 2015, prevalence ranged from 0.44 to 0.71 across the 23 locations (3 Scottish, 20 English). Compared to counterfactuals, there was an absolute reduction of 46% (95% credible interval [32%,59%]) in Tayside in 2020, 35% ([24%,44%]) in Glasgow in 2019, and 25% ([10%,39%]) in the Rest of Scotland in 2020. The English sites with highest estimated absolute reductions in 2021 were South Yorkshire (45%, [29%,58%]), Thames Valley (49%, [34%,59%]) and West London (41%, [14%,59%]). Compared to 2015, there was 80% probability that prevalence had fallen by 65% in Tayside, 53% in Glasgow and 36% in the Rest of Scotland. The English sites with highest % prevalence decrease compared to 2015, achieved with probability 80%, were Chesire & Merseyside (70%), South Yorkshire (65%) and Thames Valley (71%). Higher treatment intensity was associated with higher reductions in prevalence. CONCLUSION: Conclusion. Real-world evidence showing substantial reductions in chronic HCV associated with increase of HCV treatment scale-up in the community thus supporting the effectiveness of HCV treatmen as prevention in people who inject drugs.

The Potential Role of Undetectable = Untransmittable (U = U) in Reducing HIV Stigma among Sexual Minority Men in the US.

The Undetectable = Untransmittable (U = U) message and its scientific underpinnings have been widely suggested to reduce HIV stigma. However, misunderstanding and skepticism about U = U may prevent this destigmatizing potential from being fully realized. This cross-sectional study examined associations between U = U belief (belief that someone with a sustained undetectable viral load has zero risk of sexually transmitting HIV) and HIV stigma among US sexual minority men. Differences by serostatus and effects of brief informational messaging were also explored. The survey was completed online by 106 men living with HIV and 351 HIV-negative/status-unknown men (2019-2020). Participants were 18-83 years old (M[SD] = 41[13.0]). Most were non-Hispanic White (70.0%) and gay (82.9%). Although nearly all participants (95.6%) were aware of U = U, only 41.1% believed U = U. A greater percentage of participants living with HIV (66.0%) believed U = U compared with HIV-negative/status-unknown participants (33.6%). Among participants living with HIV, U = U belief was not significantly associated with perceived, internalized, or experienced HIV stigma or with viral load prejudice (prejudice against people who have a detectable HIV viral load). Among HIV-negative/status-unknown participants, U = U belief was associated with less frequently enacted HIV discrimination, more positive feelings toward people with an undetectable viral load, and lower personal endorsement of stigmatizing beliefs. Brief informational messaging about U = U did not affect most stigma dimensions and did not favorably affect any. Interventions are needed to correct commonly held, outdated misconceptions about HIV transmission risk. Such initiatives must not only engage people living with HIV but also engage HIV-negative/status-unknown people to maximize the destigmatizing potential of U = U.

RESUMEN: Para reducir el estigma del VIH se ha recomendado difundir extensivamente el mensaje Indetectable = Intransmisible (U = U) y sus fundamentos científicos. Sin embargo, falta de comprensión y escepticismo acerca de U = U pueden impedir que se realice plenamente su potencial desestigmatizante. Este estudio transversal examinó las asociaciones entre la creencia U = U (creencia de que alguien con una carga viral indetectable sostenida tiene cero riesgo de transmitir sexualmente el VIH) y el estigma del VIH entre hombres de minorías sexuales estadounidenses. También se exploró si el efecto de los mensajes informativos breves dependía del estatus serológico. La encuesta fue completada en línea por 106 hombres que viven con el VIH y 351 hombres VIH negativos o de estatus desconocido (2019­2020). Los participantes tenían entre 18 y 83 años (M[DS] = 41[13,0]). La mayoría eran blancos no hispanos (70,0%) y gay (82,9%). Aunque casi todos los participantes (95,6%) sabían sobre U = U, sólo el 41,1% creían en U = U. Un mayor porcentaje de participantes con VIH (66,0%) creían que U = U en comparación con los participantes VIH negativos o de estatus desconocido (33,6%). Entre los participantes con VIH, la creencia U = U no se asoció significativamente con el estigma del VIH percibido, interiorizado o experimentado ni con el prejuicio sobre la carga viral (prejuicio contra las personas que tienen una carga viral de VIH detectable). Entre los participantes VIH negativos/con estatus desconocido, la creencia U = U se asoció con menor frecuencia de discriminación por VIH, sentimientos más positivos hacia las personas con una carga viral indetectable y menor respaldo personal a las creencias estigmatizantes. Los mensajes informativos breves sobre U = U no afectaron la mayoría de las dimensiones del estigma y no afectó favorablemente a ninguno. Se necesitan intervenciones para corregir conceptos frecuentes sobre el riesgo de transmisión del VIH que son erróneos y obsoletos. Para maximizar el potencial desestigmatizador de U = U, estas iniciativas no sólo deben involucrar a las personas que viven con el VIH, sino también a las personas VIH-negativas o de estatus desconocido.

Evaluating experiences of HIV-related stigma among people living with HIV diagnosed in different treatment eras in British Columbia, Canada.

There is mixed evidence on whether experiences of HIV-related stigma are mitigated with lived experience. We sought to examine whether people living with HIV (PLWH) with longer living experience reported varying levels of HIV-related stigma. Between January 2016-September 2018, we used purposive sampling to enrol PLWH aged ≥19 across British Columbia, Canada, where participants completed the 10-item Berger HIV Stigma Scale. We conducted bivariate analyzes examining key sociodemographic characteristics and HIV-related stigma scores. Multivariable linear regression modelled the association between year of HIV diagnosis by treatment era and HIV-related stigma scores. We enrolled 644 participants; median age at enrolment was 50 years (Q1-Q3: 42-56), with 37.4% (n = 241) diagnosed before the year 2000. The median HIV-stigma scores of all participants (19.0, Q1-Q3: 13-25, range 0-40) stratified by treatment era were: 17.0 (pre-1996), 20.0 (1996-1999), 20.0 (2000-2009), 19.0 (2010-2018) (p = 0.03). While there was a significant association at the univariate level, year of HIV diagnosis by treatment era was not associated with stigma scores after controlling for age, gender, HIV key populations, ethnicity, relationship status, social support, and ever having a mental health disorder diagnosis. This suggests that PLWH still experience HIV-related stigma today, compared to those diagnosed in earlier time periods.

Improving HIV testing, linkage, and retention in care among South African men through U=U messaging: A study protocol for two sequential hybrid type 1 effectiveness- implementation randomized controlled trials.

BACKGROUND: Increasing HIV testing and treatment coverage among people living with HIV (PLHIV) is essential for achieving global AIDS epidemic control. However, compared to women, cis-gender heterosexual men living with HIV are significantly less likely to know their HIV status, initiate anti-retroviral therapy (ART) and achieve viral suppression. This is particularly true in South Africa, where men are also at increased risk of mortality resulting from AIDS-related illnesses. While there is growing knowledge of Treatment as Prevention or the concept Undetectable=Untransmittable (U=U) among PLHIV in Western and high-income countries, the reach and penetration of the U=U message in sub-Saharan Africa remains limited, and few studies have evaluated the impact of accessible and relatable U=U messages on ART initiation and adherence. To address these gaps, rigorous evaluations of interventions that incorporate U=U messages are needed, especially among men in high prevalence settings. METHODS: Building on our U=U messages that we previously developed for men using behavioral economics insights and a human-centered design, we will conduct two sequential hybrid type 1 effectiveness-implementation trials to evaluate the impact of U=U messages on men's uptake of community-based HIV testing and ART initiation (Trial 1), and retention in care and achievement of viral suppression (Trial 2). A cluster randomized trial will be implemented for Trial 1, with HIV testing service site-days randomized to U=U or standard-of-care (SoC) messages inviting men to test for HIV. An individual-level randomized control trial will be implemented for Trial 2, with men initiating ART at six government clinics randomized to receive U=U counselling or SoC treatment adherence messaging. We will incorporate a multi-method evaluation to inform future implementation of U=U messaging interventions. The study will be conducted in the Buffalo City Metro Health District of the Eastern Cape Province and in the Cape Town Metro Health District in the Western Cape Province in South Africa. DISCUSSION: These trials are the first to rigorously evaluate the impact of U=U messaging on HIV testing uptake, ART initiation and achievement of viral suppression among African men. If effective, these messaging interventions can shape global HIV testing, treatment and adherence counselling guidelines and practices.

Biomedical bargains: Negotiating "safe sex" on antiretroviral treatment in rural South Africa.

Wide-scale availability of antiretroviral treatment (ART) has transformed the global landscape for HIV prevention, shifting emphasis away from a strictly behavioral focus on changing sexual practices towards a biomedical approach. Successful ART management is measured by an undetectable viral load, which helps maintain overall health and prevent onward viral transmission. The latter utility of ART, however, must be understood in the context of its implementation. In South Africa, ART has become easily accessible - yet ART knowledge spreads unevenly, while counseling advice and normative expectations and experiences of gender and aging interact to inform sexual practices. As ART enters the sexual lives of middle-aged and older people living with HIV (MOPLH), a population growing rapidly, how has it informed sexual decisions and negotiations? Drawing on in-depth interviews with MOPLH on ART, corroborated with focus group discussions and national ART-related policies and guidelines, we find that for MOPLH, sexual decisions increasingly feature compliance with biomedical directives and concern for ART efficacy. Seeking consensus regarding the biological risks of sex on ART becomes an important feature of sexual negotiations, and anticipated disagreements can pre-empt sexual relationships altogether. We introduce the concept of biomedical bargains to explain what happens when disagreements arise, and the terms of sex are negotiated using competing interpretations of biomedical information. For both men and women, ostensibly gender-neutral biomedical discourses provide new discursive resources and strategies for sexual decisions and negotiations, yet biomedical bargains are still embedded in gender dynamics-women invoke the dangers of jeopardizing treatment efficacy and longevity to insist on condoms or justify abstinence, while men utilize biomedical arguments in an effort to render condomless sex safe. While the full therapeutic benefits of ART are critical for the efficacy and equity of HIV programs, they will nonetheless always affect, and be affected by, social life.

Healthcare and treatment experiences among people diagnosed with HIV before and after a province-wide treatment as prevention initiative in British Columbia, Canada.

INTRODUCTION: In 2010, the Canadian province of British Columbia (BC) initiated the Seek and Treat for Optimal Prevention of HIV/AIDS (STOP HIV/AIDS) program to improve HIV testing, linkage to care, and treatment uptake, thereby operationalizing the HIV Treatment as Prevention (TasP) framework at the population-level. In this analysis, we evaluated self-reported HIV care experiences and therapeutic outcomes among people diagnosed with HIV prior to and after implementation of this provincial program. METHODS: A cross-sectional analysis was performed on the baseline data of a cohort of people living with HIV (PLWH) (19 years and older) in the province of BC sampled from July 2016 to September 2018. All participants consented to linking their survey data to the provincial HIV treatment registry. Individuals diagnosed with HIV from January 1 2000-December 31 2009 were classified as pre-intervention and those diagnosed January 1 2010-December 31 2018 as post-intervention cohorts. Bivariate analyses were run using Chi-square and Wilcoxon Rank Sum tests. Cox proportional hazards regression model demonstrates time to antiretroviral therapy (ART) initiation (from HIV baseline) and virological suppression (2 consecutive plasma viral load measurements < 200 copies/ml). RESULTS: Of the 325 participants included in this analysis, 198 (61%) were diagnosed with HIV in the pre-intervention era and 127 (39%) in the post-intervention era. A higher proportion of participants in post-intervention era were diagnosed at walk-in clinics (45% vs. 39%) and hospitals (21% vs. 11%) (vs pre-intervention) (p = 0.042). Post-intervention participants had initiated ART with less advanced HIV disease (CD4 count 410 vs. 270 cells/ul; p = 0.001) and were less likely to experience treatment interruptions at any point in the 5 years after HIV diagnosis (17% vs. 48%; p < 0.001). The post-intervention cohort had significantly more timely ART initiation (aHR: 5.97, 95%CI 4.47, 7.97) and virologic suppression (aHR: 2.03, 95%CI 1.58, 2.60) following diagnosis, after controlling for confounders. CONCLUSIONS: We found favourable treatment experiences and more timely ART initiation and virologic suppression after a targeted TasP provincial program. Our results illustrate the importance of accessible low-barrier HIV testing and treatment in tackling the HIV epidemic.

Sexual and Relationship Benefits of a Safer Conception Intervention Among Men with HIV Who Seek to Have Children with Serodifferent Partners in Uganda.

Many men with HIV (MWH) in Uganda desire children, yet seldom receive reproductive counseling related to HIV care. Because men are under engaged in safer conception programming, they miss opportunities to reap the benefits of these programs. The objective of this sub-analysis was to explore the relationship and intimacy benefits of integrating safer conception counseling and strategies into HIV care, an emergent theme from exit interviews with men who participated in a pilot safer conception program and their partners. Twenty interviews were conducted with MWH who desired a child in the next year with an HIV-uninfected/status unknown female partner, and separate interviews were conducted with female partners (n = 20); of the 40 interviews, 28 were completed by both members of a couple. Interviews explored experiences participating in The Healthy Families program, which offered MWH safer conception counseling and access to specific strategies. Data were analyzed using thematic analysis. Three major subthemes or "pathways" to the relationship and intimacy benefits associated with participation in the program emerged: (1) improved dyadic communication; (2) joint decision-making and power equity in the context of reproduction; and (3) increased sexual and relational intimacy, driven by reduced fear of HIV transmission and relationship dissolution. These data suggest that the intervention not only helped couples realize their reproductive goals; it also improved relationship dynamics and facilitated intimacy, strengthening partnerships and reducing fears of separation. Directly addressing these benefits with MWH and their partners may increase engagement with HIV prevention strategies for conception.

HIV Serostatus Disclosure Among Men Who Have Sex with Men in China in the Era of U=U and PrEP.

Given the recent evidence on "Undetectable = Untransmittable" (U=U) and pre-exposure prophylaxis (PrEP), the present study aimed to investigate HIV disclosure behaviors and their associations with sexual risk behaviors and U=U and PrEP awareness among men who have sex with men (MSM) in China. A cross-sectional survey was conducted among 689 MSM recruited through a gay-friendly non-governmental organization located in Chengdu, China in 2018-2019. Information was collected by a structured self-administrated questionnaire. The enrolled sample included 554 (80.4%) participants who were HIV-negative and 135 (19.6%) participants with an unknown HIV status. In terms of disclosure, 41.4% of participants informed all partners about their HIV status all the time (informing behavior), while 30.4% asked all partners about their HIV status all the time (asking behavior). Only one-fifth knew about U=U, but this was not statistically associated with either informing or asking behavior. Half (50.5%) had heard of PrEP but this was not statistically associated with either informing or asking behavior. Common barriers to informing and asking behaviors were lower risk perception of HIV infection, a history of sexually transmitted infections, engagement in receptive sex, and a history of sex with casual partners. We found that both U=U and PrEP awareness and HIV serostatus disclosure were infrequent and not associated in this study of Chinese MSM. These data indicate huge information gaps among MSM in China.

The success of HIV combination prevention: The Dean Street model.

The 56 Dean Street combination prevention model, a strong engagement with the LGBTQI community and flexible services adapted to users' changing needs led to an 80% drop in HIV diagnoses in gay, bisexual and other men who have sex with men (GBMSM) from 2015 to 2017. We describe the service changes at 56 Dean Street since 2012 which resulted in an increase in the frequency of HIV testing, the introduction of pre-exposure prophylaxis, earlier HIV diagnosis and a shorter time to viral suppression in those living with HIV. This model could be adapted to deliver similar results in those settings of high HIV prevalence among GBMSM and where access to technological innovation in healthcare and engagement with the community can be achieved.

A Behavioral Cascade of HIV Seroadaptation Among US Men Who Have Sex with Men in the Era of PrEP and U = U.

Seroadaptive behaviors help reduce HIV risk for some men who have sex with men (MSM), and have been well documented across MSM populations. Advancements in biomedical prevention have changed the contexts in which seroadaptive behaviors occur. We thus sought to estimate and compare the prevalence of four stages of the "seroadaptive cascade" by PrEP use in the recent era: knowledge of own serostatus, knowledge of partner serostatus; serosorting (matching by status), and condomless anal intercourse. Serosorting overall appeared to remain common, especially with casual and one-time partners. Although PrEP use did not impact status discussion, it did impact serosorting and the likelihood of having condomless anal intercourse. For respondents not diagnosed with HIV and not on PrEP, condomless anal intercourse occurred in just over half of relationships with HIV-positive partners who were not on treatment. Biomedical prevention has intertwined with rather than supplanted seroadaptive behaviors, while contexts involving neither persist.

RESUMEN: Los comportamientos seroadaptivos ayudan a reducir el riesgo de VIH en algunos hombres que tienen sexo con otros hombres (HSH) y han sido bien documentados en varias comunidades de HSH. Los avances en prevención biomédica han cambiado los contextos de los comportamientos seroadaptivos. Por ello buscamos estimar y comparar la prevalencia de cuatro fases de la 'cascada seroadaptiva' mediante el uso de PrEP en la era reciente: conocimiento del seroestatus personal, conocimiento del seroestatus del compañero, serosorting (emparejamiento por estatus) y coito anal sin condón. En general, el serosorting parece seguir siendo común especialmente con parejas casuales o de una noche. A pesar de que el uso de PrEP no impactó la discusión sobre el estatus, sí impactó el serosorting y la probabilidad de coito anal sin condón. Los encuestados no diagnosticados con VIH y sin PrEP tuvieron coito anal sin condón en la mitad de las relaciones con parejas VIH-positivo que no estaban bajo tratamiento. La prevención biomédica se ha entremezclado en lugar de suplantar los comportamientos seropositivos, mientras persisten los contextos en los que no aparece ninguno.

Stages of Adoption of "Treatment as Prevention" Among HIV-Negative Men Who Have Sex with Men Who Engage in Exchange Sex.

Prior research found low acceptability of HIV treatment as prevention (TasP; or Undetectable = Untransmittable) among HIV-negative men who have sex with men (MSM). This study reports on qualitative data regarding TasP adoption in a sample of 170 self-reported HIV-negative MSM who had engaged in exchange sex (received money, drugs, or other things in exchange for sex). We classified participants along five stages of TasP adoption: 1-unaware of TasP (11.2%); 2-aware, but perceived ineffective (17.1%); 3-perceived effective, but unwilling to use (35.3%); 4-willing to rely on TasP, but had never done so (24.1%); and 5-had relied on TasP (12.4%). Obstacles to TasP adoption included the following: not believing that it could completely prevent HIV transmission; deeply ingrained fears of HIV/AIDS; concerns about viral load fluctuation; and reluctance to trust a partner's claimed undetectable status. TasP promotion efforts, which can decrease barriers to HIV testing and HIV stigma, will be more effective if tailored to the obstacles specific to each stage of TasP adoption.

Awareness and Perceived Effectiveness of HIV Treatment as Prevention Among Men Who Have Sex with Men in New York City.

To assess perceptions of HIV treatment as prevention (TasP), we conducted an online survey of MSM in New York City (n = 732) asking them to rate the effectiveness of different strategies to reduce HIV risk during serodiscordant condomless anal sex between men. Only 6.1% reported not knowing what TasP was, with significantly less awareness among non-gay-identified MSM, men with less education, men who reported fewer anal sex partners in the prior 3 months, and HIV-negative/unaware men who had never used PrEP. The strategy most frequently perceived to offer "a lot" or "complete" protection from HIV was daily PrEP (70.0%), followed by TasP (39.1%), intermittent PrEP (16.6%), strategic positioning (15.8%), and withdrawal before ejaculation (10.8%). Men who were HIV positive, who had ever used PrEP, and who identified as gay/homosexual were significantly more likely to see TasP as effective. Further studies should investigate MSM's apparent skepticism towards TasP.

"I Wasn't in My Right Mind": Qualitative Findings on the Impact of Alcohol on Condom Use in Patients Living with HIV/AIDS in Brazil, Thailand, and Zambia (HPTN 063).

PURPOSE: There have been significant biomedical improvements in the treatment and prevention of HIV over the past few decades. However, new transmissions continue to occur. Alcohol use is a known barrier to medication adherence and consistent condom use and therefore may affect treatment as prevention (TasP) efforts. The purpose of this study was to further explore how alcohol is associated with condom use and sexual transmission behavior in three international cities. METHOD: HIV Prevention Trials Network 063 was an observational mixed-methods study of HIV-infected patients currently in care in Rio de Janeiro, Brazil; Chiang Mai, Thailand; and Lusaka, Zambia. Across these three global cities, 80 qualitative interviews were conducted from 2010 to 2012. From these interviews, quotes related to substance use, almost all of which were alcohol, were analyzed using thematic analysis to identify how the use was related to sexual transmission behaviors. RESULTS: Overall, the theme that alcohol impairs cognitive abilities emerged from the data and included the following subthemes: expectancies, impaired decision-making, loss of control, and less concern for others. Themes specific to international settings and risk subgroups were also identified. CONCLUSION: Our analysis identified how alcohol influences sexual transmission behavior in HIV patients in three international settings. These findings may provide direction for content development for future secondary prevention interventions to effectively implement TasP internationally.

Treatment as Prevention for HIV Infection: Current Data, Challenges, and Global Perspectives

In 2008, the Swiss National AIDS Commission issued a statement about the safety of HIV treatment in terms of reduced transmission in serodiscordant couples to reduce transmission in serodiscordant couples. This was subjected to debate until 2011 when the HIV prevention trial network 052 published the first randomized study about HIV transmission in serodiscordant couples, where no transmission was observed when the infected person was under effective antiretroviral treatment (ART). Later, the Partners of People on ART-A New Evaluation of the Risks (PARTNER) and the opposites attract studies, which first involved a large number of men who have sex with men (MSM), also showed no transmission, even in condomless receptive anal intercourse (CLAI). In this article, we first review the major studies' data showing the efficacy of ART in HIV transmission in serodiscordant couples at public health scale. Second, we discuss the implications and challenges behind the treatment as prevention strategy regarding the 90-90-90 UNAIDS targets to end the HIV epidemic.We now have strong evidence that ART reduces the risk of transmission of HIV from a positive partner to their negative partner. However, far beyond ART, combining prevention policies is crucial to avoid a new increase in the overall HIV incidence.

Biomedical Approaches to HIV Prevention in Women.

PURPOSE OF REVIEW: Effective HIV prevention techniques for women are of critical importance, as nearly half of all HIV infections globally are in women. This article reviews the recent literature on biomedical approaches to HIV prevention in women. RECENT FINDINGS: In trials in which women were adherent to oral pre-exposure prophylaxis (PrEP), PrEP was equally efficacious in men and women. However, in studies of oral PrEP exclusively in women, adherence was low, and it was not efficacious. In trials of topical PrEP, including vaginal tenofovir gel and the monthly dapivirine ring, efficacy was also dependent upon adherence. Treatment as prevention (TasP) is a very effective HIV prevention strategy, though limited in that it is not controlled by the HIV-uninfected partner. Adherence is an important factor in the efficacy of biomedical interventions for HIV prevention in women; continued research is needed to identify the most efficacious and acceptable agents for women. Oral PrEP is currently recommended for the following groups of HIV-negative women: heterosexual women in ongoing sexual relationships with a partner infected with or at substantial risk of HIV infection and women who inject drugs and share injection or drug preparation equipment.

Prevalence of and Factors Associated with the Use of HIV Serosorting and Other Biomedical Prevention Strategies Among Men Who Have Sex with Men in a US Nationwide Survey.

PrEP and treatment-as-prevention (TasP) are biomedical strategies to reduce HIV transmission. Some men who have sex with men (MSM) are combining biomedical strategies with HIV serosorting-termed "biomed matching" when both partners are either on PrEP or TasP, or "biomed sorting" when one partner is using PrEP and the other TasP. Nevertheless, there is limited data on the extent of biomed matching/sorting in large geographically diverse samples. In 2016-2017, 5021 MSM from across the US were surveyed about their HIV status and HIV viral load/PrEP use, as well as that of their recent casual male partners. For each participant, we calculated the proportion of his partners who were (1) HIV-positive and undetectable, (2) HIV-positive and detectable/unknown, (3) HIV unknown/undiscussed, (4) HIV-negative on PrEP, (5) HIV-negative, not on PrEP. In total, 66.6% (n = 3346) of participants were HIV-negative and not on PrEP, 11.9% (n = 599) on PrEP, 14.1% (n = 707) HIV-positive and undetectable, 1.1% (n = 55) HIV-positive and viral load detectable/unknown, and 6.2% (n = 313) HIV unsure/unknown. A participant's own HIV and PrEP status/was significantly associated with that of his partners (all p < 0.001), evincing evidence of both serosorting and biomed matching. Among men on PrEP and those who were HIV-undetectable, there was also some evidence to suggest these participants dually engaged in biomed matching as well as biomed sorting. We found evidence of biomed matching and sorting, which may compound its effectiveness for those using it (i.e., both partners bring biomedical protection). Unintended consequences of biomed matching/sorting include that men not using a biomedical strategy may be less likely to benefit from a partner's use of the strategy-potentially further driving disparities in HIV infections. Public health campaigns might be well served to highlight not only the benefits that biomedical HIV prevention strategies provide for their users (e.g., "being on PrEP protects me from getting HIV"), but also the benefits that a user brings to his partners (e.g., "my use of PrEP means my partners won't get HIV"), and the benefits of being with a partner who is using a biomedical strategy (e.g., "my partner's use of PrEP/TasP protects me from HIV").

HIV treatment optimism and crystal methamphetamine use and initiation among HIV-negative men who have sex with men in Vancouver, Canada: A longitudinal analysis.

BACKGROUND: Treatment as Prevention (TasP) leading to increased HIV treatment optimism among men who have sex with men (MSM) has been previously associated with behavioural risk compensation, though not yet via crystal methamphetamine (CM) use. Among HIV-negative MSM in a TasP environment, this study aimed to investigate the prevalence of recent CM use over time, examine the association between HIV treatment optimism and CM use and initiation, and identify correlates of recent CM use and predictors of CM initiation. METHODS: Using data from a prospective behavioural cohort study of sexually active MSM in the Vancouver area, we used multi-level generalized mixed effect models to evaluate temporal trends in CM use, univariable and multivariable logistic regression to identify covariates of recent CM use, and univariable and multivariable survival analysis to identify predictors of CM initiation. RESULTS: Of 497 HIV-negative cohort participants, 10.3% reported any recent CM use at enrollment. From 2012-2016, there were no statistically significant temporal trends in overall CM use or with routes of administration. In multivariable logistic regression analyses, HIV treatment optimism was not associated with recent CM use (not retained in final model) or CM initiation (aHR = 1.06, 95% CI:0.98-1.15). Significant correlates of CM use include recent gamma-hydroxybutyrate (GHB) and ecstasy use, and having received/given drugs for sex. CONCLUSIONS: Among HIV-negative MSM in Vancouver, HIV treatment optimism does not appear to be independently associated with CM use or initiation of use, though use of CM was both prevalent and stable over time.