Social determinants of health and retention in HIV care in a clinical cohort in Ontario, Canada.

Continuous HIV care supports antiretroviral therapy initiation and adherence, and prolongs survival. We investigated the association of social determinants of health (SDH) and subsequent retention in HIV care in a clinical cohort in Ontario, Canada. The Ontario HIV Treatment Network Cohort Study is a multi-site cohort of patients at 10 HIV clinics. Data were collected from medical charts, interviews, and via record linkage with the provincial public health laboratory for viral load tests. For participants interviewed in 2009, we used three-category multinomial logistic regression to identify predictors of retention in 2010-2012, defined as (1) continuous care (≥2 viral loads ≥90 days in all years; reference category); (2) discontinuous care (only 1 viral load/year in ≥1 year); and (3) a gap in care (≥1 year in 2010-2012 with no viral load). In total, 1838 participants were included. In 2010-2012, 71.7% had continuous care, 20.9% had discontinuous care, and 7.5% had a gap in care. Discontinuous care in 2009 was predictive (p < .0001) of future retention. SDH associated with discontinuous care were Indigenous ethnicity, being born in Canada, being employed, reporting hazardous drinking, and non-injection drug use. Being a heterosexual male was associated with having a gap in care, and being single and younger were associated with discontinuous care and a gap in care. Various SDH were associated with retention. Care discontinuity was highly predictive of future gaps. Targeted strategic interventions that better engage those at risk of suboptimal retention merit exploration. ABBREVIATIONS: AOR: adjusted odds ratio; ART: antiretroviral therapy; AUDIT: Alcohol Use Disorders Identification Test; CES-D: Center for Epidemiologic Studies Depression Scale; CIs: confidence intervals; HIV: human immunodeficiency virus; IQR: interquartile range; MSM: men who have sex with men; NA-ACCORD: North American AIDS Cohort Collaboration on Research and Design; OCS: Ontario HIV Treatment Network Cohort Study; OHTN: Ontario HIV Treatment Network; OR: odds ratio; PHOL: Public Health Ontario Laboratories; REB: Research Ethics Board; SDH: social determinants of health; US: United States.

Serosorting and recreational drug use are risk factors for diagnosis of genital infection with chlamydia and gonorrhoea among HIV-positive men who have sex with men: results from a clinical cohort in Ontario, Canada.

OBJECTIVES: Rates of chlamydia and gonorrhoea have been rising in urban centres in Canada, particularly among HIV-positive men who have sex with men (MSM). Our objective was to identify behavioural risk factors for diagnosis with chlamydia and gonorrhoea in this population, with a focus on the HIV status of sexual partners. METHODS: The OHTN Cohort Study follows people in HIV care across Ontario. We restricted the analysis to 1997 MSM who completed questionnaires in 2010-2013 at one of seven clinics that submit all chlamydia and gonorrhoea tests to the provincial public health laboratory; we obtained test results via record linkage. We estimated cumulative incidences using Kaplan-Meier methods and identified risk factors for diagnosis of a composite outcome (chlamydia or gonorrhoea infection) using Cox regression. RESULTS: At follow-up, there were 74 new chlamydia/gonorrhoea diagnoses with a 12-month cumulative incidence of 1.7% (95% CI 1.1% to 2.2%). Risk factors for chlamydia/gonorrhoea diagnosis were: 5+ HIV-positive partners (HR=3.3, 95% CI 1.4 to 7.8; reference=none) and recreational drug use (HR=2.2, 95% CI 1.2 to 3.9). CONCLUSIONS: Heightened risks with recreational drug use and multiple HIV-positive partners suggest that chlamydia/gonorrhoea may have achieved high prevalence in certain sexual networks among HIV-positive MSM. Interventions to promote safer sex and timely testing among MSM are needed.

Economic Evaluation of Community-Based HIV Prevention Programs in Ontario: Evidence of Effectiveness in Reducing HIV Infections and Health Care Costs.

Investments in community-based HIV prevention programs in Ontario over the past two and a half decades are assumed to have had an impact on the HIV epidemic, but they have never been systematically evaluated. To help close this knowledge gap, we conducted a macro-level evaluation of investment in Ontario HIV prevention programs from the payer perspective. Our results showed that, from 1987 to 2011, province-wide community-based programs helped to avert a total of 16,672 HIV infections, saving Ontario's health care system approximately $6.5 billion Canadian dollars (range 4.8-7.5B). We also showed that these community-based HIV programs were cost-saving: from 2005 to 2011, every dollar invested in these programs saved about $5. This study is an important first step in understanding the impact of investing in community-based HIV prevention programs in Ontario and recognizing the impact that these programs have had in reducing HIV infections and health care costs.

Implementation and Operational Research: Engagement in HIV Care Among Persons Enrolled in a Clinical HIV Cohort in Ontario, Canada, 2001-2011.

BACKGROUND: Ensuring that people living with HIV are accessing and staying in care is vital to achieving optimal health outcomes including antiretroviral therapy (ART) success. We sought to characterize engagement in HIV care among participants of a large clinical cohort in Ontario, Canada, from 2001 to 2011. METHODS: The Ontario HIV Treatment Network Cohort Study (OCS) is a multisite HIV clinical cohort, which conducts record linkage with the provincial public health laboratory for viral load tests. We estimated the annual proportion meeting criteria for being in care (≥1 viral load per year), in continuous care (≥2 viral load per year ≥90 days apart), on ART, and with suppressed viral load <200 copies per milliliter. Ratios of proportions according to socio-demographic and clinical characteristics were examined using multivariable generalized estimating equations with a log-link. RESULTS: A total of 5380 participants were followed over 44,680 person-years. From 2001 to 2011, we observed high and constant proportions of patients in HIV care (86.3%-88.8%) and in continuous care (76.4%-79.5%). There were statistically significant rises over time in the proportions on ART and with suppressed viral load; by 2011, a majority of patients were on ART (77.3%) and had viral suppression (76.2%). There was minimal variation in HIV engagement indicators by socio-demographic and HIV risk characteristics. CONCLUSIONS: In a setting with universal health care, we observed high proportions of HIV care engagement over time and an increased proportion of patients attaining successful virologic suppression, likely due to improvements in ART regimens and changing guidelines.

High incidence of diagnosis with syphilis co-infection among men who have sex with men in an HIV cohort in Ontario, Canada.

BACKGROUND: The re-emergence of syphilis among HIV-positive gay and other men who have sex with men (MSM) requires vigilance. We estimated incidence of and risk factors for first and subsequent syphilis diagnoses among MSM in HIV care in Ontario, Canada. METHODS: We analyzed data from 2,280 MSM under follow-up from 2006 to 2010 in the Ontario HIV Treatment Network Cohort Study (OCS), a multi-site clinical cohort. We obtained syphilis serology results via record linkage with the provincial public health laboratory. Rates were calculated using Poisson regression. RESULTS: First syphilis diagnoses occurred at a rate of 2.0 per 100 person-years (95 % CI 1.7, 2.4; 121 cases) whereas the re-diagnosis rate was 7.5 per 100 person-years (95 % CI 6.3, 8.8; 136 cases). We observed higher rates over time and among men who were aged <30 years, receiving care in the two largest urban centers, or had a previous syphilis diagnosis. Syphilis diagnosis was less common among Indigenous men, men with higher CD4 cell counts, and, for first diagnoses only, among men with less than high school education. CONCLUSIONS: Compared to reported cases in the general male population, incidence of a new syphilis diagnosis was over 300 times greater among HIV-positive MSM but year-to-year changes reflected provincial trends. Re-diagnosis was common, suggesting treatment failure or re-infection. Novel syphilis control efforts are needed among HIV-positive MSM.

Hepatitis C virus seroconversion among HIV-positive men who have sex with men with no history of injection drug use: Results from a clinical HIV cohort.

BACKGROUND: Internationally, there is a growing recognition that hepatitis C virus (HCV) may be sexually transmitted among HIV-positive men who have sex with men (MSM). OBJECTIVE: To report the first Canadian estimate of HCV seroincidence in 2000 to 2010 and its risk factors among HIV-positive MSM with no known history of injection drug use. METHODS: Data from the Ontario HIV Treatment Network Cohort Study, an ongoing cohort of individuals in HIV care in Ontario, were analyzed. Data were obtained from medical charts, interviews and record linkage with the provincial public health laboratories. The analysis was restricted to 1534 MSM who did not report injection drug use and had undergone ≥2 HCV antibody tests, of which the first was negative (median 6.1 person-years [PY] of follow-up; sum 9987 PY). RESULTS: In 2000 to 2010, 51 HCV seroconversions were observed, an overall incidence of 5.1 per 1000 PY (95% CI 3.9 to 6.7). Annual incidence varied from 1.6 to 8.9 per 1000 PY, with no statistical evidence of a temporal trend. Risk for seroconversion was elevated among men who had ever had syphilis (adjusted HR 2.5 [95% CI 1.1 to 5.5) and men who had acute syphilis infection in the previous 18 months (adjusted HR 2.8 [95% CI 1.0 to 7.9]). Risk was lower for men who had initiated antiretroviral treatment (adjusted HR 0.49 [95% CI 0.25 to 0.95]). There were no statistically significant effects of age, ethnicity, region, CD4 cell count or HIV viral load. CONCLUSIONS: These findings suggest that periodic HCV rescreening may be appropriate in Ontario among HIV-positive MSM. Future research should seek evidence whether syphilis is simply a marker for high-risk sexual behaviour or networks, or whether it potentiates sexual HCV transmission among individuals with HIV.

HISTORIQUE: Sur la scène internationale, il apparaît de plus en plus clairement que le virus de l'hépatite C (VHC) peut être transmis sexuellement entre hommes positifs au VIH ayant des relations sexuelles avec des hommes (HARSAH). OBJECTIF: Rendre compte de la première estimation canadienne de la séro-incidence de VHC entre 2000 et 2010 et de ses facteurs de risque chez les HARSAH positifs au VIH sans antécédents connus de consommation de drogues injectables. MÉTHODOLOGIE: Les chercheurs ont analysé les données de l'Ontario HIV Treatment Network Cohort Study, une cohorte continue de personnes soignées pour le VIH en Ontario. Ils ont tiré les données de dossiers médicaux, d'entrevues et de liens entre les dossiers et les laboratoires provinciaux de santé publique. Ils ont restreint l'analyse à 1 534 HARSAH qui ne déclaraient pas consommer de drogues injectables et qui avaient subi au moins deux tests d'anticorps du VHC, dont le premier était négatif (suivi médian de 6,1 années-personne [AP]; somme de 9 987 AP). RÉSULTATS: De 2000 à 2010, les chercheurs ont observé 51 cas de séroconversion au VHC, pour une incidence globale de 5,1 cas sur 1 000 AP (95 % IC 3,9 à 6,7). L'incidence annuelle variait entre 1,6 et 8,9 cas sur 1 000 AP, sans preuve statistique de tendance temporelle. Le risque de séroconversion était élevé chez les hommes qui n'avaient jamais eu la syphilis (RR rajusté 2,5 [95 % IC 1,1 à 5,5) et chez les hommes qui avaient eu une infection aiguë par la syphilis dans les 18 mois précédents (RR rajusté 2,8 [95 % IC 1,0 à 7,9]). Le risque était plus faible chez les hommes qui avaient entrepris un traitement anti-rétroviral (RR rajusté 0,49 [95 % IC 0,25 à 0,95]). L'âge, l'ethnie, la région, la numération des cellules CD4 et la charge virale du VIH n'avaient pas d'effet statistiquement significatif. CONCLUSIONS: D'après ces observations, il serait judicieux de procéder au dépistage périodique du VHC chez les HARSAH positifs au VIH de l'Ontario. De prochaines recherches devraient viser à établir si la syphilis est un simple marqueur de comportements ou de réseaux sexuels à haut risque ou si elle potentialise la transmission sexuelle du VHC chez les personnes atteintes du VIH.

Modest rise in chlamydia and gonorrhoea testing did not increase case detection in a clinical HIV cohort in Ontario, Canada.

OBJECTIVES: We described patterns of testing for chlamydia and gonorrhoea infection among persons in specialty HIV care in Ontario, Canada, from 2008 to 2011. METHODS: We analysed data from 3165 participants in the OHTN Cohort Study attending one of seven specialty HIV care clinics. We obtained chlamydia and gonorrhoea test results via record linkage with the provincial public health laboratory. We estimated the proportion of participants who underwent testing annually, the positivity rate among those tested and the proportion diagnosed with chlamydia or gonorrhoea among all under observation. We explored risk factors for testing and diagnosis using multiple logistic regression analysis. RESULTS: The proportion tested annually rose from 15.2% (95% CI 13.6% to 16.7%) in 2008 to 27.0% (95% CI 25.3% to 28.6%) in 2011 (p<0.0001). Virtually all were urine-based nucleic acid amplification tests. Testing was more common among men who have sex with men (MSM), younger adults, Toronto residents, persons attending primary care clinics and persons who had tested in the previous year or who had more clinic visits in the current year. We observed a decrease in test positivity rates over time. However, the annual proportion diagnosed remained stable and in 2011 this was 0.97% (95% CI 0.61% to 1.3%) and 0.79% (95% CI 0.46% to 1.1%) for chlamydia and gonorrhoea, respectively. Virtually all cases were among MSM. CONCLUSIONS: Chlamydia and gonorrhoea testing increased over time while test positivity rates declined and the overall proportion diagnosed remained stable, suggesting that the modest increase in testing did not improve case detection.

Patterns of syphilis testing in a large cohort of HIV patients in Ontario, Canada, 2000-2009.

BACKGROUND: Since 2000, reported syphilis cases increased ten-fold in Canada, particularly among men who have sex with men (MSM) co-infected with HIV. We characterized temporal patterns of of syphilis testing in a large cohort of HIV patients in Ontario, Canada. METHODS: We analyzed data from a multi-site cohort of people in HIV care from 2000 to 2009. Data were obtained from medical charts, interviews and record linkage with the syphilis test database at the Public Health Ontario Laboratories. We estimated the proportion that had syphilis testing at least once per year and the period and annual prevalence of reactive tests. RESULTS: Among 4232 participants, the annual proportion tested rose from 2.7% (95%CI 1.9, 3.5) in 2000 to 54.6% (95%CI 52.9, 56.3) in 2009. Testing was most common for participants who were men who have sex with men (MSM), aged <30, recently diagnosed with HIV, were antiretroviral treatment naive, had routine HIV lab testing at least twice in that year, or tested for syphilis in the preceding year. The proportion with at least one reactive test in 2000-09 was 21.0% (95%CI 19.4, 22.7) for MSM, 5.3% (95%CI 3.3, 7.4) for non-MSM males, and 2.6% (95%CI 1.2, 4.0) for women. Among MSM, the annual prevalence of reactive syphilis tests with high RPR titre (≥1:16) peaked at 3.8% in 2009. CONCLUSIONS: The burden of syphilis co-infection rose considerably among HIV-positive MSM, such that by 2009, at least 1 in 5 men had laboratory evidence of current or past infection. Interventions may be needed to boost syphilis testing to achieve goals set by guidelines even in settings with universal health care.

Systematic review of HIV transmission between heterosexual serodiscordant couples where the HIV-positive partner is fully suppressed on antiretroviral therapy.

BACKGROUND: The risk of sexual HIV transmission in serodiscordant couples when the HIV-positive partner has full virologic suppression on combination antiretroviral therapy (cART) is debated. This study aims to systematically review observational studies and randomized controlled trials (RCTs), evaluating rates of sexual HIV transmission between heterosexual serodiscordant couples when the HIV-positive partner has full suppression on cART. METHODS AND FINDINGS: We searched major bibliographic databases to November 2012 for relevant observational studies and RCTs without language restrictions. Conference proceedings, key journals and bibliographies were also searched. Studies reporting HIV transmission rates, cART histories and viral loads of the HIV-positive partners were included. Two reviewers extracted methodologic characteristics and outcomes. Of 20,252 citations, 3 studies met all eligibility criteria with confirmed full virologic suppression in the HIV-positive partner. We included 3 additional studies (2 cohort studies, 1 RCT) that did not confirm viral suppression in the HIV-positive partner at transmission in a secondary meta-analysis. Methodologic quality was reasonable. The rate of transmission in the 3 studies confirming virologic suppression was 0 per 100 person-years (95% CI = 0-0.05), with low heterogeneity (I(2) = 0%). When we included the 3 studies that did not confirm virologic suppression, the rate of transmission was 0.14 per 100 person-years (95%CI = 0.04-0.31) (I(2) = 0%). In a sensitivity analysis including all 6 studies, the rate of transmission was 0 per 100 person-years (95%CI = 0-0.01) after omitting all transmissions with known detectable or unconfirmed viral loads, as full suppression in these cases was unlikely. Limitations included lack of data on same-sex couples, type of sexual intercourse (vaginal vs. anal), direction of HIV transmission, exact viral load at the time of transmission, sexually transmitted infections (STI) rates, and extent of condom use. CONCLUSIONS: Our findings suggest minimal risk of sexual HIV transmission for heterosexual serodiscordant couples when the HIV-positive partner has full viral suppression on cART with caveats regarding information on sexual intercourse type, STIs, and condom use. These findings have implications when counseling heterosexual serodiscordant couples on sexual and reproductive health. More research is needed to explore HIV transmission risk between same-sex couples.

An Ontario initiative to enhance the effectiveness of AIDS Service Organizations: Community-Linked Evaluation of AIDS Resources.

This report describes the rationale, process, and early outcomes of establishing a community-based research unit. The AIDS Bureau of the Ontario Provincial Government established the Community-Linked Evaluation of AIDS Resources Unit (CLEAR), which works in partnership with the AIDS Bureau and 31 of 74 AIDS Service Organizations (ASOs) in Ontario.