Cohort Profile: The Ontario HIV Treatment Network Cohort Study (OCS)

Abstract

The Ontario HIV Treatment Network Cohort Study (OCS) is an observational, open dynamic cohort of people who are receiving medical care for human immunodeficiency virus (HIV) infection in Ontario, Canada. Established in the mid-1990s, the OCS has its roots in AIDS activists' demands for research that would improve the quality of life of people living with HIV while respecting their privacy. It is a collaborative and community-driven study, including a Governance Committee made up of people with HIV and other stakeholders that evaluates analysis project proposals for community relevance and ethics. From 1995 to 2010, a total of 5644 participants were enrolled and 27,720 person-years of observation were accumulated; follow-up will continue until at least 2015. In the initial years of study, the focus was on clinical data from medical chart reviews. It has since evolved into a comprehensive study that collects extensive de-identified information on clinical, laboratory and psychosocial and behavioural measures based on medical chart abstractions, interviews using a standardized questionnaire and linkage with external administrative health databases in Ontario. Interested collaborators are encouraged to submit analysis project proposals as instructed on the study website (www.ohtncohortstudy.ca).

Prevalence, Recurrence, and Incidence of Current Depressive Symptoms among People Living with HIV in Ontario, Canada: Results from the Ontario HIV Treatment Network Cohort Study

“…Our results from a longitudinal perspective strengthen the current knowledge that poorer housing and neighbourhood conditions may worsen depressive symptoms in people living with HIV in the long run. In North America, people living with HIV are struggling with poverty and unstable housing situations [23,43]. These results also reinforce the importance of providing stable and good quality neighbourhood conditions in current HIV policy and programs, which may help alleviate depressive symptoms and improve the overall well-being of people living with HIV over time.…”

“…The OCS is a multi-site HIV cohort, described in detail in a previous publication [43]. HIV-positive participants who received care were recruited from HIV specialty care clinics in Ontario.…”

“…HIV-positive participants who received care were recruited from HIV specialty care clinics in Ontario. Clinical nurses and assistants interviewed the HIV-positive participants during regular clinical appointments [43]. The OCS data source contains participants’ medical records from chart abstractions, HIV viral load/HIV antigen test records provided by Public Health Ontario Laboratories, socio-demographics, and psychosocial and behavioural data [43].…”

“…Clinical nurses and assistants interviewed the HIV-positive participants during regular clinical appointments [43]. The OCS data source contains participants’ medical records from chart abstractions, HIV viral load/HIV antigen test records provided by Public Health Ontario Laboratories, socio-demographics, and psychosocial and behavioural data [43]. The frequency of follow-up for each HIV-positive participant depended on the frequency of his/her clinical appointments.…”

Cost-Effectiveness of Enhanced Syphilis Screening among HIV-Positive Men Who Have Sex with Men: A Microsimulation Model

“…We synthesized health and economic data related to syphilis in HIV-positive MSM; probability, cost, and quality-of-life estimates were derived from the published literature wherever possible and are presented in Table 1 . The model was used to simulate 500,000 individual men similar to those enrolled in the Ontario HIV Treatment Network Cohort Study (OCS), an observational, open dynamic cohort of people receiving medical care for HIV infection in Ontario, Canada [21]. OCS data were used to estimate the proportion of men in the cohort with previous treated infection [10].…”