The prevalence of HIV pre-exposure prophylaxis (HIV-PrEP) use and HIV-PrEP-to-need ratio in nine Canadian provinces, 2018-2021.

Background: Measuring trends in HIV pre-exposure prophylaxis (HIV-PrEP) uptake is important to inform planning for prevention programs and policies. The HIV-PrEP-to-need ratio (PnR) is a construct used by public health organizations to explore disparities in the provision of HIV-PrEP across geographic areas and demographic categories (e.g.

Secondary use of routinely collected administrative health data for epidemiologic research: Answering research questions using data collected for a different purpose.

The use of routinely collected administrative health data for research can provide unique insights to inform decision-making and, ultimately, support better public health outcomes. Yet, since these data are primarily collected to administer healthcare service delivery, challenges exist when using such data for secondary purposes, namely epidemiologic research. Many of these challenges stem from the researcher's lack of control over the quality and consistency of data collection, and - furthermore - a lessened understanding of the data being analyzed.

Retention in primary care among unstably housed residents of a low-income, inner-city neighborhood with a high prevalence of substance use and related disorders.

Introduction: Access to and engagement with primary healthcare can be difficult for marginalized low-income populations residing in inner cities in high-income countries. We designed a study to examine retention in primary care among clients of a novel interdisciplinary primary care clinic in the Downtown Eastside of Vancouver, Canada who did not previously have access to care.

Methods: Beginning in June 2021, clients of the Hope to Health clinic were offered enrolment in a cohort study which involved a baseline and follow-up surveys every six months, and linking their data to information from the clinic's electronic medical records.

Access to care and impact on HIV treatment interruptions during the COVID-19 pandemic among people living with HIV in British Columbia.

Introduction: The COVID-19 pandemic has changed healthcare service delivery. We examined the overall impact of COVID-19 on people living with HIV in British Columbia (BC), Canada, with a special focus on the potential impact of COVID-19 on antiretroviral treatment interruptions (TIs).

Methods: Purposive sampling was used to enrol people living with HIV aged ≥19 years across BC into the STOP HIV/AIDS Program Evaluation study between January 2016 and September 2018.

The impact of the COVID-19 pandemic on HIV treatment gap lengths and viremia among people living with HIV British Columbia, Canada, during the COVID-19 pandemic: Are we ready for the next pandemic?

The SARS-CoV-2 (COVID-19) pandemic has impacted the care of people living with HIV (PLWH). This study aims to characterize the impact of the pandemic on the length of HIV treatment gap lengths and viral loads among people living with HIV (PLWH) in British Columbia (BC), Canada, with a focus on Downtown Eastside (DTES), which is one of the most impoverished neighbourhoods in Canada. We analyzed data from the HIV/AIDS Drug Treatment Program from January 2019 to February 2022.

Adverse drug reactions attributed to generic substitution of antiretroviral medications among HIV treatment and pre-exposure prophylaxis clients in British Columbia, Canada.

Background: In British Columbia, antiretrovirals (ARVs) for HIV treatment (HIV-Tx) and pre-exposure prophylaxis (PrEP) are free-of-charge through publicly-funded Drug Treatment Programs (DTPs). When available, less costly generics are substituted for brand-name ARVs. We describe the incidence and type of product substitution issue (PSI) adverse drug reactions (ADRs) attributed to generic ARVs.

Effects of COVID-19 mRNA vaccination on HIV viremia and reservoir size.

Objective: The immunogenic nature of coronavirus disease 2019 (COVID-19) mRNA vaccines led to some initial concern that these could stimulate the HIV reservoir. We analyzed changes in plasma HIV loads (pVL) and reservoir size following COVID-19 mRNA vaccination in 62 people with HIV (PWH) receiving antiretroviral therapy (ART), and analyzed province-wide trends in pVL before and after the mass vaccination campaign.

Design: Longitudinal observational cohort and province-wide analysis.

Risk of Multiple Sclerosis in People Living with HIV: An International Cohort Study.

Objective: There has been interest in a possible negative association between HIV and multiple sclerosis (MS). We aimed to compare the risk of MS in a cohort of individuals living with HIV to that in the general population.

Methods: Population-based health data were accessed for 2 cohorts of HIV-positive persons from Sweden and British Columbia, Canada.

Effects of COVID-19 mRNA vaccination on HIV viremia and reservoir size.

Objective: The immunogenic nature of COVID-19 mRNA vaccines led to some initial concern that these could stimulate the HIV reservoir. We analyzed changes in plasma HIV loads (pVL) and reservoir size following COVID-19 mRNA vaccination in 62 people with HIV (PWH) receiving antiretroviral therapy (ART), and analyzed province-wide trends in pVL before and after the mass vaccination campaign.

Design: Longitudinal observational cohort and province-wide analysis.

Identification of people with low prevalence diseases in administrative healthcare records: A case study of HIV in British Columbia, Canada.

Introduction: Case-finding algorithms can be applied to administrative healthcare records to identify people with diseases, including people with HIV (PWH). When supplementing an existing registry of a low prevalence disease, near-perfect specificity helps minimize impacts of adding in algorithm-identified false positive cases. We evaluated the performance of algorithms applied to healthcare records to supplement an HIV registry in British Columbia (BC), Canada.

Depressive Symptoms, the Impact on ART Continuation, and Factors Associated with Symptom Improvement Among a Cohort of People Living with HIV in British Columbia, Canada.

Depressive symptoms among people living with HIV (PLWH) are associated with poorer overall health outcomes. We characterized depressive symptoms and improvements in symptomology among PLWH (≥ 19 years old) in British Columbia (BC), Canada. We also examined associations between depressive symptomology and antiretroviral therapy (ART) treatment interruptions.

Process description of developing HIV prevention monitoring indicators for a province-wide pre-exposure prophylaxis (PrEP) program in British Columbia, Canada.

In 2018, the pre-exposure prophylaxis (PrEP) program was initiated in British Columbia (BC), Canada, providing PrEP at no cost to qualifying residents. This observational study discussed the steps to develop key evidence-based monitoring indicators and their calculation using real-time data. The indicators were conceptualized, developed, assessed and approved by the Technical Monitoring Committee of representatives from five health authority regions in BC, the BC Ministry of Health, the BC Centre for Disease Control, and the BC Centre for Excellence in HIV/AIDS.

Antibody response durability following three-dose coronavirus disease 2019 vaccination in people with HIV receiving suppressive antiretroviral therapy.

Background: Limited data exist regarding longer term antibody responses following three-dose coronavirus disease 2019 (COVID-19) vaccination, and the impact of a first SARS-CoV-2 infection during this time, in people with HIV (PWH) receiving suppressive antiretroviral therapy (ART). We quantified wild-type-specific, Omicron BA.1-specific and Omicron BA.

Virological suppression among gay, bisexual, and other men who have sex with men living with HIV in Vancouver, Canada: A longitudinal cohort study from 2012-2017.

Introduction: In 2010, British Columbia (BC) implemented HIV Treatment as Prevention (TasP) as policy. We examined trends in virologic suppression and determinants of significant viremia among a prospective biobehavioural cohort of men who have sex with men (gbMSM) in Vancouver from 2012-2017.

Methods: Respondent-driven sampling was used to recruit sexually active gbMSM (≥16 years) who completed biannual study visits with a computer-assisted self-interview and clinical CD4 and viral load (VL) testing.

People With Human Immunodeficiency Virus Receiving Suppressive Antiretroviral Therapy Show Typical Antibody Durability After Dual Coronavirus Disease 2019 Vaccination and Strong Third Dose Responses.

Background: Longer-term humoral responses to 2-dose coronavirus disease 2019 (COVID-19) vaccines remain incompletely characterized in people living with human immunodeficiency virus (HIV) (PLWH), as do initial responses to a third dose.

Methods: We measured antibodies against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein receptor-binding domain, angiotensin-converting enzyme 2 (ACE2) displacement, and viral neutralization against wild-type and Omicron strains up to 6 months after 2-dose vaccination, and 1 month after the third dose, in 99 PLWH receiving suppressive antiretroviral therapy and 152 controls.

Results: Although humoral responses naturally decline after 2-dose vaccination, we found no evidence of lower antibody concentrations or faster rates of antibody decline in PLWH compared with controls after accounting for sociodemographic, health, and vaccine-related factors.

Evolving patterns of antiretroviral drug interactions in people with HIV in British Columbia, Canada.

Objectives: To characterize the annual prevalence of antiretroviral/nonantiretroviral drug interactions in relation to antiretroviral therapy (ART)-prescribing patterns, and to describe drug interaction-related ART changes.

Design/methods: This cohort study included ART-treated adults in British Columbia, Canada between 01 January 2010 and 31 December 2016. Medication dispensing records were abstracted from a population-based, linked administrative-health dataset and used to identify antiretroviral-comedication drug interactions ('caution'/'avoid' drug interactions in HIV-focused drug interaction checkers).

Prevalence and incidence of hepatitis C infection amongst men who have sex with men in a population-based pre-exposure prophylaxis program in British Columbia, Canada.

Background: Men who have sex with men (MSM) are at risk for sexually-transmitted hepatitis C (HCV). Evidence for HCV infection in the context of pre-exposure prophylaxis (PrEP) use in North America is limited. We sought to characterize baseline HCV prevalence and incidence in MSM receiving PrEP in British Columbia (BC), Canada.

Humoral immune responses to COVID-19 vaccination in people living with HIV receiving suppressive antiretroviral therapy.

Humoral responses to COVID-19 vaccines in people living with HIV (PLWH) remain incompletely characterized. We measured circulating antibodies against the SARS-CoV-2 spike protein receptor-binding domain (RBD), ACE2 displacement and viral neutralization activities one month following the first and second COVID-19 vaccine doses, and again 3 months following the second dose, in 100 adult PLWH and 152 controls. All PLWH were receiving suppressive antiretroviral therapy, with median CD4+ T-cell counts of 710 (IQR 525-935) cells/mm, though nadir CD4+ T-cell counts ranged as low as <10 cells/mm.

The impact of lookback windows on the prevalence and incidence of chronic diseases among people living with HIV: an exploration in administrative health data in Canada.

Background: We described the impact of different lengths of lookback window (LW), a retrospective time period to observe diagnoses in administrative data, on the prevalence and incidence of eight chronic diseases.

Methods: Our study populations included people living with HIV (N = 5151) and 1:5 age-sex-matched HIV-negative individuals (N = 25,755) in British Columbia, Canada, with complete follow-up between 1996 and 2012. We measured period prevalence and incidence of diseases in 2012 using LWs ranging from 1 to 16 years.

Chronic Hepatitis B Infection Among Preexposure Prophylaxis Users Enrolled in a Population-Based Program in British Columbia, Canada.

Initiation of human immunodeficiency virus preexposure prophylaxis (PrEP) medications will also treat hepatitis B infection (HBV). The prevalence of chronic HBV was 0.86% (n=41/4760) among enrollees in a provincial PrEP program in British Columbia, Canada.

Concordance of HIV transmission risk factors elucidated using viral diversification rate and phylogenetic clustering.

Background And Objectives: Although HIV sequence clustering is routinely used to identify subpopulations experiencing elevated transmission, it over-simplifies transmission dynamics and is sensitive to methodology. Complementarily, viral diversification rates can be used to approximate historical transmission rates. Here, we investigated the concordance and sensitivity of HIV transmission risk factors identified by phylogenetic clustering, viral diversification rate, changes in viral diversification rate and a combined approach.

Humoral immune responses to COVID-19 vaccination in people living with HIV receiving suppressive antiretroviral therapy.

Humoral responses to COVID-19 vaccines in people living with HIV (PLWH) remain incompletely understood. We measured circulating antibodies against the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein, ACE2 displacement and live viral neutralization activities one month following the first and second COVID-19 vaccine doses in 100 adult PLWH and 152 controls. All PLWH were receiving suppressive antiretroviral therapy, with median CD4+ T-cell counts of 710 (IQR 525-935) cells/mm .

Clinical and demographic predictors of antiretroviral efficacy in HIV-HBV co-infected patients.

Background: The clinical and demographic characteristics that predict antiretroviral efficacy among patients co-infected with HIV and hepatitis B virus (HBV) remain poorly defined. We evaluated HIV virological suppression and rebound in a cohort of HIV-HBV co-infected patients initiated on antiretroviral therapy.

Methods: A retrospective cohort analysis was performed with Canadian Observation Cohort Collaboration data.