Predictors of Viral Suppression and Rebound Among HIV-Positive Men Who Have Sex With Men in a Large Multi-Site Canadian Cohort
Date
2016
Authors
Tanner, Zachary
Lachowsky, Nathan J.
Ding, Erin
Samji, Hasina
Hull, Mark
Cescon, Angela
Patterson, Sophie
Chia, Jason
Leslie, Alia
Raboud, Janet
Journal Title
Journal ISSN
Volume Title
Publisher
BMC Infectious Diseases
Abstract
Background: Gay, bisexual and other men who have sex with men (MSM) are disproportionately affected by HIV in
Canada. Combination antiretroviral therapy has been shown to dramatically decrease progression to AIDS, premature
death and HIV transmission. However, there are no comprehensive data regarding combination antiretroviral therapy
outcomes among this population. We sought to identify socio-demographic and clinical correlates of viral suppression
and rebound.
Methods: Our analysis included MSM participants in the Canadian Observational Cohort, a multi-site cohort
of HIV-positive adults from Canada's three most populous provinces, aged 2'.18 years who first initiated combination
antiretroviral therapy between 2000 and 2011. We used accelerated failure time models to identify factors
predicting time to suppression (2 measures <50 copies/ml 2'.30 days apart) and subsequent rebound
(2 measures >200 copies/ml 2'.30 days apart).
Results: Of 2,858 participants, 2,448 (86 %) achieved viral suppression in a median time of 5 months (Ql-Q3: 3-7
months). Viral suppression was significantly associated with later calendar year of antiretroviral therapy initiation, no
history of injection drug use, lower baseline viral load, being on an initial regimen consisting of non-nucleoside
reverse-transcriptase inhibitors, and older age. Among those who suppressed, 295 (12 %) experienced viral
rebound. This was associated with earlier calendar year of antiretroviral therapy initiation, injection drug use
history, younger age, higher baseline CD4 cell count, and living in British Columbia.
Conclusions: Further strategies are required to optimize combination antiretroviral therapy outcomes in men who
have sex with men in Canada, specifically targeting younger MSM and those with a history of injection drug use.
Description
We would like to thank all of the participants for allowing their information
to be a part of the CANOC collaboration.
Keywords
Canada, HIV, MSM, Viral load, Suppression, Rebound, Centre for Addictions Research of BC (CARBC), Canadian Institute for Substance Use Research (CISUR)
Citation
Tanner, Z., Lachowsky, N., Ding, E., Samji, H., Hull, M., Cescon, A., Patterson, S., Chia, J., Leslie, A., Raboud, J., Loutfy, M., Cooper, C., Klein, M., Machouf, N., Tsoukas, C., Montaner, J., & Hogg, R. S. for the Canadian Observation Cohort (CANOC) Collaboration. (2016). “Predictors of Viral Suppression and Rebound Among HIV-Positive Men Who Have Sex With Men in a Large Multi-Site Canadian Cohort.” BMC Infectious Diseases, 16(590), 1–11. https://doi.org/10.1186/s12879- 016-1926-z