Behavioural, social and structural-level risk factors for developing AIDS among HIV-positive people who use injection drugs in a Canadian setting, 1996–2017

ABSTRACT

People who use injection drugs (PWID) experience high rates of HIV acquisition and, as a result of lower rates of optimal access and adherence to combination antiretroviral therapy (ART), experience worse HIV treatment outcomes than other key affected populations. However, the incidence and risk factors for the development of AIDS among HIV-positive PWID have not been completely described. We used data from a community-recruited prospective cohort of HIV-positive PWID in Vancouver, Canada, a setting with universal no-cost ART and a comprehensive clinical monitoring registry. We used multivariable extended Cox models to identify factors associated with time to AIDS. Between 1996 and 2017, 396 participants, including 140 (35.4%) women, were followed for a median of 39.0 months (interquartile range: 16.6–76.2), among whom 165 (41.7%) developed AIDS. In a multivariable model, homelessness (Adjusted Hazard Ratio [AHR] = 1.76 (1.18–2.61)) and injection drug use within the preceding six months (AHR = 1.74 (1.17–2.58)) were independently associated with a higher risk of developing AIDS. Despite widespread scale-up of programmes to improve ART utilization, significant risk factors for the development of AIDS remain among HIV-positive PWID in this setting.

KEYWORDS:

• HIV infections
• AIDS
• treatment outcome
• antiretroviral therapy
• substance abuse

Acknowedgments

The authors thank the study participants for their contribution to the research, as well as current and past researchers and staff.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The study was supported by the US National Institutes of Health [grant numbers U01DA021525, R25-DA037756]. MJM is supported by theNational Institute on Drug Abuse [grant number U01-DA021525], a Canadian Institutes of Health Research New Investigator award and a Michael Smith Foundation for Health Research (MSFHR) Scholar Award. His institution has received an unstructured gift from NG Biomed Ltd., a private firm applying to the Canadian federal government for a licence to produce medical cannabis to support him. LT is supported by a MSFHR Scholar Award. NF is supported by MSFHR and St. Paul’s Foundation Scholar awards.