Rising mortality among people who inject drugs living with HIV in Scotland, UK: A 20-year retrospective cohort study.

Objectives: Our aim was to examine mortality trends in the era of antiretroviral therapy, among people who inject drugs (PWID) who are living with HIV. The study objectives were to assess and quantify mortality among PWID diagnosed with HIV over time in Scotland, in the context of a recent outbreak of HIV and rise in drug-related mortality.

Methods: This was a retrospective cohort study of those diagnosed with HIV in Scotland between January 2000 and February 2020, with acquisition related to injecting drug use, linked to mortality data. Factors associated with all-cause mortality were examined using Cox proportional hazards regression.

Results: Among 430 individuals with 3143 person-years (py) of follow-up, 88 (20.5%) died. Drug-related deaths accounted for 45.5% of all deaths, rising to 60% among those diagnosed in 2015-2020. The crude all-cause mortality was 28.00 per 1000 py overall and 37.62 per 1000 py within 5 years of diagnosis. Mortality risk was markedly higher among PWID diagnosed in 2015-2020 [adjusted hazard ratio (aHR) = 3.53], relative to those diagnosed in 2000-2004. Among those diagnosed in 2015-2020 (as part of the HIV outbreak), the mortality risk was higher among those not on, compared with those on, opioid agonist therapy (aHR = 3.87).

Conclusion: Mortality among PWID living with HIV in Scotland has risen substantially in the 21st century. Our findings highlight the important role of opioid-agonist therapy, alongside other prevention and treatment measures to address high levels of drug-related mortality for PWID living with HIV, including within HIV outbreaks in this population group.