Gender-specific associations between psychological distress and injecting risk behaviours among people who inject drugs in Montreal, Canada

Abstract

Background: Psychological distress is common among people who inject drugs (PWID) and may be associated with HCV-related risk behaviours. Previous studies have documented increased vulnerability to both psychological distress and HCV infection among female relative to male PWID. It is, however, unclear whether behavioural responses to distress differ by gender. This study estimated gender-specific associations between psychological distress and i) binge drug injection, and ii) sharing of injection materials.

Methods: Data were drawn from HEPCO, a longitudinal cohort study involving three-monthly interviews with active PWID in Montreal, Canada. Past-month psychological distress was assessed with the Kessler (K10) scale, categorized for descriptive analyses as minimal (score 10-15), moderate (16-21), high (22-29), or severe (30-50). Binge was defined as injecting large quantities of drugs until participants could no longer continue (past 3 months). Sharing was defined as injection with previously-used needles or equipment (past 3 months). Generalized additive models were fit to estimate smooth, nonlinear associations between K10 scores and risk behaviours, by gender. Models were adjusted for known determinants of drug-related harms and included random intercepts to model within-subject correlation.

Results: 805 individuals (82% male) provided 8158 observations (2011-2020). High to severe levels of distress were common and more frequent among women (55% vs 37%). Among men, the odds of binge and sharing monotonically and non-linearly increased with increasing scores of psychological distress. Associations for binge among women were attenuated relative to men but nevertheless increased with distress, albeit in a linear fashion. Sharing was not associated with distress among women.

Conclusion: Psychological distress was differentially associated with injecting risk behaviours among men and women who inject drugs. Assessment of distress may provide novel prevention opportunities for select PWID. Further investigation into gender differences is warranted to inform development and tailoring of interventions.

Keywords: Binge; Gender; Mental health; PWID; Psychological distress; Sharing.