Abstract
Background and aims
Syringe‐sharing among people who inject drugs, which can occur during incarceration and post‐release, has been linked with increased risk of blood‐borne infections. We aimed to investigate the cumulative effect of repeated incarceration and the post‐release period on receptive syringe‐sharing.
Design
Ongoing community‐based cohort, recruited through targeted sampling between 2011 and 2012 with 6‐month follow‐ups.
Setting
Tijuana, Mexico.
Participants
Sample of 185 participants (median age 35 years; 67% female) with no history of incarceration at study entry, followed to 2017.
Measurements
Cumulative incarceration and post‐release period were constructed from incarceration events reported in the past 6 months for each study visit. Receptive syringe‐sharing in the past 6 months was assessed as a binary variable. We used logistic regression with generalized estimating equations to examine the association between cumulative incarceration events and the post‐release period with receptive syringe‐sharing over time. Missing data were handled through multiple imputation.
Findings
At baseline, 65% of participants engaged in receptive syringe‐sharing in the prior 6 months. At follow‐up, 150 (81%) participants experienced a total of 358 incarceration events [median = 2, interquartile range (IQR) = 1–3]. The risk of receptive syringe‐sharing increased with the number of repeated incarcerations. Compared with never incarcerated, those with one incarceration had 1.28 [95% confidence interval (CI) = 0.97–1.68] higher adjusted odds of syringe‐sharing; two to three incarcerations, 1.42 (95% CI = 1.02–1.99) and more than three incarcerations, 2.10 (95% CI = 1.15–3.85). Participants released within the past 6 months had 1.53 (95% CI = 1.14–2.05) higher odds of sharing syringes compared with those never incarcerated. This post‐release risk continued up to 1.5 years post‐incarceration (adjusted odds ratio = 1.41, 95% CI = 1.04–1.91), but then waned.
Conclusions
A longitudinal community cohort study among people who inject drugs suggested that the effects of incarceration on increased injecting risk, measured through syringe‐sharing, are cumulative and persist during the post‐release period.