Jane A. Buxton

Fentanyl toxicity is the leading cause of unnatural death in British Columbia (BC), Canada, driven in part by fentanyl’s potency and unpredictable, highly variable concentration in unregulated drug samples. This study aims to identify emerging trends and the possible relationship between fentanyl concentrations in community drug samples and the postmortem blood of drug-toxicity decedents. Data for this ecological study were derived from Vancouver, BC community drug-checking sites and the BC Coroners Service. We analyzed fentanyl concentrations of opioid drug-checking samples alongside postmortem blood fentanyl concentrations from unintentional drug-toxicity decedents in which fentanyl contributed. The study period was January 2018 through December 2022. Monthly median fentanyl concentrations of drug-checking samples were compared to postmortem blood concentrations using generalized additive models. The primary time-series model, adjusted for potential confounders, did not identify a statistically significant association between drug-checking and postmortem concentrations (edf = 3.58, χ2 = 8.48, P = 0.104); however, a sensitivity analysis excluding extreme values revealed a significant nonlinear association (edf = 3.91, χ2 = 11.71, P = 0.038). Fentanyl concentrations in both the unregulated drug supply and postmortem blood changed over time with the two being mutually associated: as median fentanyl concentrations in opioid drug-checking samples increased, postmortem blood fentanyl concentrations generally decreased. Further research into complexities of the drug supply, changing substance use patterns, and rates of fentanyl exposure among opioid-naïve individuals may explain this nonlinear trend and inform strategies to abate the ongoing crisis.

Objective: In recent years, Canada’s unregulated drug supply has become permeated by novel adulterants (e.g., fentanyl analogues, benzodiazepines, xylazine). While fentanyl has been shown to be associated with overdose mortality and other non-fatal health outcomes, adverse events (AE) associated with these adulterants remain poorly described. This study seeks to identify whether common adulterants identified through drug checking services are associated with increased prevalence of specific adverse events reportedly experienced by people who use drugs. Methods: Drug checking samples were analyzed using Fourier-transform infrared spectroscopy and immunoassay strips at harm reduction sites in British Columbia. Self-reported AE (e.g., non-fatal overdose, prolonged sedation, seizures) were recorded from individuals who checked opioids post-consumption. Adjusted prevalence ratios (aPR) and 95% confidence intervals (95% CI) of AE among common adulterants were calculated using generalized linear models with a Poisson distribution, controlled for presence of other adulterants, expected drug, geographic location, and month. Results: Between February 2022 and May 2024, 80,415 samples were analyzed at community sites. Among eligible samples, 36.1% were expected opioids, 42.2% of which were checked post-consumption. AE were noted among 10.7% of post-consumption opioid drug checks. After adjustment, the presence of benzodiazepines in opioid samples was associated with increased prevalence of any AE (aPR 1.97; 95% CI 1.70–2.27), as was the presence of xylazine (aPR 1.50; 95% CI 1.09–2.07). Considering specific AE, benzodiazepines were associated with increased prevalence of overdose (aPR 2.05; 95% CI 1.68–2.51) and prolonged sedation (aPR 3.35; 95% CI 2.54–4.43). Conclusion: Non-fatal AE associated with unregulated opioids have been largely undescribed. Our findings report specific AE associated with different adulterants in the unregulated opioid supply. With this information, tailored public health interventions and services focused on these adulterants can be developed.

Objectives: This study evaluates the prevalence and correlates of opioid agonist therapy (OAT) discontinuation across British Columbia (BC), using a sample of individuals who used substances and accessed harm reduction sites. Design: This study uses data from the 2019 cross-sectional Harm Reduction Client Survey (HRCS). Setting: The 2019 survey was administered from October to December at 22 harm reduction supply distribution sites across the 5 Regional Health Authorities of BC. Participants: The 2019 HRCS was administered among individuals who used illicit substances in the past 6 months and were aged 19 years and above. Primary and secondary outcome measures: The primary outcome was defined as self-reported discontinuation of OAT in the past 6 months. Measures of association (χ ² and Fisher’s exact tests) and logistic regression models were used to assess the strength of association between OAT discontinuation and demographic, socioeconomic, accessibility, drug use and harm reduction correlates. Results: Of the 194 participants included, 59.8% self-identified as cis man, 37.6% self-identified as Indigenous, 38.1% were aged 30–39 years and 43.8% had discontinued OAT in the past 6 months. Multivariable logistic regression analyses identified that those aged ≥50 years (AOR=0.12, 95% CI (0.03 to 0.45)) and those who took the survey in medium/large urban areas (AOR=0.27, 95% CI (0.07 to 0.98)) were significantly less likely to discontinue OAT, while those who experienced an overdose in the past 6 months were significantly more likely (AOR=3.77, 95% CI (1.57 to 9.03)) to have discontinued OAT in the past 6 months. Substance use, including opioids and stimulants, was similar among those who continued and discontinued OAT. Of the 73 participants who discontinued OAT and provided a reason, one-third reported discontinuing OAT because treatment was not effective, 27.4% could not get to the pharmacy during open hours, 23.3% could not make their clinic appointment and 15.1% reported challenges with transportation/travel. Conclusions: OAT discontinuation prevention efforts for individuals using substances in BC need to address disparities in healthcare accessibility, especially in rural areas and among younger individuals. Continued access to harm reduction services can allow for safer consumption of substances for individuals enrolled in OAT programs.

Objectives To summarise PEEP’s (Professionals for Ethical Engagement of Peers—a group of consultants with lived and living experience of substance use) outputs and gain insights into PEEP’s impact and suggestions for the future. Design Included an environmental scan to collate PEEP activities and outputs and a participatory qualitative design using thematic analysis. Setting British Columbia, Canada. Participants Eight members of PEEP and nine staff/people who consulted PEEP were interviewed. Results PEEP members are co-authors/acknowledged for their input in 25 peer review publications and 16 reports; PEEP members co-presented or were co-authors on 33 presentations. PEEP meets by Zoom two times per week and is paid monthly via honorarium from the Provincial Health Service Authority at a current rate of $C30 per hour. Four themes emerged from our interviews: (1) What is PEEP? (PEEP provides a sense of community, holds systems accountable and inspires others), (2) PEEP Process (suggestions for improvement: consultants should be prepared and involve PEEP throughout the process and report how PEEP’s insights were used), (3) PEEP Outcomes (PEEP members gain skills and confidence, PEEP provides a reality check, consultants learn from PEEP, and input leads to practice changes) and (4) Future of PEEP (sustainable funding and opportunities for growth are critical). Conclusion PEEP is a cohesive group whose input is well-respected and influences policy and programmes. Given the ongoing drug toxicity emergency, it is critical to continue to support and expand PEEP.

The current evidence regarding effective management of methamphetamine and amphetamine (MA/A) use disorders is inconclusive. Therefore, we assessed the comparative benefits and tolerability of pharmacological, psychosocial, and harm reduction interventions for management of MA/A use disorders. We searched six electronic databases for randomized controlled trials of any pharmacological, psychosocial, or harm reduction interventions in adults with MA/A use disorders. We performed a random-effects frequentist network meta-analysis and used the GRADE approach to assess the certainty of evidence. We included 72 randomized trials (6836 participants). Low certainty evidence suggests quetiapine may extend abstinence compared to placebo [risk ratio (RR) 3.17 (95% confidence intervals (CI), 1.24 to 8.07)] and weekly average proportion of patients with negative urine samples [mean difference (MD) 32.17 (95% CI, 14.08 to 50.26)]. Low certainty evidence also suggested that riluzole may be associated with a higher weekly average proportion of patients with negative urine samples [MD 24.10 (95% CI, 5.54 to 42.66)]. Very low certainty evidence suggests methylphenidate alone [compared to placebo MD 10.24 (95% CI, 3.49 to 16.99)] or in combination with matrix model [MD 23.55 (95% CI, 7.64 to 39.46)] may be associated with an increased weekly average proportion of patients with negative urine samples. Compared to placebo, contingency management alone [MD 21.20 (95% CI, 11.39 to 31.00), very low certainty] or in combination with cognitive behavioural therapy [MD 34.85 (95% CI, 19.63 to 50.08), very low certainty] may be associated with longer duration of abstinence. Compared to placebo, venlafaxine [RR 0.27 (95% CI 0.08 to 0.90), low certainty] and citicoline [RR 0.69 (95% CI 0.49 to 0.99), lowcertainty] may be among the most tolerable interventions. Very few interventions may be associated with slight improvement in certain outcomes, but no intervention showed moderate- to high-certainty evidence for important changes across any patient-important outcomes.