ArticleBMJ public health2023
What impact did the COVID-19 pandemic have on the variability of fentanyl concentrations in the Vancouver, Canada illicit drug supply? An interrupted time-series analysis.
Article in BMJ public health, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 10 papers.
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Who cites it
10 citing papers in PubMed.
- Temporal and regional associations between fentanyl concentrations in the unregulated drug supply and drug-related mortality in British Columbia, Canada.The International journal on drug policy · 2026Article
- How population-level drug supply data are integrated into health outcomes research: a scoping review.Epidemiologic reviews · 2026Article
- Trends of incident stimulant use disorder diagnoses before and after the COVID-19 pandemic in British Columbia (2013-2024): a population-based study.Frontiers in psychiatry · 2026Article
- Impact of having a regular drug dealer on obtaining drug checking results consistent with expectations during a drug toxicity crisis in a Canadian setting.Drug and alcohol dependence · 2025Article
- Opioid-related deaths in Northern Ontario in the early COVID-19 pandemic period.Canadian journal of public health = Revue canadienne de sante publique · 2025Article
- 'It just doesn't stop': Perspectives of women who use drugs on increased overdoses during the COVID-19 pandemic.Drug and alcohol review · 2025Article
- Impacts of the COVID-19 pandemic on supervised consumption service delivery in Vancouver and Surrey, Canada from the perspective of service providers.Discover public health · 2025Article
- Impacts of the COVID-19 pandemic on the availability and retail price of unregulated drugs in Vancouver, Canada: An interrupted time-series analysis, 2018-2022.The International journal on drug policy · 2024Article
- Local Impact From International Crises: Unregulated Drug Toxicity During the COVID-19 Pandemic in British Columbia, Canada.American journal of public health · 2024Article
- Volatile drug use and overdose during the first year of the COVID-19 pandemic in the United States.The International journal on drug policy · 2024Article
Corrections and comments
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Authors and funding
8 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Background: Increases in fatal overdoses were observed coinciding with the COVID-19 pandemic across the USA and Canada. Hypothesised explanations include pandemic-attributable healthcare service disruption, social isolation and illicit drug market disruption. Using data from a community drug checking service, this study sought to evaluate how COVID-19 pandemic measures affected the variability in fentanyl concentrations within the local illicit drug market. Methods: Using a validated quantification model for fentanyl, Fourier-transform infrared spectra from fentanyl-positive drug checking samples in Vancouver, Canada were analysed to determine fentanyl concentration. An interrupted time-series analysis using an ordinary least squares model with autoregressive adjusted SEs was conducted to measure how the variance in monthly fentanyl concentrations changed following the declaration of the COVID-19 public health emergency in March 2020. Results: Over the study period, 4713 fentanyl-positive samples were available for analysis. Monthly variance of fentanyl concentrations ranged from 7.9% in December 2017 to 159.2% in September 2020. An interrupted time-series analysis of variance in fentanyl concentrations increased significantly following the declaration of the COVID-19 public health emergency, with an immediate level change of 26.1 (95% CI 7.2 to 45.0, p=0.011) and a slope change of 15.8 (95% CI 10.2 to 21.4, p<0.001). Conclusion: Though community drug checking samples may not be generalisable to the wider illicit drug market, our study found that variance in fentanyl concentrations increased significantly following the declaration of the COVID-19 public health emergency. While it remains unclear whether the observed increase in the variability of fentanyl concentration in illicit opioids was a direct result of COVID-19 and related measures, the volatility of fentanyl concentrations is likely to have posed significant risk to people who used drugs in this setting.
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