- An Alberta-funded study examined changes after a Red Deer overdose prevention site closed
- The study looked at opioid agonist therapy dispensing and health service use among clients
- Authors caution the study lacked statistical power to detect significant changes in opioid-related emergency medical services events or mortality
In September 2024, the Government of Alberta announced that they would be closing an overdose prevention site (OPS) in Red Deer. The site closed on March 31, 2025. A study was conducted to examine the impacts of this closure. This study has been cited in policy decisions and debates about closing OPS and supervised consumption services (SCS). However, these findings need to be interpreted with caution because of important limitations outlined in the article that directly affect what conclusions can be drawn from the study.
Study details
The study used a retrospective cohort design to examine what happened after the Red Deer OPS closed, using both within-site and between-site comparisons. Within-site comparisons looked at OPS service users’ outcomes over three phases related to the closure. Between-site comparisons looked at outcomes of people who had used another OPS in Lethbridge.
The study period was broken up into three phases:
- before the announcement of the closure (June 30 to September 28, 2024);
- between the announcement and the closure (September 29, 2024, to March 29, 2025);
- after the closure (March 30 to September 27, 2025).
The study used linked administrative data (using personal health numbers) to examine outcomes among people who had visited the Red Deer OPS at least once. The outcomes the study investigated were weekly dispensing of opioid agonist therapy (OAT) medications, weekly emergency department visits, weekly inpatient hospital admissions, weekly emergency medical services (EMS) events suspected to be related to opioid use, and weekly all-cause mortality.
Data from 381 people who accessed Red Deer OPS and 300 people who accessed Lethbridge OPS, all with valid personal health numbers, were included in the study. Characteristics of these groups of service users were broadly similar, although people who accessed Red Deer’s OPS were slightly older (mean age 38 vs 36 years old) and more likely to be male (59.3% male vs 49.0% male). Both OPS sites collected personal health numbers from a high proportion of clients (97.7% in Red Deer and 94.6% in Lethbridge). However, a small number of service users were not included in this study because they did not have valid personal health numbers; these individuals may have been more marginalized and could have experienced different outcomes after the OPS closure.
There were potentially important differences in the unregulated drug supply, drug use patterns, and services between the two cities. In particular, carfentanil, a highly potent synthetic opioid, was detected in 4% of drug toxicity deaths in Red Deer, compared with 0% in Lethbridge in 2024. In 2025, the percentage of drug toxicity deaths involving carfentanil increased to 36% in Red Deer and to 6% in Lethbridge. These differences may make it difficult to directly compare outcomes between the two communities or attribute changes to the OPS closure.
Study outcomes
The study looked at whether closing the OPS in Red Deer was associated with changes in how many people accessed OAT, interacted with health services (i.e., visiting the emergency department, being hospitalized or having EMS respond to an overdose) or died from any cause. But across all of these outcomes, the findings need to be interpreted with caution because of important limitations outlined in the article that directly affect what conclusions can be drawn from the study.
Opioid agonist therapy (OAT) outcomes
The study found that the number of Red Deer OPS service users dispensed OAT at least once in a week increased gradually in the weeks following the announcement of the closure. After the OPS closed, the number of former service users dispensed OAT at least once in a week went down over time, but it remained higher over the 26-week period after the closure than it was before the announcement.
Before the closure was announced, the proportion of service users dispensed OAT each week was lower in Red Deer (9.9%) than it was in Lethbridge (12.0%). An analysis from the study’s appendices indicates that, between the announcement of the OPS closure and the closure itself, there was no change in the weekly proportion of service users dispensed OAT in Red Deer, compared with in Lethbridge. After the Red Deer site closed, the proportion of former OPS service users receiving OAT in Red Deer rose to 16.1%, slightly higher than in Lethbridge, where it was 14.4% (P < 0.021). Another analysis from the study’s appendices indicates that there was no sustained difference in the trend of OAT dispensing between the two sites after the Red Deer OPS closed.
A limitation of the study’s observational design is that observed changes cannot be attributed to any specific policy, event or activity. This means that the observed increase in OAT dispensing among Red Deer OPS service users cannot be determined to be a result of the closure. The closure of the OPS occurred within Alberta’s provincial health system, which has expanded low-barrier access to OAT through virtual pathways, same-day assessments and broad community-based supports. In addition, interventions implemented in Red Deer, but not Lethbridge, may have impacted OAT dispensing. Specifically, a mobile rapid access addictions medicine clinic was introduced in Red Deer in the lead-up to and after the closure of the OPS, operating in the area immediately surrounding the former OPS. Any of these changes could have contributed to increased OAT dispensing, independently of the OPS site closure.
The authors also note that increased dispensing of OAT after the announcement of the OPS closure may reflect behaviour changes in response to the announcement. For example, the announced closure may have prompted additional outreach or referrals from service providers to encourage people to access OAT. In addition, a few people may have accessed OAT in the absence of an OPS. However, data from the study do not tell us about individual OAT use patterns, such as whether the same people stayed on treatment long-term or if they experienced benefits from it.
The study also cannot determine which factors may explain increased weekly OAT dispensing or establish causation, highlighting the need for caution when interpreting changes in OAT dispensing following shifts in the availability of harm reduction services.
Healthcare and all-cause mortality outcomes
There was a small but significant increase in the weekly number of former Red Deer service users being admitted to the hospital after the Red Deer OPS closed (P = 0.028). After the closure, there was a significantly greater increase over time in weekly hospital admissions among former Red Deer OPS service users than among Lethbridge OPS service users (P = 0.027).
The study did not find any significant changes in weekly emergency department visits, EMS-attended overdoses suspected to be related to opioid use, or all-cause deaths over time, either among Red Deer service users or when compared with Lethbridge service users.
The findings that there were no significant changes in emergency department visits, EMS-attended overdoses suspected to be related to opioid use, or all-cause deaths need to be interpreted with caution because of limitations outlined by the authors. They state that the study lacked statistical power to detect smaller but meaningful changes in these outcomes. This is because of the study’s small sample sizes and the relatively short 26-week follow-up period. To reliably detect changes in these outcomes, the authors estimate that they would have needed to find large differences of about 11% for emergency department visits, 23% for hospital admissions and 96% for EMS-attended overdose events. Smaller increases or decreases, which could still be impactful in real-world settings, may have been missed. In addition, interventions implemented in Red Deer, but not Lethbridge, may have impacted healthcare outcomes. Specifically, an overdose response team was introduced in Red Deer after the closure of the OPS, operating in the area immediately surrounding the former OPS. This intervention may have mitigated health service use following the OPS closure.
Taken together, these findings are inconclusive and should not be interpreted as clear evidence for the safety of shutting down OPS, particularly given an increasingly toxic drug supply.
Resource
Critical Appraisal of “Healthcare utilization and mortality after overdose prevention site closure: A linked cohort analysis using segmented difference-in-differences time series” – Ontario Drug Policy Research Network
REFERENCES
- Day N, Kaufmann K, Devoe D, et al. Healthcare utilization and mortality after overdose prevention site closure: A linked cohort analysis using segmented difference-in-differences time series. Addiction. 2026. https://doi.org/10.1111/add.70380
- Government of Alberta. Province expanding recovery support in Red Deer. September 23, 2024. https://www.alberta.ca/release.cfm?xID=910344608C48C-DC4E-EDBD-2D748EDD0DD4439E
- Hamzat B, Ledlie S, Kolla G, et al. Critical Appraisal of “Healthcare utilization and mortality after overdose prevention site closure: A linked cohort analysis using segmented difference-in-differences time series.” Ontario Drug Policy Research Network. March 2026. https://odprn.ca/wp-content/uploads/2026/03/Critical-Appraisal-Addiction-Study-March-25-2026-1.pdf
- Smith M. Alberta government to close Red Deer overdose prevention site, add new recovery services. CBC News. September 24, 2024. https://www.cbc.ca/news/canada/edmonton/alberta-government-to-close-red-deer-overdose-prevention-site-add-new-recovery-services-1.7333122