Investigating the spatial association between supervised consumption services and homicide rates in Toronto, Canada, 2010–2023: an ecological analysis

IF 7 Q1 HEALTH CARE SCIENCES & SERVICES Lancet Regional Health-Americas Pub Date : 2025-02-15 DOI:10.1016/j.lana.2025.101022

Dan Werb , Hae Seung Sung , Yingbo Na , Indhu Rammohan , Jolene Eeuwes , Ashley Smoke , Akwasi Owusu-Bempah , Thomas Kerr , Mohammad Karamouzian

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Abstract

Background

Supervised consumption services (SCS) are effective at preventing overdose mortality. However, their effect on public safety remains contested. We investigated homicide rates in areas near SCS in Toronto.

Methods

We classified coroner-reported fatal shootings and stabbings (January 1st, 2010 to September 30th 2023) by geographic zone: within 500 m (‘near’), between 500 m and 3 km (‘far’), and beyond 3 km of an SCS (‘out’). We then used Poisson regression to calculate the rate ratio (RR) across zones 18, 36, 48, and 60 months pre vs. post SCS implementation. Finally, we compared spatial homicide incidence prior to and after the date of the implementation of each SCS using interrupted time series (ITS).

Findings

Overall, 956 homicides occurred, and 590 (62%) were fatal shootings and stabbings. There was no meaningful change in the rate of fatal shootings and stabbings within 3 kms of SCS (near and far zones) after their implementation. However, between 48 and 60 months pos-implementation, we detected an increase in out zones. In an ITS analysis, we observed a reduction in the monthly incidence in near zones and an increase in out zones.

Interpretation

SCS implementation was not associated with increased homicide rates; instead, we observed a reduction in monthly incidence near SCS. These results may inform drug market activity responses that optimize community health and safety.

Funding

Canadian Institutes of Health Research, the New Frontiers in Research Fund, St. Michael’s Hospital Foundation.

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Lancet Regional Health-Americas Multiple-

CiteScore

8.00

自引率

0.00%

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期刊介绍： The Lancet Regional Health – Americas, an open-access journal, contributes to The Lancet's global initiative by focusing on health-care quality and access in the Americas. It aims to advance clinical practice and health policy in the region, promoting better health outcomes. The journal publishes high-quality original research advocating change or shedding light on clinical practice and health policy. It welcomes submissions on various regional health topics, including infectious diseases, non-communicable diseases, child and adolescent health, maternal and reproductive health, emergency care, health policy, and health equity.