Estimated Drug Overdose Deaths Averted by North America’s First Medically-Supervised Safer Injection Facility M-J. S. Milloy1,2, Thomas Kerr1,3, Mark Tyndall1,3, Julio Montaner1,3, Evan Wood1,3* 1 British Columbia Centre for Excellence in HIV/AIDS, St. Paul’s Hospital, Vancouver, Canada, 2 School of Population and Public Health, University of British Columbia, Vancouver, Canada, 3 Department of Medicine, University of British Columbia, Vancouver, Canada Abstract Background: Illicit drug overdose remains a leading cause of premature mortality in urban settings worldwide. We sought to estimate the number of deaths potentially averted by the implementation of a medically supervised safer injection facility (SIF) in Vancouver, Canada. Methodology/Principal Findings: The number of potentially averted deaths was calculated using an estimate of the local ratio of non-fatal to fatal overdoses. Inputs were derived from counts of overdose deaths by the British Columbia Vital Statistics Agency and non-fatal overdose rates from published estimates. Potentially-fatal overdoses were defined as events within the SIF that required the provision of naloxone, a 911 call or an ambulance. Point estimates and 95% Confidence Intervals (95% CI) were calculated using a Monte Carlo simulation. Between March 1, 2004 and July 1, 2008 there were 1004 overdose events in the SIF of which 453 events matched our definition of potentially fatal. In 2004, 2005 and 2006 there were 32, 37 and 38 drug-induced deaths in the SIF’s neighbourhood. Owing to the wide range of non-fatal overdose rates reported in the literature (between 5% and 30% per year) we performed sensitivity analyses using non-fatal overdose rates of 50, 200 and 300 per 1,000 person years. Using these model inputs, the number of averted deaths were, respectively: 50.9 (95% CI: 23.6–78.1); 12.6 (95% CI: 9.6–15.7); 8.4 (95% CI: 6.5–10.4) during the study period, equal to 1.9 to 11.7 averted deaths per annum. Conclusions/Significance: Based on a conservative estimate of the local ratio of non-fatal to fatal overdoses, the potentially fatal overdoses in the SIF during the study period could have resulted in between 8 and 51 deaths had they occurred outside the facility, or from 6% to 37% of the total overdose mortality burden in the neighborhood during the study period. These data should inform the ongoing debates over the future of the pilot project. Citation: Milloy MJS, Kerr T, Tyndall M, Montaner J, Wood E (2008) Estimated Drug Overdose Deaths Averted by North America’s First Medically-Supervised Safer Injection Facility. PLoS ONE 3(10): e3351. doi:10.1371/journal.pone.0003351 Editor: Atle Fretheim, Norwegian Knowledge Centre for the Health Services, Norway Received May 23, 2008; Accepted September 15, 2008; Published October 7, 2008 Copyright: 2008 Milloy et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: The SIF evaluation was originally funded by a contribution from Health Canada, although the views expressed in this analysis do not represent the official policies of Health Canada. The evaluation is now supported by the Canadian Institutes of Health Research and Vancouver Coastal Health. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: Evan Wood, Thomas Kerr and M-J Milloy declare that there is no competing interest that they should disclose. Julio Montaner has received educational grants from, served as an ad hoc adviser to or spoken at various events sponsored by Abbott Laboratories, Agouron Pharmaceuticals Inc., Boehringer Ingelheim Pharmaceuticals Inc., Borean Pharma AS, Bristol-Myers Squibb, DuPont Pharma, Gilead Sciences, GlaxoSmithKline, Hoffmann-La Roche, Immune Response Corporation, Incyte, Janssen-Ortho Inc., Kucera Pharmaceutical Company, Merck Frosst Laboratories, Pfizer Canada Inc., Sanofi Pasteur, Shire Biochem Inc., Tibotec Pharmaceuticals Ltd. and Trimeris Inc. Mark Tyndall has received research grants from and served as an ad hoc adviser to Tibotec (J&J), BMS and Gilead Sciences. * E-mail: uhri-ew@cfenet.ubc.ca Introduction Illicit drug overdose remains a leading cause of death and disability in many urban settings worldwide [1–3]. For injection drug users (IDU), the annual rate of fatal overdose is estimated to between one and three per cent per year and is the primary contributor to mortality rates many times higher than in non-IDU populations [4– 7]. Thus, interventions to reduce mortality from overdose are central to efforts to reduce the harms of illicit drug use. In Vancouver, Canada, the number of fatal overdoses reached unprecedented levels at the end of the 1990s, especially in the Downtown Eastside (DTES) neighbourhood, the site of an open drug market and explosive outbreaks of HIV and hepatitis (HCV) [8]. In response, North America’s first medically supervised safer injecting facility (SIF), named Insite, opened in the DTES in March, 2003. The pilot facility has been the subject of a comprehensive evaluation [9,10]. Among its findings are a significant increase in uptake to drug and alcohol treatment [11]; a decrease in local measures of drug-related disorder, including public injecting [12]; and a reduction in the prevalence of risk factors for HIV infection, such as syringe sharing [13]. In addition to these public health objectives, the facility aims to reduce the risk of death for clients by providing prompt and appropriate medical attention in the event of an on-site overdose [9]. We have previously reported that the annual incidence of non- fatal overdose in a representative sample of SIF users was approximately 20 per 1,000 person years [14]; and that while on-site non-fatal overdoses were common during the first PLoS ONE | www.plosone.org 1 October 2008 | Volume 3 | Issue 10 | e3351