Jeanette M Bowles1, Sonia Jain2, Xiaoying Sun2, Steffanie A Strathdee3, Kora DeBeck4, M-J Milloy5, Zachary Bouck6, Dan Werb7. 1. Centre on Drug Policy Evaluation, Unity Health Toronto, 209 Victoria St, Toronto, ON M5B 1T8, Canada. 2. Biostatistics Research Center, Department of Family Medicine and Public Health, University of California San Diego, 9500 Gilman Dr, La Jolla, CA 92093, USA. 3. Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, 9500 Gilman Dr, La Jolla, CA 92093, United States. 4. British Columbia Centre on Substance Use, 1045 Howe St Suite 400, Vancouver, BC V6Z 2A9, Canada; School of Public Policy, Simon Fraser University, 8888 University Dr, Burnaby, BC V5A 1S6, Canada. 5. British Columbia Centre on Substance Use, 1045 Howe St Suite 400, Vancouver, BC V6Z 2A9, Canada; Department of Medicine, University of British Columbia, 317 - 2194 Health Sciences Mall, Vancouver, BC V6T 1Z3, Canada. 6. Centre on Drug Policy Evaluation, Unity Health Toronto, 209 Victoria St, Toronto, ON M5B 1T8, Canada; Epidemiology Division, Dalla Lana School of Public Health, University of Toronto, 155 College St Room 500, Toronto, ON M5T 3M7, Canada. 7. Centre on Drug Policy Evaluation, Unity Health Toronto, 209 Victoria St, Toronto, ON M5B 1T8, Canada; Biostatistics Research Center, Department of Family Medicine and Public Health, University of California San Diego, 9500 Gilman Dr, La Jolla, CA 92093, USA; Institute of Health Policy, Management and Evaluation, University of Toronto, 155 College St Room 425, Toronto, ON M5T 3M6, Canada. Electronic address: dwerb@health.ucsd.edu.
Abstract
BACKGROUND: Individuals who initiate injection drug use often receive assistance from an injection-knowledgeable peer. Persons who assist peers in injection initiation events often inject frequently, which heightens overdose risk. As such, overdose and injection initiation events may be correlated. To explore a potential relationship, we assessed temporal associations between experiencing a non-fatal overdose and assisting others in initiating injection drug use among persons who inject drugs in two North American cities - Vancouver, Canada and Tijuana, Mexico. METHODS: From 2014 to 2018, this retrospective cohort study included people who inject drugs from Vancouver (n=1332) and Tijuana (n=666) who completed a baseline and six-month follow-up interview. Within each site, we assessed bidirectional temporal associations using two separate multivariable logistic regression models: for model 1, recent provision of injection initiation assistance (at six months) was the outcome and recent overdose (at baseline) was the exposure; for model 2, recent overdose (at six months) was the outcome and recent provision of injection initiation assistance (at baseline) was the exposure. Both models adjusted for potential confounders. RESULTS: Vancouver-based participants reporting overdose at baseline had 163% greater odds of reporting provision of injection initiation assistance at follow-up (adjusted Odds Ratio [aOR] 2.63; 95% Confidence Interval [CI] 1.41-4.90); while participants reporting provision of injection initiation assistance at baseline had 89% greater odds of reporting a non-fatal overdose at follow-up (aOR 1.89; 95% CI 1.00-3.57). Among Tijuana-based participants, we did not observe a statistically significant association in either direction. CONCLUSION: Findings in Vancouver suggest that injection initiation assistance and overdose are bidirectionally-associated phenomena. The present findings highlight the need for interventions that ensure that persons who provide injection initiation assistance are given overdose prevention support, both for themselves and for those they assist to initiate injection drug use. While our Tijuana-based results did not suggest a bidirectional relationship, preventative approaches should nonetheless be undertaken.
BACKGROUND: Individuals who initiate injection drug use often receive assistance from an injection-knowledgeable peer. Persons who assist peers in injection initiation events often inject frequently, which heightens overdose risk. As such, overdose and injection initiation events may be correlated. To explore a potential relationship, we assessed temporal associations between experiencing a non-fatal overdose and assisting others in initiating injection drug use among persons who inject drugs in two North American cities - Vancouver, Canada and Tijuana, Mexico. METHODS: From 2014 to 2018, this retrospective cohort study included people who inject drugs from Vancouver (n=1332) and Tijuana (n=666) who completed a baseline and six-month follow-up interview. Within each site, we assessed bidirectional temporal associations using two separate multivariable logistic regression models: for model 1, recent provision of injection initiation assistance (at six months) was the outcome and recent overdose (at baseline) was the exposure; for model 2, recent overdose (at six months) was the outcome and recent provision of injection initiation assistance (at baseline) was the exposure. Both models adjusted for potential confounders. RESULTS: Vancouver-based participants reporting overdose at baseline had 163% greater odds of reporting provision of injection initiation assistance at follow-up (adjusted Odds Ratio [aOR] 2.63; 95% Confidence Interval [CI] 1.41-4.90); while participants reporting provision of injection initiation assistance at baseline had 89% greater odds of reporting a non-fatal overdose at follow-up (aOR 1.89; 95% CI 1.00-3.57). Among Tijuana-based participants, we did not observe a statistically significant association in either direction. CONCLUSION: Findings in Vancouver suggest that injection initiation assistance and overdose are bidirectionally-associated phenomena. The present findings highlight the need for interventions that ensure that persons who provide injection initiation assistance are given overdose prevention support, both for themselves and for those they assist to initiate injection drug use. While our Tijuana-based results did not suggest a bidirectional relationship, preventative approaches should nonetheless be undertaken.
Authors: Carl A Latkin; Rachel E Gicquelais; Catie Clyde; Lauren Dayton; Melissa Davey-Rothwell; Danielle German; Seun Falade-Nwulia; Haneefa Saleem; Michael Fingerhood; Karin Tobin Journal: Int J Drug Policy Date: 2019-04-23
Authors: Gillian Kolla; Carol Strike; Élise Roy; Jason Altenberg; Raffi Balian; Rey Silver; Neil Hunt Journal: Subst Use Misuse Date: 2015-11-23 Impact factor: 2.164
Authors: Peter J Davidson; Rachel L McLean; Alex H Kral; Alice A Gleghorn; Brian R Edlin; Andrew R Moss Journal: J Urban Health Date: 2003-06 Impact factor: 3.671