title: Associations between childhood trauma and non-fatal overdose among people who inject drugs.
abstract: BACKGROUND
  Although people who inject drugs (IDU) remain at a high risk of accidental overdose, interventions that address overdose remain limited. Accordingly there is a continuing need to identify psychological and social factors that shape overdose risk. Despite being reported frequently among IDU, childhood trauma has received little attention as a potential risk factor for overdose. This study aims to evaluate relationships between non-fatal overdose and five forms of childhood maltreatment among a cohort of IDU in Vancouver, Canada.
  
  
  METHODS
  Data was obtained from two prospective cohorts of IDU between December 2005 and May 2013. Multivariate generalized estimating equations (GEEs) were used to explore relationships between five forms of childhood trauma and non-fatal overdose, adjusting for potential confounders.
  
  
  RESULTS
  During the study period, 1697 IDU, including 552 (32.5%) women, were followed up. At baseline, 1136 (67.0%) participants reported at least one form of childhood trauma, while 4-9% reported a non-fatal overdose at each semi-annual follow-up. In multivariate analyses, physical [adjusted odds ratio (AOR): 1.36, 95% confidence interval (CI): 1.08-1.71], sexual (AOR: 1.48, CI: 1.17-1.87), and emotional abuse (AOR: 1.54, CI: 1.22-1.93) and physical neglect (AOR: 1.28, CI: 1.01-1.62) were independently associated with non-fatal overdose (all p<0.05).
  
  
  CONCLUSIONS
  Childhood trauma was common among participants, and reporting an experience of trauma was positively associated with non-fatal overdose. These findings highlight the need to provide intensive overdose prevention to trauma survivors and to incorporate screening for childhood trauma into health and social programs tailored to IDU.
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, 608-1081 Burrard Street, Vancouver, BC V6Z 1Y6, Canada; School of Population and Public Health, University of British Columbia, 2206 East Mall, Vancouver, BC V6T 1Z9, Canada.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Lake
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, 608-1081 Burrard Street, Vancouver, BC V6Z 1Y6, Canada.
authors.forename: Kanna
authors.initials: K
authors.lastname: Hayashi
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, 608-1081 Burrard Street, Vancouver, BC V6Z 1Y6, Canada; Department of Medicine, University of British Columbia, St. Paul's Hospital, 608-1081 Burrard Street, Vancouver, BC V6Z 1Y6, Canada.
authors.forename: M-J
authors.initials: MJ
authors.lastname: Milloy
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, 608-1081 Burrard Street, Vancouver, BC V6Z 1Y6, Canada; Department of Medicine, University of British Columbia, St. Paul's Hospital, 608-1081 Burrard Street, Vancouver, BC V6Z 1Y6, Canada.
authors.forename: Evan
authors.initials: E
authors.lastname: Wood
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, 608-1081 Burrard Street, Vancouver, BC V6Z 1Y6, Canada.
authors.forename: Huiru
authors.initials: H
authors.lastname: Dong
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, 608-1081 Burrard Street, Vancouver, BC V6Z 1Y6, Canada; Department of Medicine, University of British Columbia, St. Paul's Hospital, 608-1081 Burrard Street, Vancouver, BC V6Z 1Y6, Canada.
authors.forename: Julio
authors.initials: J
authors.lastname: Montaner
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, 608-1081 Burrard Street, Vancouver, BC V6Z 1Y6, Canada; Department of Medicine, University of British Columbia, St. Paul's Hospital, 608-1081 Burrard Street, Vancouver, BC V6Z 1Y6, Canada. Electronic address: uhri-tk@cfenet.ubc.ca.
authors.forename: Thomas
authors.initials: T
authors.lastname: Kerr
mesh_terms: D000328:Adult; D001955:British Columbia / Q000453:epidemiology; D002648:Child; D002649:Child Abuse / Q000523:psychology*; D019970:Cocaine-Related Disorders / Q000453:epidemiology / Q000523:psychology; D062787:Drug Overdose / Q000523:psychology; D005260:Female; D006556:Heroin Dependence / Q000453:epidemiology / Q000523:psychology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015819:Substance Abuse, Intravenous / Q000453:epidemiology / Q000523:psychology*
keywords: Childhood abuse; Childhood maltreatment; Childhood neglect; Injection drug use; Non-fatal overdose