title: Prescription opioid injection and risk of hepatitis C in relation to traditional drugs of misuse in a prospective cohort of street youth.
abstract: OBJECTIVE
  Despite dramatic increases in the misuse of prescription opioids, the extent to which their intravenous injection places drug users at risk of acquiring hepatitis C virus (HCV) remains unclear. We sought to compare risk of HCV acquisition from injection of prescription opioids to that from other street drugs among high-risk street youth.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  Vancouver, British Columbia, Canada from September 2005 to November 2011.
  
  
  METHODS
  The At-Risk Youth Study (ARYS) is a prospective cohort of drug-using adolescents and young adults aged 14-26 years. Participants were recruited through street-based outreach and snowball sampling.
  
  
  METHODS
  HCV antibody seroconversion, measured every 6 months during follow-up. Risk for seroconversion from injection of prescription opioids was compared with injection of other street drugs of misuse, including heroin, cocaine or crystal methamphetamine, using Cox proportional hazards regression controlling for age, gender and syringe sharing.
  
  
  RESULTS
  Baseline HCV seropositivity was 10.6%. Among 512 HCV-seronegative youth contributing 860.2 person-years of follow-up, 56 (10.9%) seroconverted, resulting in an incidence density of 6.5/100 person-years. In bivariate analyses, prescription opioid injection (HR=3.48; 95% CI 1.57 to 7.70) predicted HCV seroconversion. However, in multivariate modelling, only injection of heroin (adjusted HR=4.56; 95% CI 2.39 to 8.70), cocaine (adjusted HR=1.88; 95% CI 1.00 to 3.54) and crystal methamphetamine (adjusted HR=2.91; 95% CI 1.57 to 5.38) remained independently associated with HCV seroconversion, whereas injection of prescription opioids did not (adjusted HR=0.94; 95% CI 0.40 to 2.21).
  
  
  CONCLUSIONS
  Although misuse of prescription opioids is on the rise, traditional street drugs still posed the greatest threat of HCV transmission in this setting. Nonetheless, the high prevalence and incidence of HCV among Canadian street youth underscore the need for evidence-based drug prevention, treatment and harm reduction interventions targeting this vulnerable population.
authors: Division of Adolescent & Young Adult Medicine, Department of Medicine, Boston Children's Hospital, Boston, Massachusetts, USA Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, USA.
authors: Scott E
authors: http://orcid.org/0000-0003-3189-6199
authors: SE
authors: Hadland
authors: British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, British Columbia, Canada School of Population and Public Health, University of British Columbia, Vancouver, British Columbia, Canada.
authors: Kora
authors: K
authors: DeBeck
authors: British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, British Columbia, Canada Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.
authors: Thomas
authors: T
authors: Kerr
authors: British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, British Columbia, Canada University of Saskatchewan, School of Public Health, Saskatoon, Saskatchewan, Canada.
authors: Cindy
authors: C
authors: Feng
authors: British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, British Columbia, Canada Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.
authors: Julio S
authors: JS
authors: Montaner
authors: British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, British Columbia, Canada Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.
authors: Evan
authors: E
authors: Wood
mesh_terms: D000293:Adolescent; D000328:Adult; D000701:Analgesics, Opioid / Q000008:administration & dosage*; D002170:Canada; D015331:Cohort Studies; D005260:Female; D006526:Hepatitis C / Q000453:epidemiology* / Q000209:etiology; D018453:Homeless Youth; D006801:Humans; D013287:Illicit Drugs; D008297:Male; D055553:Prescription Drugs / Q000008:administration & dosage*; D011446:Prospective Studies; D012306:Risk; D015819:Substance Abuse, Intravenous / Q000150:complications / Q000453:epidemiology*; D055815:Young Adult
chemical_list: D000701:Analgesics, Opioid; D013287:Illicit Drugs; D055553:Prescription Drugs
keywords: INFECTIOUS DISEASES