title: Increases in the availability of prescribed opioids in a Canadian setting.
abstract: BACKGROUND
  The nonmedical use of prescribed opioids (POs) has increased across North America over the past decade. Our objective was to identify changes in the availability of POs and other illicit drugs among drug users in a Canadian setting.
  
  
  METHODS
  Information on the availability of illicit drugs was collected in standardized interviews from a large observational research program involving illicit drug users in Vancouver, British Columbia from 2006 to 2010. The primary outcome was the perceived availability of a set of six POs (aspirin/oxycodone, hydromorphone, oxycodone, morphine, acetaminophen/codeine and methadone) among individuals reporting ever using POs. Availability was measured in three levels: not available, delayed availability (available ≥10 min), and immediate availability (available <10 min). Multivariate ordinal logistic regression models were executed to estimate the trend in PO availability, controlling for individual characteristics hypothesized to influence availability.
  
  
  RESULTS
  1871 individuals were followed during the study period (2006-2010), including 583 (31.2%) women. The availability of POs increased over time, regardless of changes in the characteristics of cohort entrants. These increases were observed while the availability of traditional drugs of abuse (e.g., heroin and cocaine) remained constant. The adjusted odds of delayed availability vs. unavailability were between 34% (hydromorphone) and 71% (acetaminophen/codeine) greater in each calendar year.
  
  
  CONCLUSIONS
  The availability of POs among drug users in a Canadian setting increased markedly over a relatively short timeframe, despite persistent and high availability of heroin and cocaine. Further study is required to determine the context of use of POs, associated harms, as well as policy responses to increasing availability.
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, University of British Columbia, 608-1081 Burrard Street, Vancouver, BC, Canada V6Z 1Y6. bnosyk@cfenet.ubc.ca
authors.forename: B
authors.initials: B
authors.lastname: Nosyk
authors.forename: B D L
authors.initials: BD
authors.lastname: Marshall
authors.forename: B
authors.initials: B
authors.lastname: Fischer
authors.forename: J S G
authors.initials: JS
authors.lastname: Montaner
authors.forename: E
authors.initials: E
authors.lastname: Wood
authors.forename: T
authors.initials: T
authors.lastname: Kerr
mesh_terms: D000328:Adult; D000701:Analgesics, Opioid; D001955:British Columbia / Q000453:epidemiology; D002170:Canada / Q000453:epidemiology; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009293:Opioid-Related Disorders / Q000453:epidemiology*; D055553:Prescription Drugs; D011446:Prospective Studies; D055815:Young Adult
chemical_list: D000701:Analgesics, Opioid; D055553:Prescription Drugs