title: Association between neighbourhood socioeconomic characteristics and high-risk injection behaviour amongst injection drug users living in inner and other city areas in Montréal, Canada.
abstract: BACKGROUND
  Area-level socioeconomic conditions are associated with epidemic rates of viral hepatitis and HIV amongst urban injection drug users (IDUs), but whether specific socioeconomic markers are uniformly related to IDU outcomes across different urban environments is unclear. We evaluated whether injection behaviour is differentially related to neighbourhood socioeconomic characteristics for IDUs in inner city vs. surrounding urban areas.
  
  
  METHODS
  The study population was 468 active IDUs on the Island of Montréal. Neighbourhoods were represented as 500m radius buffers around individual IDU dwelling places. High-risk injection behaviour (HRIB) was defined dichotomously. Relations between neighbourhood socioeconomic disadvantage (percentage households below low-income cutoff), neighbourhood educational attainment (percentage adults with university degree), and HRIB were assessed using multivariate logistic regression. Stratified analyses were conducted for inner city IDUs (n=219), and those in surrounding areas (n=249).
  
  
  RESULTS
  Similar proportions of IDUs in inner city and surrounding areas reported HRIB. Neighbourhood socioeconomic characteristics were not associated with HRIB for IDUs in surrounding areas. For inner city IDUs, those in socioeconomically disadvantaged neighbourhoods were more likely to practice HRIB (OR 4.34; 95% CI 1.15-16.35). Conversely, inner city IDUs residing in lower educational attainment neighbourhoods had a lower odds of HRIB (OR 0.41; 95% CI 0.21-0.80).
  
  
  CONCLUSIONS
  HRIB did not vary according to urban environment but for inner-city IDUs was differentially related to socioeconomic markers. Associations between HRIB and neighbourhood socioeconomic disadvantage and lower educational attainment, positive and negative, respectively, indicate that adverse socioeconomic circumstances are not related to a uniformly greater likelihood of HRIB.
authors.affiliation: Community Medicine Residency Program, Université de Montréal, Québec, Canada.
authors.forename: Mélissa
authors.initials: M
authors.lastname: Généreux
authors.forename: Julie
authors.initials: J
authors.lastname: Bruneau
authors.forename: Mark
authors.initials: M
authors.lastname: Daniel
mesh_terms: D000328:Adult; D003617:Dangerous Behavior; D004522:Educational Status; D005260:Female; D006801:Humans; D007182:Income; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D016485:Needle Sharing / Q000706:statistics & numerical data; D011792:Quebec; D012111:Residence Characteristics / Q000706:statistics & numerical data*; D012959:Socioeconomic Factors; D015819:Substance Abuse, Intravenous / Q000097:blood / Q000523:psychology*; D011795:Surveys and Questionnaires; D014505:Urban Population / Q000706:statistics & numerical data*; D055815:Young Adult