title: Declining trends in the rates of assisted injecting: a prospective cohort study.
abstract: BACKGROUND
  Assisted injecting has been associated with increased risk of blood-borne infections, overdose, and other harms among people who inject drugs (PWID), particularly women. Given the changing availability of relevant harm reduction interventions in Vancouver, Canada, in recent years, we conducted a gender-based analysis to examine changes in rates and correlates of assisted injecting over time among active PWID.
  
  
  METHODS
  Using data from a prospective cohort of PWID in Vancouver, we employed gender-stratified multivariable generalized estimating equations to examine trends in assisted injecting and identify the correlates during two periods: June 2006-November 2009 and December 2009-May 2014.
  
  
  RESULTS
  Among 1119 participants, 376 (33.6 %) were females. Rates of assisted injecting declined between 2006 and 2014 among males (21.9 to 13.8%) and females (37.0 to 25.6%). In multivariable analyses, calendar year of interview also remained independently and negatively associated with assisted injecting among males (adjusted odds ratio [AOR] 0.95, 95% confidence interval [CI] 0.92-0.99) and females (AOR 0.93, 95% CI 0.89-0.97). Syringe borrowing remained independently associated with assisted injecting throughout the study period among females (AOR 1.53, 95% CI 1.10-2.11 during 2006-2009; AOR 2.15, 95% CI 1.24-3.74 during 2009-2014) and during 2009-2014 among males (AOR 1.88, 95% CI 1.02-3.48).
  
  
  CONCLUSIONS
  Our findings demonstrate assisted injecting has significantly decreased for both males and females over the past decade. Nevertheless, rates of assisted injecting remain high, especially among women, and are associated with high-risk behavior, indicating a need to provide safer assisted injecting services to these vulnerable sub-populations of PWID.
authors.affiliation: Cumming School of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, AB, T2N 4N1, Canada. jspeders@ucalgary.ca.
authors.forename: Jeanette Somlak
authors.initials: JS
authors.lastname: Pedersen
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, 608-1081 Burrard Street, Vancouver, BC, V6Z 1Y6, Canada. hdong@cfenet.ubc.ca.
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. wsmall@cfenet.ubc.ca.|Faculty of Health Sciences, Simon Fraser University, 8888 University Drive, Burnaby, BC, 15A 1S6, Canada. wsmall@cfenet.ubc.ca.
authors.forename: Will
authors.initials: W
authors.lastname: Small
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, 608-1081 Burrard Street, Vancouver, BC, V6Z 1Y6, Canada. uhri-ew@cfenet.ubc.ca.|Department of Medicine, University of British Columbia, St. Paul's Hospital, 608-1081 Burrard Street, Vancouver, BC, V6Z 1Y6, Canada. uhri-ew@cfenet.ubc.ca.
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. pnguyen@cfenet.ubc.ca.
authors.forename: Paul
authors.initials: P
authors.lastname: Nguyen
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, 608-1081 Burrard Street, Vancouver, BC, V6Z 1Y6, Canada. uhri-tk@cfenet.ubc.ca.|Department of Medicine, University of British Columbia, St. Paul's Hospital, 608-1081 Burrard Street, Vancouver, BC, V6Z 1Y6, Canada. uhri-tk@cfenet.ubc.ca.
authors.forename: Thomas
authors.initials: T
authors.lastname: Kerr
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, St. Paul's Hospital, 608-1081 Burrard Street, Vancouver, BC, V6Z 1Y6, Canada. khayashi@cfenet.ubc.ca.|Department of Medicine, University of British Columbia, St. Paul's Hospital, 608-1081 Burrard Street, Vancouver, BC, V6Z 1Y6, Canada. khayashi@cfenet.ubc.ca.|B.C. Centre for Excellence in HIV/AIDS, University of British Columbia, St. Paul's Hospital, 608-1081 Burrard Street, Vancouver, BC, V6Z 1Y6, Canada. khayashi@cfenet.ubc.ca.
authors.forename: Kanna
authors.initials: K
authors.lastname: Hayashi
mesh_terms: D000328:Adult; D001955:British Columbia / Q000453:epidemiology; D015331:Cohort Studies; D005260:Female; D040261:Harm Reduction; D006801:Humans; D008297:Male; D008875:Middle Aged; D016485:Needle Sharing / Q000706:statistics & numerical data; D011446:Prospective Studies; D012309:Risk-Taking; D012737:Sex Factors; D012959:Socioeconomic Factors; D015819:Substance Abuse, Intravenous / Q000453:epidemiology*
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