title: Needle exchange and sexual risk behaviors among a cohort of injection drug users in Chicago, Illinois.
abstract: OBJECTIVE
  To examine the impact of a needle exchange program (NEP) on sexual risk behaviors of injecting drug users (IDUs).
  
  
  METHODS
  : Between 1997 and 2000, 889 IDUs in Chicago were recruited from NEPs and an area with no NEP into a cohort study. They were interviewed and tested for HIV at baseline and 3 annual follow-up visits. Random-effect logistic models were used to compare NEP users and nonusers regarding the number of sex partners, number of unprotected sex acts, and frequency of condom use.
  
  
  RESULTS
  Compared to NEP nonusers, NEP users had a similar number of sex partners over time, but had 49% higher odds of using condoms with their main partners (P = 0.047). At baseline, there was no difference between NEP users and nonusers in episodes of vaginal intercourse, but over time the odds of having a higher number of unprotected instances of vaginal intercourse were reduced by 26% per year for NEP users but only 10% per year for nonusers (P = 0.02).
  
  
  CONCLUSIONS
  This study suggests that NEP participation may help reduce the absolute risk of HIV sexual transmission.
authors.affiliation: Department of Health Studies, University of Chicago, Chicago, Illinois 60637, USA. dhuo@health.bsd.uchicago.edu
authors.forename: Dezheng
authors.initials: D
authors.lastname: Huo
authors.forename: Lawrence J
authors.initials: LJ
authors.lastname: Ouellet
mesh_terms: D000328:Adult; D002641:Chicago / Q000453:epidemiology; D015331:Cohort Studies; D017280:Condoms / Q000706:statistics & numerical data; D005260:Female; D015658:HIV Infections / Q000453:epidemiology / Q000517:prevention & control* / Q000635:transmission; D006801:Humans; D008297:Male; D018671:Needle-Exchange Programs; D015397:Program Evaluation; D012309:Risk-Taking; D012725:Sexual Behavior / Q000706:statistics & numerical data*; D012747:Sexual Partners; D012749:Sexually Transmitted Diseases / Q000453:epidemiology / Q000517:prevention & control / Q000635:transmission; D015819:Substance Abuse, Intravenous / Q000150:complications / Q000453:epidemiology*; D047568:Unsafe Sex / Q000706:statistics & numerical data