title: Risk factors for hepatitis C virus infection among injecting drug users in Sydney.
abstract: OBJECTIVE
  To study risk factors for hepatitis C virus (HCV) infection in injecting drug users (IDUs) from central Sydney.
  
  
  METHODS
  All IDUs attending a primary health care facility in central Sydney between December 1991 and November 1992 who underwent HCV antibody testing.
  
  
  METHODS
  Information was obtained retrospectively from client forms routinely completed at the time of medical consultation. Additional information on injecting history and practice was obtained from the registration forms of subjects who also attended the needle syringe exchange programme at the same health care facility.
  
  
  RESULTS
  Of the 201 IDUs tested, 118 (59%) had HCV antibodies, which did not differ significantly between males and females. HCV prevalence increased significantly with age, being highest in IDUs who were aged 35 years or more (93%) and lowest in IDUs aged under 20 years (17%). HCV prevalence increased significantly with time since first injecting, from 26% for IDUs who had injected for less than 3 years to 94% for those who had injected for more than 10 years. HCV prevalence was also significantly higher in heterosexual IDUs as compared with homosexual male IDUs, and in opiate users as compared with stimulant users, even after adjustment for age and duration of injecting. HCV prevalence was strongly associated with exposure to hepatitis B virus, but was not associated with exposure to HIV.
  
  
  CONCLUSIONS
  Recent HCV transmission indicates ongoing injecting risk behaviour despite HIV prevention efforts, and underlies the potential for increased transmission of HIV through the sharing of injecting equipment. Within the population of IDUs, those who are heterosexual or inject heroin appear to be at increased risk of HCV infection.
authors.affiliation: Kirketon Road Centre, Sydney, New South Wales, Australia.
authors.forename: I
authors.initials: I
authors.lastname: van Beek
authors.forename: R
authors.initials: R
authors.lastname: Buckley
authors.forename: M
authors.initials: M
authors.lastname: Stewart
authors.forename: M
authors.initials: M
authors.lastname: MacDonald
authors.forename: J
authors.initials: J
authors.lastname: Kaldor
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000697:Central Nervous System Stimulants; D015331:Cohort Studies; D005260:Female; D006526:Hepatitis C / Q000453:epidemiology*; D006716:Homosexuality; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009294:Narcotics; D009517:New South Wales / Q000453:epidemiology; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D011477:Sex Work; D015819:Substance Abuse, Intravenous / Q000453:epidemiology*; D013997:Time Factors
chemical_list: D000697:Central Nervous System Stimulants; D009294:Narcotics