title: [Risk factors for hepatitis C among injecting drug users in Oslo].
abstract: BACKGROUND
  Hepatitis C virus (HCV) infection is common among injecting drug users. The aims of this study were to assess the prevalence of risk behaviour and its association with HCV infection.
  
  
  METHODS
  All users of the needle exchange program in Oslo, within a given time period, were eligible for inclusion in this cross-sectional study; 327 chose to participate. The users were asked about type of drug use and risk behaviour for HCV exposure in a structured interview. Sera were drawn and tested for anti HCV (EIA-3) and HCV RNA (in- house PCR).
  
  
  RESULTS
  The prevalence of HCV RNA was 51 % and 81 % had anti-HCV. A multivariate analysis revealed positive associations between anti-HCV positive status and age < 20 years at first injection, > 5 years of drug use, age > 34 years, sharing of syringes, injecting drug use while imprisoned, back-loading and use of heroin. One in five users with anti-HCV reported to never have shared syringes. However, sharing of drug paraphernalia other than needles was not associated with anti-HCV. Sharing of needles the last four weeks before the interview was more common among those living with a partner than those who lived alone.
  
  
  CONCLUSIONS
  Most injecting drug users in Oslo have been exposed to HCV (anti HCV+) and half of them have developed chronic infection (HCV RNA+). HCV was associated with back-loading and sharing of syringes - especially during incarceration. Sharing of injection paraphernalia was not associated with being anti HCV positive.
authors.affiliation: odalgard@medisin.uio.no Medisinsk avdeling Rikshospitalet 0027 Oslo.
authors.forename: Olav
authors.initials: O
authors.lastname: Dalgard
authors.forename: Atle
authors.initials: A
authors.lastname: Egeland
authors.forename: Randi
authors.initials: R
authors.lastname: Ervik
authors.forename: Kostas
authors.initials: K
authors.lastname: Vilimas
authors.forename: Kjell
authors.initials: K
authors.lastname: Skaug
authors.forename: Tore W
authors.initials: TW
authors.lastname: Steen
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D006526:Hepatitis C / Q000209:etiology / Q000635:transmission*; D019698:Hepatitis C, Chronic / Q000209:etiology / Q000635:transmission; D006801:Humans; D008297:Male; D016485:Needle Sharing / Q000009:adverse effects / Q000523:psychology; D018671:Needle-Exchange Programs; D009664:Norway; D012307:Risk Factors; D012309:Risk-Taking; D015819:Substance Abuse, Intravenous / Q000821:virology*; D011795:Surveys and Questionnaires