title: Predictors of hepatitis B and C infection in injecting drug users both in and out of drug treatment.
abstract: OBJECTIVE
  To assess prevalence of, and behavioural risk factors for, hepatitis B and C in drug users both in and out of contact with drugs services.
  
  
  METHODS
  Cross-sectional survey of hepatitis B and C prevalence using blood samples and self-completed risk factor questionnaires.
  
  
  METHODS
  Three hundred and sixty injecting drug users (IDUs) in treatment for their drug use, attending syringe exchange schemes (SES), and not in contact with any services in Wirral and Manchester between 1997 and 1999, for whom test results were available for 334 (hepatitis B) and 341 (hepatitis C).
  
  
  RESULTS
  Hepatitis B prevalence differed between groups, from 19% of those not in contact to 41% of those presenting to request a test (p = 0.040). Prevalence of hepatitis C ranged from 48% (SES) to 62% among those presenting for a test (p = 0.233). After multivariate adjustment, hepatitis B was predicted by prison stays (p = 0.030) and injecting for longer (p = 0.003). For hepatitis C, length of injecting career (p = 0.036), having been to prison (p = 0.034), having injected more than one drug type (p < 0.001) and being female (p = 0.037) predicted infection. Overall, 38% had shared some form of injecting equipment in the previous 4 weeks. People recently starting injecting were more likely to share, and sharing was more likely to occur when injecting with only one other user rather than in larger groups. Those who had previously presented for a hepatitis C test, regardless of the result, were less likely to have recently shared injecting equipment.
  
  
  CONCLUSIONS
  Behaviours associated with transmission of hepatitis B and C are common among IDUs. In particular, sharing of injecting equipment was more likely in small groups and in those recently beginning injecting. More broadly, chaotic drug use and time in prison were also risk factors for hepatitis infections. When assessing prevalence of hepatitis B and C, our results suggest that figures cannot be extrapolated from those in service contact to those in the wider drug-using population.
authors.affiliation: Public Health Sector, School of Health and Human Sciences, Liverpool John Moores University, Liverpool, UK. p.a.cook@livjm.ac.uk
authors.forename: P A
authors.initials: PA
authors.lastname: Cook
authors.forename: J
authors.initials: J
authors.lastname: McVeigh
authors.forename: Q
authors.initials: Q
authors.lastname: Syed
authors.forename: K
authors.initials: K
authors.lastname: Mutton
authors.forename: M A
authors.initials: MA
authors.lastname: Bellis
mesh_terms: D000328:Adult; D017668:Age of Onset; D016001:Confidence Intervals; D003430:Cross-Sectional Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D019694:Hepatitis B, Chronic / Q000453:epidemiology / Q000209:etiology*; D019698:Hepatitis C, Chronic / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D016015:Logistic Models; D008297:Male; D016485:Needle Sharing; D016017:Odds Ratio; D010342:Patient Acceptance of Health Care; D016133:Polymerase Chain Reaction; D015995:Prevalence; D011329:Prisoners; D012307:Risk Factors; D012737:Sex Factors; D012725:Sexual Behavior; D015819:Substance Abuse, Intravenous / Q000150:complications* / Q000453:epidemiology / Q000628:therapy; D006113:United Kingdom / Q000453:epidemiology