title: Mortality among patients with cleared hepatitis C virus infection compared to the general population: a Danish nationwide cohort study.
abstract: BACKGROUND
  The increased mortality in HCV-infected individuals partly stems from viral damage to the liver and partly from risk-taking behaviours. We examined mortality in patients who cleared their HCV-infection, comparing it to that of the general population. We also addressed the question whether prognosis differed according to age, substance abuse (alcohol abuse and injection drug use) and comorbidity.
  
  
  RESULTS
  Patients with cleared HCV-infection were categorized into one of 8 groups according to age (20-39 years or 40-69 years) and patient characteristics (no substance abuse/no comorbidity; substance abuse/no comorbidity; no substance abuse/comorbidity; and substance abuse/comorbidity). For each patient, 4 age- and gender-matched individuals without substance abuse or comorbidity were selected from the general population, comprising a total of 8 comparison cohorts. We analyzed 10-year survival and used stratified Cox Regression analysis to compute mortality rate ratios (MRRs), comparing mortality between the 8 patient groups and the comparison cohorts, adjusting for personal income. Among patients without substance abuse or comorbidity, those aged 40-69 years had the same mortality as the comparison cohort (10-year survival: 95% (95% confidence interval [CI]: 93%-97%), MRR: 1.3 (95% CI: 0.8-2.3)), whereas those aged 20-39 years had higher mortality than the comparison cohort (10-year survival: 93% versus 99%, MRR: 5.7 (95% CI: 2.3-14.0). For both age categories, substance abuse and comorbidity decreased survival and increased MRRs. Patients aged 40-69 years with substance abuse and comorbidity suffered from substantial mortality (MRR: 12.5 (95% CI: 5.1-30.6)).
  
  
  CONCLUSIONS
  Mortality in patients aged 40-69 years with cleared HCV-infection is comparable to individuals without HCV, provided they have no substance abuse or comorbidity. Any substance abuse and/or comorbidity not captured in the registries used for our study could explain the increased mortality in patients aged 20-39 years without documented substance abuse or comorbidity.
authors.affiliation: Department of Infectious Diseases, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark. omland@dadlnet.dk
authors.forename: Lars Haukali
authors.initials: LH
authors.lastname: Omland
authors.forename: Peer Brehm
authors.initials: PB
authors.lastname: Christensen
authors.forename: Henrik
authors.initials: H
authors.lastname: Krarup
authors.forename: Peter
authors.initials: P
authors.lastname: Jepsen
authors.forename: Nina
authors.initials: N
authors.lastname: Weis
authors.forename: Henrik Toft
authors.initials: HT
authors.lastname: Sørensen
authors.forename: Niels
authors.initials: N
authors.lastname: Obel
mesh_terms: D000328:Adult; D000437:Alcoholism / Q000401:mortality; D002423:Cause of Death; D015331:Cohort Studies; D015897:Comorbidity; D003718:Denmark / Q000453:epidemiology; D005260:Female; D016174:Hepacivirus / Q000502:physiology*; D006526:Hepatitis C / Q000401:mortality* / Q000821:virology*; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015819:Substance Abuse, Intravenous / Q000401:mortality