title: Receiver operating characteristics curve analysis of factors predictive of nonresponse to interferon therapy in patients with chronic hepatitis C.
abstract: OBJECTIVE
  1) to identify pretreatment variables predictive of nonresponse to interferon-alpha (IFN-alpha) in patients with chronic hepatitis C, and 2) to establish a prognostic index in these groups using receiver operating characteristics curve analysis.
  
  
  METHODS
  132 patients were treated with IFN-alpha at a dose of 3 megaunits three times a week for 3-12 months. The response was compared in patients with a complete response vs nonresponders, and patients with a sustained response vs nonresponders plus relapsers. Factors predictive of response were identified by analyzing clinical, biochemical, virological and histological variables.
  
  
  RESULTS
  The sustained response rate was 12.8% at 24 months of follow-up. The pretreatment characteristics with a predictive value (PV) according to area under the ROC curve and 95% confidence interval > 0.5 were age, known duration of infection, history of transfusion, GGT, serum ferritin levels, viral load, genotype, and grade and stage of the histological lesion. The positive PV (the probability of predicting absence of response when the variable is present) was notably greater than the negative PV (mean: 94.9% vs 24.8%, respectively). In addition, when 4 and 6 variables were present, the positive PV was 100% and sensitivity was 60.2% and 22.1%, respectively. The predictive variables independently associated with an absence of response were genotypes 1, 4 and 5, GGT > 24 IU/l and grade of the histological lesion > 6.
  
  
  CONCLUSIONS
  It was possible to predict the absence of both primary and posttreatment response with an acceptable degree of reliability.
authors.affiliation: Digestive Medicine Service, Hospital La Fe, Valencia.
authors.forename: V
authors.initials: V
authors.lastname: Olaso
authors.forename: J
authors.initials: J
authors.lastname: Córdoba
authors.forename: M S
authors.initials: MS
authors.lastname: Siles
authors.forename: J M
authors.initials: JM
authors.lastname: Molina
authors.forename: L
authors.initials: L
authors.lastname: Argüello
authors.forename: M V
authors.initials: MV
authors.lastname: Aguilera
authors.forename: G
authors.initials: G
authors.lastname: Bastida
authors.forename: B
authors.initials: B
authors.lastname: López Viedma
authors.forename: R
authors.initials: R
authors.lastname: Esteban
authors.forename: J
authors.initials: J
authors.lastname: Berenguer
authors.forename: M
authors.initials: M
authors.lastname: Segovia
mesh_terms: D000328:Adult; D000998:Antiviral Agents / Q000627:therapeutic use*; D005260:Female; D019698:Hepatitis C, Chronic / Q000188:drug therapy*; D006801:Humans; D007372:Interferons / Q000627:therapeutic use*; D008297:Male; D011237:Predictive Value of Tests; D011379:Prognosis; D012372:ROC Curve; D017211:Treatment Failure
chemical_list: D000998:Antiviral Agents; D007372:Interferons