title: Pretreatment prediction of anemia progression by pegylated interferon alpha-2b plus ribavirin combination therapy in chronic hepatitis C infection: decision-tree analysis.
abstract: BACKGROUND
  This study aimed to develop a model to predict the development of severe anemia during pegylated interferon alpha-2b plus ribavirin combination therapy.
  
  
  METHODS
  Data were collected from 1081 genotype 1b chronic hepatitis C patients who were treated at 6 hospitals in Japan. These patients were randomly assigned to a model-building group (n = 691) or an internal validation group (n = 390). Factors predictive of severe anemia (hemoglobin, Hb < 8.5 g/dl) were explored using data-mining analysis.
  
  
  RESULTS
  Hb values at baseline, creatinine clearance (Ccr), and an Hb concentration decline by 2 g/dl at week 2 were used to build a decision-tree model, in which the patients were divided into 5 subgroups based on variable rates of severe anemia ranging from 0.4 to 11.8%. The reproducibility of the model was confirmed by the internal validation group (r² = 0.96). The probability of severe anemia was high in patients whose Hb value was <14 g/dl before treatment (6.5%), especially (a) in those whose Ccr was <80 ml/min (11.8%) and (b) those whose Ccr was ≥ 80 ml/min but whose Hb concentration decline at week 2 was ≥ 2 g/dl (11.5%). The probability of severe anemia was low in the other patients (0.4-2.5%).
  
  
  CONCLUSIONS
  The decision-tree model that included Hb values at baseline, Ccr, and an Hb concentration decline by 2 g/dl at week 2 was useful for predicting the probability of severe anemia, and has the potential to support clinical decisions regarding early dose reduction of ribavirin.
authors.affiliation: Department of Gastroenterology and Hepatology, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Hiramatsu
authors.forename: Masayuki
authors.initials: M
authors.lastname: Kurosaki
authors.forename: Naoya
authors.initials: N
authors.lastname: Sakamoto
authors.forename: Manabu
authors.initials: M
authors.lastname: Iwasaki
authors.forename: Minoru
authors.initials: M
authors.lastname: Sakamoto
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Fuminaka
authors.initials: F
authors.lastname: Sugauchi
authors.forename: Akihiro
authors.initials: A
authors.lastname: Tamori
authors.forename: Sei
authors.initials: S
authors.lastname: Kakinnuma
authors.forename: Kentaro
authors.initials: K
authors.lastname: Matsuura
authors.forename: Namiki
authors.initials: N
authors.lastname: Izumi
mesh_terms: D000328:Adult; D000368:Aged; D000743:Anemia, Hemolytic / Q000139:chemically induced*; D000998:Antiviral Agents / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D015331:Cohort Studies; D003663:Decision Trees; D018450:Disease Progression; D004305:Dose-Response Relationship, Drug; D004359:Drug Therapy, Combination; D005260:Female; D005838:Genotype; D016174:Hepacivirus / Q000235:genetics; D019698:Hepatitis C, Chronic / Q000188:drug therapy / Q000821:virology; D006801:Humans; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000008:administration & dosage / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D011092:Polyethylene Glycols / Q000008:administration & dosage / Q000627:therapeutic use; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000627:therapeutic use; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012254:Ribavirin / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D012720:Severity of Illness Index
chemical_list: D000998:Antiviral Agents; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D011994:Recombinant Proteins; D011092:Polyethylene Glycols; D012254:Ribavirin; C417083:peginterferon alfa-2b