title: Anemia associated with antiviral therapy in chronic hepatitis C: incidence, risk factors, and impact on treatment response.
abstract: BACKGROUND
  One major side effect of combination antiviral therapy is the development of anemia, which is more severe among the Asian population. We conducted this large-scaled study to explore the incidence, risk factors, and impact on treatment response of anemia in chronic hepatitis C patients receiving combination antiviral therapy.
  
  
  METHODS
  Four hundred and sixty-six chronic hepatitis C patients were treated with interferon-alpha-2b (IFN-alpha-2b) three or five million units thrice weekly, or pegylated-IFN-alpha-2b 1-1.5 microg/kg weekly plus ribavirin (1000-1200 mg/day) for 24 weeks. Severe anemia was defined as hemoglobin concentration <10 g/dl.
  
  
  RESULTS
  The mean decrease of hemoglobin was 3.9+/-1.3 g/dl. Thirty-nine percent of patients had developed severe anemia during therapy. Stepwise logistic regression analysis revealed that old age (> or =50 years) (odds ratio [OR]=1.935, P=0.001) and baseline hemoglobin level (> or =14 g/dl) (OR=2.975, P<0.001) were significantly correlated with maximal decreases in hemoglobin. Using Cox's regression analysis, pretreatment platelet counts (<150 000/mm(3)) (OR=1.821, P<0.001), old age (> or =50 years) (OR=1.789, P=0.001), female gender (OR=1.739, P<0.001), and low body weight (<65 kg) (OR=1.493, P=0.027) were independent factors contributing to severe anemia. There was a significant linear correlation between the sustained virological response (SVR) rate and the time of severe anemia during therapy (r=0.774, P=0.003), especially among genotype 1 patients (r=0.960, P<0.001).
  
  
  CONCLUSIONS
  Careful monitoring of hemoglobin level is necessary in patients who are old, female and have low body weight and platelet counts. Development of severe anemia was significantly correlated with the SVR.
authors.affiliation: Division of Hepatogastroenterology, Department of Internal Medicine, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Chang Gung University College of Medicine, Kaohsiung, Taiwan.
authors.forename: Chao-Hung
authors.initials: CH
authors.lastname: Hung
authors.forename: Chuan-Mo
authors.initials: CM
authors.lastname: Lee
authors.forename: Sheng-Nan
authors.initials: SN
authors.lastname: Lu
authors.forename: Jing-Houng
authors.initials: JH
authors.lastname: Wang
authors.forename: Chien-Hung
authors.initials: CH
authors.lastname: Chen
authors.forename: Tsung-Hui
authors.initials: TH
authors.lastname: Hu
authors.forename: Kwong-Ming
authors.initials: KM
authors.lastname: Kee
authors.forename: Kuo-Chin
authors.initials: KC
authors.lastname: Chang
authors.forename: Po-Lin
authors.initials: PL
authors.lastname: Tseng
authors.forename: Yi-Hao
authors.initials: YH
authors.lastname: Yen
authors.forename: Chi-Sin
authors.initials: CS
authors.lastname: Changchien
mesh_terms: D000367:Age Factors; D000740:Anemia / Q000097:blood / Q000139:chemically induced* / Q000453:epidemiology; D000998:Antiviral Agents / Q000009:adverse effects* / Q000627:therapeutic use; D001835:Body Weight; D004359:Drug Therapy, Combination; D005260:Female; D006454:Hemoglobins / Q000378:metabolism; D019698:Hepatitis C, Chronic / Q000188:drug therapy*; D006801:Humans; D015994:Incidence; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D010976:Platelet Count; D011092:Polyethylene Glycols; D016016:Proportional Hazards Models; D011994:Recombinant Proteins; D012254:Ribavirin / Q000009:adverse effects; D012307:Risk Factors; D012720:Severity of Illness Index; D012737:Sex Factors; D016896:Treatment Outcome
chemical_list: D000998:Antiviral Agents; D006454:Hemoglobins; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D011994:Recombinant Proteins; D011092:Polyethylene Glycols; D012254:Ribavirin; C417083:peginterferon alfa-2b