Anemia associated with antiviral therapy in chronic hepatitis C: incidence, risk factors, and impact on treatment response.
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.
Hung
Chao-Hung
CH
Division of Hepatogastroenterology, Department of Internal Medicine, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Chang Gung University College of Medicine, Kaohsiung, Taiwan.
Lee
Chuan-Mo
CM
Lu
Sheng-Nan
SN
Wang
Jing-Houng
JH
Chen
Chien-Hung
CH
Hu
Tsung-Hui
TH
Kee
Kwong-Ming
KM
Chang
Kuo-Chin
KC
Tseng
Po-Lin
PL
Yen
Yi-Hao
YH
Changchien
Chi-Sin
CS
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
D000998:Antiviral Agents; D006454:Hemoglobins; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D011994:Recombinant Proteins; D011092:Polyethylene Glycols; D012254:Ribavirin; C417083:peginterferon alfa-2b