FACTORS ASSOCIATED WITH RIBAVIRIN-INDUCED ANEMIA
Frank K Friedenberg, Satya P Gollamudi, Alan W Chang, Manjushree Guatam, Joan K Schmutz, Kevin S Skole, Rebecca M Thomas, and Martin Black

BACKGROUND: During treatment of hepatitis C, ribavirin-induced anemia (RIA) requires reduction of the ribavirin dose or initiation of erythropoietin in up to 20% of patients. RIA usually occurs in the first 8 weeks of treatment, and a decrease >3 g/dL or a nadir <10 g/dL is considered significant.

OBJECTIVE: To prospectively examine factors associated with RIA in a population of patients with hepatitis C.

METHODS: Consecutive patients with hepatitis C (hepatitis B virus and HIV negative) underwent treatment with pegylated interferon and weight-based ribavirin. Prospectively gathered data included demographics, alcohol consumption, and hepatitis C virus risk factors. Patients underwent laboratory studies at baseline and at intervals of 4–8 weeks after starting treatment.

RESULTS: One hundred eight patients were enrolled. Of these, 30 (27.8%) experienced a >3 g/dL fall in hemoglobin levels in the first 8 weeks; in 10 (33%) patients, the change occurred by week 4. The initial hemoglobin level was higher in those with a decrease compared with those without a fall (15.3 vs 14.1 g/dL; p < 0.001). In addition, for patients with a decrease, the iron saturation was higher (44.6% vs 30.1%; p = 0.002). Finally, those with fibrosis stage 6/6 (cirrhosis) had a greater percent fall in hemoglobin (27.0% vs 14.0%; p = 0.009) than those with less severe fibrosis. By logistic regression analysis, only iron saturation was associated with RIA (p = 0.002).

CONCLUSIONS: In our patients, initial hemoglobin, serum iron, and fibrosis were associated with a potentially clinically important decrease in hemoglobin. In approximately one-third of the population, RIA occurred in the first 4 weeks of treatment. No patient had a severe complication.

J Pharm Technol 2005;21:207-12.