Accelerated decline of lung function in COPD patients with chronic hepatitis C virus infection: a preliminary study based on small numbers of patients.

STUDY OBJECTIVES It has been suggested that chronic viral infection may increase the risk for development of COPD. This prospective study was designed to determine that chronic hepatitis C virus (HCV) infection is associated with accelerated decline of lung function in patients with COPD, and that antiviral therapy against HCV is effective for such patients. DESIGN Prospective 5-year follow-up study. SETTING University hospital. PATIENTS Fifty-nine patients with COPD (group A, 15 HCV-negative ex-smokers; group B, 14 HCV-negative current smokers; group C, 14 HCV-positive ex-smokers; group D, 16 HCV-positive current smokers). INTERVENTIONS After a 5-year follow-up period, 21 HCV-positive patients received interferon (IFN)-alpha therapy. MEASUREMENTS AND RESULTS The rate of annual decline in FEV(1) and diffusing capacity of the lung for carbon monoxide (DLCO) during the 5-year follow-up period were significantly higher in group B (DeltaFEV(1), 59.7 mL/yr [SD, 17.5], p = 0.0008; DeltaDLCO, 3.50%/yr [SD, 0.44], p < 0.0001) and group C (DeltaFEV(1), 54.0 mL/yr [SD, 15.3], p = 0.0128; DeltaDLCO, 3.36%/yr [SD, 0.28], p < 0.0001) than in group A (DeltaFEV(1), 33.5 mL/yr [SD, 7.7]; DeltaDLCO, 2.66%/yr [SD, 0.34]). Moreover, these parameters in group D (DeltaFEV(1), 79.5 mL/yr [SD, 20.6]; DLCO, 4.5%/yr [SD, 0.40]) were also significantly higher than those in group B and group C. We evaluated the DeltaFEV(1) after IFN therapy during the 3-year follow-up period in the 8 IFN responders and 13 IFN nonresponders. DeltaFEV(1) in the IFN nonresponders did not significantly change during the 3-year follow-up period (before, 65.5 mL/yr [SD, 23.5]; after, 66.1 mL/yr [SD, 24.0]). However, DeltaFEV(1) in the IFN responders significantly decreased (before, 68.4 mL/yr [SD, 26.2]; after, 57.3 mL/yr [SD, 23.6], p = 0.0116). CONCLUSIONS Our findings suggest that chronic HCV infection might accelerate decline in lung function in patients who already have COPD.