Abstract Background: Adverse events attributed to the treatment of chronic hepatitis C patients with pegylated interferon (PEG-IFN) and ribavirin have been widely discussed. Lung disorders have been described, but the respiratory function of these patients during treatment has not been well studied. The aim of this study was to investigate the incidence of dyspnoea and possible changes in lung function associated with the use of PEG-IFN and ribavirin. Methods: We evaluated clinical data and spirometry in 31 patients with chronic hepatitis C infections prior to treatment, in the 2(nd) week of treatment and in the 12(th) week of treatment. Results: During the follow-up period, 19 patients (61.3%) had dyspnoea. Decreased haemoglobin levels were observed during the study, but there was no significant association with dyspnoea. However, patients with a body mass index (BMI) greater than 25 had a higher incidence of dyspnoea. No significant difference was detected between the values of forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), or forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC) ratio measured during the investigation.
However, a significant decrease in FEV1 and FEV1/FVC ratio was observed in patients with later stages of liver fibrosis. Conclusions: Dyspnoea is a frequently occurring respiratory symptom during chronic hepatitis C treatment, and it is not associated with changes in spirometric parameters in the first 12 weeks of treatment. However, changes in FEV1 and FEV1/FVC can be observed in patients with advanced liver disease in the first 12 weeks of treatment with PEG-IFN and ribavirin.