Relative impact of fatigue and subclinical cognitive brain dysfunction on health-related quality of life in chronic hepatitis C infection

To assess the relative impact of fatigue and subclinical cognitive brain dysfunction on the impairment of health-related quality of life (HRQL) in hepatitis C virus (HCV) infection. We performed a cross-sectional study in 120 patients with untreated chronic HCV infection to test the hypothesis that the severity of fatigue had an independent effect on HCV-associated impairment of HRQL. Patients were investigated using the short-form-36 questionnaire, the fatigue impact scale, the brief fatigue inventory, and P300 event-related potentials, as an objective correlate of neurocognitive function. Patients with decompensated cirrhosis or clinical depression were excluded. Relative to healthy controls, HCV-infected patients showed significant levels of fatigue (Fatigue Impact Scale, 49 versus 26 points, brief fatigue inventory, 3.0 versus 1.6 points, P < 0.001). Fatigue impact scale and brief fatigue inventory scores were highly correlated (r = 0.77, P < 0.001), demonstrating concurrent validity. Severity of fatigue and age were the only factors independently associated with the impairment of HRQL (P < 0.001). Fatigue was not related to the severity of hepatitis or the degree of subclinical brain dysfunction. In untreated patients with chronic HCV infection, fatigue severity and age but not neurocognitive dysfunction or hepatic function are independently associated with impaired HRQL. Both the fatigue impact scale and the brief fatigue inventory are suitable tools to assess the subjective burden of fatigue. Our findings stress the need for effective therapeutic interventions to reduce the burden of fatigue in patients with HCV infection.