Evaluation of fatigue in U.S. patients with primary biliary cirrhosis

OBJECTIVES: Fatigue, which may have a significant impact on quality of life, is the most common reported symptom in primary biliary cirrhosis (PBC). Multiple instruments to quantify fatigue and quality of life in liver disease have been validated, but have not been broadly applied to U.S. PBC patients. This study examines the extent of fatigue and its effect on quality of life in U.S. PBC patients. METHODS: Seventy patients with PBC were administered two validated questionnaires about quality of life (the Mayo version of the NIDDK-QA) and fatigue (the Fisk Fatigue Impact Score) and a proposed physical measure of fatigue in PBC (the grip strength test) on the day of routine physician visit. Nonparametric methods were employed. RESULTS: The fatigue and quality of life domain scores (physical functioning, liver symptoms, health satisfaction, Karnofsky index) discriminated between patients with and without self-reported fatigue (p < 0.05), as opposed to the grip strength results. Fatigue and quality of life domains correlated strongly with each other (r between 0.33 and 0.74, p ≤ 0.006) and not with the grip strength results. Neither quality of life nor fatigue scores correlated with age. CONCLUSIONS: The correlation between fatigue and quality of life scores suggests fatigue has an impact on quality of life in U.S. primary biliary cirrhosis patients. However, our fatigue scores suggest U.S. PBC patients have less fatigue than non-U.S. PBC patients. The grip strength is an insensitive measure of fatigue in U.S. PBC patients.