The true impact of fatigue in primary biliary cirrhosis: a population study

Patient surveys suggest that fatigue is a common problem in primary biliary cirrhosis (PBC). The actual extent of the problems caused by fatigue in PBC has yet to be determined as previous studies addressing this question have tended to use selected patient subgroups and subjective or non-quantitative fatigue assessment tools. Here, we have attempted to more accurately assess the extent of fatigue in PBC, and the specificity of the symptom for this disease, by the application of an objective measure of fatigue impact (the fatigue impact score [FIS]) to a geographically based patient cohort, age- and sex-matched normal controls, and chronic liver disease controls.

Postal completion of the FIS and linked symptom assessment tools.

Median FIS was significantly higher in patients (n = 136) than community controls (40 [0-138] vs. 28 [0-156]; P < 0.0001) and chronic liver disease controls (n = 38) (20.5 [0-145]; P < 0.05). Fatigue scores in the 11 patients who had undergone liver transplantation (median 3.5 years previously) were the same as those in non-transplanted patients with advanced disease.

Fatigue is a significant and specific problem in PBC. It is not, however, universal and affects fewer patients than has previously been thought to be the case based on data from selected patient cohorts. This definition of the "normal range" for fatigue in PBC will assist in future studies of etiology and therapy.