Factors Associated with Physical and Cognitive Fatigue in Patients With Crohn's Disease: A Cross-sectional and Longitudinal Study

Background:Fatigue commonly impairs quality of life in patients with Crohn's disease (CD). This study aimed to evaluate the prevalence and severity of fatigue in CD (compared with ulcerative colitis [UC] and healthy controls) and to identify potentially modifiable factors associated with global, physical, and cognitive dimensions of fatigue.Methods:Clinic attendees with confirmed CD or UC and healthy volunteers were surveyed on fatigue (Fatigue Impact Scale, FIS), psychological comorbidity, sleep quality, medication, and other clinical information. A CD subgroup also completed a similar follow-up survey.Results:In 379 responders (181 CD, 113 UC, and 85 controls), global, physical, and cognitive FIS scores were highest in CD followed by UC and controls (P < 0.01), with a prevalence of global fatigue (total FIS 40) in 57% of CD patients. On multivariate analysis, concurrently active disease, poor sleep quality, and mental illness were significantly associated with all the 3 fatigue dimensions: regular vitamin B group supplementation was inversely associated with physical fatigue in the CD cohort and those of older age or with previous resection(s) (P = 0.05) were independently associated with cognitive fatigue only. Longitudinally in CD, fatigue scores remained constant between original and follow-up surveys (mean change in total FIS score +0.9; 95% confidence interval, -4.6 to 6.3). Factors independently associated with improved physical fatigue between surveys included avoidance of corticosteroids and establishment of regular exercise and with improved cognitive fatigue included cessation of immunomodulator therapy.Conclusions:Fatigue is highly prevalent and more severe in CD. Anticipated and novel associations with improvement of physical and/or cognitive fatigue were identified, offering clues to potential therapeutic approaches to ameliorating fatigue for clinical evaluation.