Abstract
AIM: To investigate the impact of chronic fatigue on disease-related worries in inflammatory bowel disease (IBD) and the potential multicolinearity between subjective questionnaires. METHODS: Patients in remission or with mild-to-moderate disease activity completed the fatigue questionnaire (FQ), the rating form of IBD patient concerns (RFIPC), the Short-Form 36 (SF-36), and IBD questionnaire (N-IBDQ). In addition, clinical and epidemiological data were obtained. RESULTS: In total, 140 patients were included; of which 92 were diagnosed with ulcerative colitis and 48 with Crohn's disease. The mean age of patients with chronic fatigue was 44.2 years (SD = 15.8) and for non-fatigued patients was 44.7 years (SD = 16.0). Chronic fatigued patients had clinically significantly increased levels of disease-related worries, as measured by Cohen's d effect size. Worries about having an ostomy bag, loss of bowel control, and energy levels were most prominent in both chronic fatigued and non-chronic fatigued IBD patients. Variance inflation factor (VIF) and tolerance indicated that there were no problematic multicolinearity among the FQ, RFIPC, SF-36 and N-IBDQ responses (VIF < 5 and tolerance > 2). CONCLUSION: Chronic fatigue is associated with increased levels of disease-related worries and concerns in IBD. Increased levels of worries were also associated with impaired health-related quality of life.