Fatigue in patients with inflammatory bowel disease in remission one year after diagnosis (the IBSEN III study).

Background and aims: Fatigue is commonly observed in Crohn's disease (CD) and ulcerative colitis (UC), but its association to achieving remission is not clearly established. In this study we describe the odds for fatigue in patients with CD/UC one year after diagnosis based on different definitions of remission and identified factors associated with chronic fatigue (CF) among patients in endoscopic/radiological remission.

Methods: Patients ≥18 years with CD/UC were recruited from the IBSEN III cohort. Using the Fatigue Questionnaire, and dichotomizing the score, CF was defined as the presence of substantial fatigue (SF) for ≥6 months. Remission was divided into symptomatic (CD: HBI score<5/UC: SCCAI score<3), biochemical (faecal calprotectin ≤250µg/g), endoscopic/radiological (CD: normal intestinal MRI/CT combined with normal endoscopy/UC: Mayo endoscopic score 0) and histological (normal mucosal biopsies). Both the likelihood of SF/CF, depending on the definition of remission, and associations between CF and selected factors for CD/UC in endoscopic/radiological remission, were evaluated using binary logistic regression analysis.

Results: In total, 711/1416 patients were included. For both CD and UC, symptomatic remission significantly reduced the odds for SF and CF. Additionally, the odds for SF were significantly reduced for UC in biochemical remission. Among those in endoscopic/radiological remission (n=181), CF was independently associated with sleep disturbances (OR=10.40, 95%CI [3.28;32.99], p<0.001) and current treatment with infliximab (OR=4.31, 95%CI [1.15;16.17], p=0.03).

Conclusions: Stricter definitions of disease remission were not associated with a decreased likelihood of fatigue. For patients in endoscopic/radiological remission, CF was independently associated with sleep disturbances and current treatment with infliximab.