Fatigue Trajectory During the First Year of an Inflammatory Bowel Disease Diagnosis, Results from the IBSEN III study

BACKGROUND: Fatigue is common in Crohn's disease (CD) and ulcerative colitis (UC), but the pathogenesis remains poorly understood. AIMS: This study aimed to assess changes in fatigue prevalence during the first year after diagnosis and examine the association between disease course and substantial fatigue (SF) at the 1-year follow-up. METHODS: Adults with newly diagnosed CD or UC were recruited from the population-based IBSEN III cohort. Fatigue was assessed at diagnosis and the 1-year follow-up using the Fatigue Questionnaire. Associations between SF at the 1-year follow-up and disease-related factors were quantified using multivariate logistic regression adjusted for sex, age and comorbidities. RESULTS: In total, 596 patients were included (CD: 196, UC: 400). SF was present at both baseline and after one year of disease for 46.9% (n = 92/196) and 40.5% (n = 162/400) of patients with CD and UC, respectively. In CD, development of endoscopically non-passable stricture and/or surgically treated stricture within first year of disease (OR = 4.52, 95%CI [1.61;12.68]), self-reported flares since diagnosis (OR = 2.55, 95%CI [1.26;5.16]), female sex (OR = 3.12, 95%CI [1.53;6.37]) and comorbidities (OR = 4.05, 95%CI [1.89;8.69]) were independently associated with SF at the 1-year follow-up. In UC, SF was associated with current biological treatment (OR = 5.14, 95%CI [1.56;16.96]), increasing Mayo endoscopic score at the 1-year follow-up (OR = 1.54, 95%CI [1.01;2.35]), self-reported flares since diagnosis (OR = 2.66, 95%CI [1.24;5.72]) and female sex (OR = 2.20, 95%CI [1.06;4.57]). CONCLUSIONS: Fatigue frequently persists through the first year after IBD diagnosis. Clinical factors reflecting a more severe disease course were associated with SF one year after diagnosis in both CD and UC.