Understanding Predictors of Fatigue Over Time in Persons With Inflammatory Bowel Disease: The Importance of Depressive and Anxiety Symptoms.

Abstract

Fatigue is a complex and frequent symptom in persons with inflammatory bowel disease (IBD), with detrimental impact. We aimed to determine predictors of fatigue over time. Two hundred forty-seven adults with IBD participated in a prospective study conducted in Manitoba, Canada, providing data at baseline and annually for 3 years. Participants reported fatigue impact (Daily Fatigue Impact Scale [DFIS]), depression and anxiety symptoms (Hospital Anxiety and Depression Scale [HADS]), and pain (Pain Effects Scale [PES]). Physician-diagnosed comorbidities, IBD characteristics, and physical and cognitive functioning were also assessed. We tested factors associated with fatigue using multivariable generalized linear models that estimated within-person and between-person effects. Most participants were women (63.2%), White (85.4%), and had Crohn's disease (62%). At baseline, 27.9% reported moderate-severe fatigue impact, 16.7% had clinically elevated anxiety (HADS-A ≥11), and 6.5% had clinically elevated depression (HADS-D ≥11). Overall fatigue burden was stable over time, although approximately half the participants showed improved or worsening fatigue impact between annual visits during the study. On multivariable analysis, participants with a one-point higher HADS-D score had, on average, a 0.63-point higher DFIS score, whereas participants with a one-point higher PES score had a 0.78-point higher DFIS score. Within individuals, a one-point increase in HADS-D scores was associated with 0.61-point higher DFIS scores, in HADS-A scores with 0.23-point higher DFIS scores, and in PES scores with 0.38-point higher DFIS scores. No other variables predicted fatigue. Anxiety, depression, and pain predicted fatigue impact over time in IBD, suggesting that targeting psychological factors and pain for intervention may lessen fatigue burden.