Els van de Vijver

121 Table 1 | Identification of factors contributing to IBD-associated fatigue. Adult studies printed in grey Predictors of fatigue Effect on fatigue Aggravation Alleviation Biological factors Disease activity Compared to patients with quiescent disease, adolescents with active disease have impaired physical wellbeing and more trouble sleeping (15) IBD adolescents are more tired in case of active disease (16) Effective induction and maintenance therapy Medication Use of corticosteroids, thiopurines, and anti-TNF agents are associated with more fatigue (17-19) Anti-inflammatory management. (20, 21) Haematological factors Iron deficiency anaemia(22) iron supplements or intravenous iron therapy Psychobehavioral factors Family support Family dysfunction (23) Maternal positive affect (23) Psychological factors Depression and anxiety (24) Mindfulness and relaxation (25) Cognitive behavioural therapy (25, 26) Functional factors Physical activity Impairment in motor functioning(27) Decreased physical exercise (28) Physical training reduces fatigue in postoperative IBD patients(29) In Chapter 6 we assessed the relationship between biological and functional factors and IBD-associated fatigue. We evaluated haemoglobin, iron status, calprotectin (as marker of intestinal inflammation), disease-specific quality-of-life (with the IMPACT-III questionnaire) and physical fitness (by 6 minute walking distance, 6MWD) in children with quiescent, mild or moderate IBD. Using the PedsQL TM multidimensional fatigue scale, participating children with IBD were classified as fatigued or non-fatigued. We found no differences between the fatigued or non-fatigued groups in terms of haemoglobin concentration, faecal calprotectin, and ferritin concentration. The mean 6MWD in the cohort of paediatric IBD patients was 1 standard deviation below age-related healthy controls, but the mean 6MWD in the fatigued and non-fatigued IBD patients was not significantly different. The quality-of-life score was inversely related to fatigue: the more fatigued, the lower the quality-of-life score. General discussion 121