Body composition, physical activity, and quality of life in pediatric patients with inflammatory bowel disease on anti-TNF therapy—an observational follow-up study

Background: Poor outcome of inflammatory bowel disease (IBD) is associated with malnutrition. The aim was to compare body composition (BC) and physical activity (PA) between pediatric IBD patients and healthy controls, and to assess changes in BC, PA, and health-related quality of life (HRQoL) during anti-TNF therapy. Methods: In this prospective observational study, 32 children with IBD (21 Crohn’s disease [CD], mean age 15.2 ± 2.6 years; 11 ulcerative colitis [UC], mean age 16.4 ± 2.2 years) and 307 healthy controls (mean age 14.3 ± 2.1 years) were included. BC was assessed via bioelectric impedance, PA and HRQoL via validated questionnaires at initiation of anti-TNF therapy and at 2 and 6 months. General linear model and Friedman test were used to track changes. Results: In CD, fat-free mass (FFM) Z score increased significantly over follow-up (−0.3 to 0.1, p = 0.04); BC parameters in UC did not change. PA in CD was lower than in controls at baseline (1.1 vs 2.4), but the difference disappeared by 6 months. Conclusions: FFM and PA increased in CD during the first six months of anti-TNF treatment. Given the impact of malnutrition and inactivity during critical developmental periods, promoting PA and monitoring nutritional status should be emphasized in pediatric IBD care.