Disease Activity Is Associated with Obesity in Newly Diagnosed Pediatric Patients with Ulcerative Colitis

Malnutrition and inflammatory bowel disease (IBD) are interrelated conditions. Our aim was to assess the prevalence of malnutrition, to compare anthropometric parameters in the evaluation of nutritional status in pediatric IBD, and to investigate the association between anthropometric parameters and disease activity indices (AI). Pediatric patients with newly diagnosed IBD recorded between 2010 and 2016 in the Hungarian Pediatric IBD Registry were included in this cross-sectional study. Body weight, body mass index (BMI), weight-for-height, and ideal body weight percent (IBW%) were analyzed. Pearson linear and non-linear correlations and polynomial regression analyses were performed to assess correlation between nutritional status and AI. p-values < 0.05 were considered significant. Anthropometric data of 1027 children with IBD (Crohn’s disease (CD): 699; ulcerative colitis (UC): 328; mean age 13.7 years) were analyzed. IBW% identified more obese patients than BMI both in CD (7.02% vs. 2.28%) and UC (12.17% vs. 5.48%). Significant negative correlation was found among anthropometric parameters and AI in CD. In contrast, polynomial regression analysis revealed a U-shaped correlation curve between IBW% and AI in UC. Our findings show that obesity has a bimodal association with disease activity in pediatric UC. Furthermore, IBW% was more useful to identify obese pediatric patients with IBD.