Can We Rely on Resting Metabolic Rate Equations? Large Variance in Crohn Disease Pediatric Patients

Inadequate caloric intake is common in Crohn disease (CD) and nutrition support plays an important role in remission induction and in meeting nutritional needs. For nutritional planning, determining resting metabolic rate (RMR) is essential in pediatric patients with CD.

To measure RMR in CD pediatric patients using indirect calorimetry, and compare it with estimated RMR (eRMR) calculated by Schofield equation.

Children with CD treated in a tertiary pediatric inflammatory bowel disease center in Israel participated in the cross-sectional study. At study visits, weight, height, clinical and laboratory assessments, bioelectrical impedance, and RMR measured by indirect calorimetry were done. Additionally, disease severity was determined by the Pediatric Crohn Disease Activity Index and eRMR was calculated using the Schofield equation. The ratio of the measured RMR to eRMR was performed in addition to the Spearman correlation test.

The study group included 73 children (49 boys) with mean age of 13.9 ± 2.3 years. Children with moderate or severe disease had lower weight for age z score, lower BMI- z , and lower RMR compared to children with mild disease. However, when RMR was adjusted for fat free mass (n = 50), the association between RMR and disease severity disappeared. Variance in RMR was high between subjects.

Our data suggest that the Schofield equation is inadequate for determining RMR in pediatric CD and that RMR should be measured to guarantee the most appropriate nutritional intervention.