Resting energy expenditure in children with inflammatory bowel disease.
OBJECTIVE
There is controversy in the literature regarding the effect of inflammatory bowel disease (IBD) on resting energy expenditure (REE). In many cases this may have resulted from inappropriate adjustment of REE measurements to account for differences in body composition. This article considers how to appropriately adjust measurements of REE for differences in body composition between individuals with IBD.


METHODS
Body composition, assessed via total body potassium to yield a measure of body cell mass (BCM), and REE measurements were performed in 41 children with Crohn disease and ulcerative colitis in the Royal Children's Hospital, Brisbane, Australia. Log-log regression was used to determine the power function to which BCM should be raised to appropriately adjust REE to account for differences in body composition between children.


RESULTS
The appropriate value to "adjust" BCM was found to be 0.49, with a standard error of 0.10.


CONCLUSIONS
Clearly, there is a need to adjust for differences in body composition, or at the very least body weight, in metabolic studies in children with IBD. We suggest that raising BCM to the power of 0.5 is both a numerically convenient and a statistically valid way of achieving this aim. Under circumstances in which the measurement of BCM is not available, raising body weight to the power of 0.5 remains appropriate. The important issue of whether REE is changed in cases of IBD can then be appropriately addressed.
Hill
R J
RJ
Children's Nutrition Research Centre, Discipline of Paediatrics and Child Health, University of Queensland, Royal Children's Hospital, Herston, Australia. rj.hill@uq.edu.au
Cleghorn
G J
GJ
Withers
G D
GD
Lewindon
P J
PJ
Ee
L C
LC
Connor
F
F
Davies
P S W
PS
D000293:Adolescent; D001481:Basal Metabolism / Q000502:physiology*; D001823:Body Composition; D001835:Body Weight / Q000502:physiology; D002648:Child; D004734:Energy Metabolism / Q000502:physiology*; D005260:Female; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000378:metabolism*; D008297:Male; D008433:Mathematics; D009751:Nutritional Requirements; D009752:Nutritional Status; D011197:Potassium Radioisotopes / Q000032:analysis; D012044:Regression Analysis
D011197:Potassium Radioisotopes