Evaluation of formulas for calculating total energy requirements of preadolescent children with cystic fibrosis.
BACKGROUND
To support age-appropriate growth and to prevent and treat malnutrition in children with cystic fibrosis (CF), energy requirements for those children are often set above the requirements for healthy children. Care providers use one of several empirically derived formulas to calculate energy requirements, yet the validity of these formulas has seldom been tested.


OBJECTIVE
We evaluated 6 proposed formulas for calculating energy requirements in children with CF against a total energy requirement for children with CF (TER-CF) derived from measured total energy expenditure, fecal fat energy loss, and the theoretic energy required for age-appropriate tissue accretion.


METHODS
Subjects were children aged 6-8 y who had CF and pancreatic insufficiency. Calculated TERs from each formula were evaluated against TER-CF by using summary statistics, regression analysis, and residual plots.


RESULTS
Subjects (n = 53) had suboptimal nutrition and growth status and mild-to-moderate lung disease. The formula that most closely (within 2%) approximated TER-CF was the estimated energy requirement (EER) formula at the active level (EERact). Regression analysis of TER-CF onto calculated TER from each formula yielded the best indexes of model fit for the EERact formula; residual plots of the EERact formula were tightly and normally distributed around zero.


CONCLUSIONS
The EERact formula should be used to establish TER-CF in children in this age group who have mild-to-moderate CF. Changes in weight, height, and other indicators of nutritional status must be monitored to modify TER-CF as needed to support individual patient care goals.
Trabulsi
Jillian
J
Divisions of Gastroenterology, Hepatology, and Nutrition, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
Ittenbach
Richard F
RF
Schall
Joan I
JI
Olsen
Irene E
IE
Yudkoff
Marc
M
Daikhin
Yevgeny
Y
Zemel
Babette S
BS
Stallings
Virginia A
VA
D000886:Anthropometry; D002648:Child; D002657:Child Development; D003550:Cystic Fibrosis / Q000150:complications / Q000378:metabolism / Q000628:therapy*; D002149:Energy Intake / Q000502:physiology; D004734:Energy Metabolism / Q000502:physiology; D010188:Exocrine Pancreatic Insufficiency / Q000150:complications / Q000378:metabolism / Q000628:therapy*; D005243:Feces / Q000737:chemistry; D005260:Female; D005526:Food, Formulated; D006128:Growth / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D007408:Intestinal Absorption; D008137:Longitudinal Studies; D008297:Male; D015596:Nutrition Assessment; D009751:Nutritional Requirements; D009752:Nutritional Status; D015430:Weight Gain / Q000187:drug effects* / Q000502:physiology