Resting energy expenditures measured by indirect calorimetry are higher in preadolescent children with cystic fibrosis than expenditures calculated from prediction equations.

OBJECTIVE

This study compared measured resting energy expenditures to resting energy expenditures calculated using Harris-Benedict equations (HBEs) and the Cystic Fibrosis Consensus Committee equations (CFCCEs).

DESIGN

We studied 31 preadolescent boys and girls with cystic fibrosis who ranged in age from 3.25 to 12.75 years old. The patients were afebrile and not in pulmonary distress. Measured resting energy expenditures were determined using a portable metabolic measurement cart with fully automated calibration and data management. The measured resting energy expenditures obtained were compared with values obtained using HBEs and CFCCEs.

RESULTS

For each patient, the measured resting energy expenditure value was above the predicted resting energy expenditure values derived from HBEs (P < or = .0001) and CFCCEs (P < or = .01).

APPLICATIONS

The HBEs and the CFCCEs underestimated the energy expenditures of the study population by 13% and 8%, respectively. These findings support the usefulness of the measurement of energy expenditures in determining the energy needs of preadolescent patients with cystic fibrosis. In clinical practice, the resting energy expenditures would be multiplied by activity coefficients to determine the total daily energy expenditures of this population.