Equations for the prediction of resting energy expenditure in chronic obstructive lung disease.

Resting energy expenditure can be obtained either by indirect calorimetry or from prediction equations. Several prediction equations were compared to the measured value of REE in a group of COPD patients with moderate to severe disease. Then, using the same group of patients, a new equation was derived by regression analysis and was prospectively tested on patients with similar characteristics. Equations derived from normal populations (Harris-Benedict, Wilmore nomogram) were shown to underestimate REE by 300-400 Kcal. Equations that use body weight as the only variable were found to be easier to use and did not appear to sacrifice accuracy. Quebbeman Ausman body weight, Quebbeman Ausman body surface area and a regression equation derived from COPD patients (males, REE = 11.5 x wt [kg] + 952; females, REE = 14.1 x wt [kg] + 515) performed better than other currently used equations. In both stable COPD and COPD with exacerbation, the mean predicted values fell within a standard deviation (+/- 167 Kcal) of measured values.