Estimating resting energy expenditure of patients on dialysis: Development and validation of a predictive equation

Abstract Objectives The aims of this study were to develop and validate a resting energy expenditure (REE) predictive equation in a cohort of patients on dialysis and to test the accuracy of two previously developed specific equations to estimate REE of these patients. Methodology A database with REE measured by indirect calorimetry (IC) of 189 patients on hemodialysis and peritoneal dialysis was used to develop and to validate the new equation. The sample including only hemodialysis patients (n=131) was used to test the accuracy of the specific REE dialysis equations by Vilar and Byham-Gray. Results Multiple regression analysis generated two equations: REE (kcal/day) = 957.02 - 8.08 x age + 11.07 x body weight + 136.4 (if men) (R 2  = 0.515) and REE (kcal/day) = 624.6 – 4.8 x age + 20.6 x Fat Free Mass – 8.65 (if men) (R 2  = 0.512). In the validation group, REE by both equations did not differ from the REE measured by IC. No bias was found in the Bland-Altman analysis and the intraclass correlation coefficient and P20 test showed good reliability with measured REE. Vilar's equation overestimated REE while REE generated by Byham-Gray's equation did not differ from measured REE. Proportional and systematic biases were significant for both equations. Conclusions The new equations developed showed good accuracy and can be valuable to estimate energy needs of patients on dialysis. Byham-Gray´s and Vilar´s equations presented low to moderate performance to estimate REE of our dialysis patients.