The lack of validity of predictive equations for calculating resting energy expenditure in asian indian patients with type 1 and type 2 diabetes mellitus

Introduction: Predictive equations are used routinely to calculate resting energy expenditure and administer appropriate nutrition to patients. Validity of routinely used equations for calculating resting energy expenditure was not verified in Asian Indian population. In this study we aim to compare the predictive equations with indirectly calorimetry to test their validity in Indian population. Methods: The study included 45 male Indian subjects divided into following groups: 16 patients with Type 1 diabetes mellitus, 13 patients with Type 2 Diabetes mellitus and 16 normoglycemic subjects. All underwent anthropometric measurements, body composition measurement by DEXA scan and indirect calorimetry. REE calculated from routinely used equations and a body composition based equation was compared with REE measured by indirect calorimetry by means of Bland-Altman plot analysis. Total and mean error was also calculated for the predictive equations. Statistical analysis was done in R programming language version 3.2.4. Results: Total error of different predictive equations when compared with indirect calorimetry ranged from 375 kcal/day to 726 kcal/day across the studied groups. Bland-Altman plot analysis showed negative proportional bias i.e. equations overestimate at lower values and underestimate at higher values of measured REE. Conclusion: Routinely used predictive equations and recently introduced body composition based equation were all poor in accuracy as reflected from their high total error for estimating resting energy expenditure in Indian population when compared with indirect calorimetry. We conclude that a predictive equation for estimating resting energy expenditure must be established for use in Indian population.