Resting metabolic rate in severely obese diabetic and nondiabetic subjects.

Abstract

To compare the resting metabolic rate (RMR) between diabetic and nondiabetic obese subjects and to develop a predictive equation of RMR for these subjects. Obese adults (1088; mean age = 44.9 +/- 12.7 years) with BMI > or = 35 kg/m2 (mean BMI = 46.4 +/- 8.4 kg/m2) were recruited. One hundred forty-two subjects (61 men, 81 women) were diagnosed with type 2 diabetes (DM), giving the prevalence of DM in this clinic population as 13.7%. RMR was measured by indirect calorimetry, and several multivariate linear regression models were performed using age, gender, weight, height, BMI, fat mass, fat mass percentage, and fat-free mass as independent variables. The severely obese patients with DM had consistently higher RMR after adjustment for all other variables. The best predictive equation for the severely obese was RMR = 71.767 - 2.337 x age + 257.293 x gender (women = 0 and men = 1) + 9.996 x weight (in kilograms) + 4.132 x height (in centimeters) + 145.959 x DM (nondiabetic = 0 and diabetic = 1). The age, weight, and height-adjusted least square means of RMR between diabetic and nondiabetic groups were significantly different in both genders. Severely obese patients with type 2 diabetes had higher RMR than those without diabetes. The RMR of severely obese subjects was best predicted by an equation using age, gender, weight, height, and DM as variables.