Calculation of basal metabolic rate in patients with morbid obesity treated in spa conditions

Background The present study aimed to calculate the basal metabolic rate (BMR) with the Mifflin equation based on the expected body mass for normal body mass index (BMI) values in obese patients treated in spa conditions. Methods Patients with morbid obesity (BMI > 40 kg m(-2)) and non-obese controls (BMI < 30 kg m(-2)) were recruited. In total, 104 patients with morbid obesity (mean BMI +/- standard deviation, 46.9 +/- 2.1 kg m(-2)) treated in spa conditions and 90 non-obese controls (mean BMI, 28 +/- 1.3 kg m(-2)) were included in the present study. Results The mean BMR calculated based on actual body mass was 2088 +/- 303 kcal in patients with morbid obesity and 1424 +/- 268 kcal in non-obese controls. The BMR calculated based on expected body mass for normal BMI decreased significantly in patients with morbid obesity (p < 0.01), but not in non-obese controls. Accordingly, energy expenditure and planned caloric intake was significantly lower when BMR was calculated based on expected body mass rather than actual body mass in patients with morbid obesity, but not in non-obese controls (p < 0.01). Conclusions Expected body mass for normal BMI should be used to calculate the BMR in patients with morbid obesity.