(P06-018-24) Validity of a Population-Specific BMR Predictive Equation in Samples of Adults From Two Different Regions of Brazil

Objectives: To verify the accuracy of local basal metabolic rate (BMR) predictive equations and the ones suggested by Schofield in two samples of adults living in the Tropics in Brazil.

Methods: A convenience sample of 100 adults living in two cities (50 in each city) from different genetic, ethnical and cultural backgrounds in Brazil (Niterói, NI, and Campo Grande, CG, 29 and 32 women, respectively) had anthropometric, BMR and body composition (BIA, Biodynamics) data collected in a visit to the laboratory. BMR was measured with a portable indirect calorimeter (Medgraphics) early in the morning with the participant lying down, after fasting for 12hrs in a quiet room with controlled temperature and humidity. Measured BMR was compared with values estimated by predictive equations: Schofield (1985) and Anjos et al. (2014). The latter were generated in a population-based survey in NI.

Results: Mean age (NI=29.7±10.6 and CG=31.7±9.5y), BM (66.6±13.7 and 70.9±17.5 kg), stature (169.8±9.7 and 167.6±7.8 cm), fat-free mass (FFM; 52.2±13.1 and 52.3±12.7 kg), and BMR (1323.7±255.2 and 1279.4±272.2 kcal.day^-1) were not significantly different between locations but fat mass was higher (p=0.004) in CG (18.5±7.8 kg) than NI (14.4±6.0 kg) in the whole group and in men (11.3±6.0 and 19.3±10.7 kg, respectively, p=0.006). BMR was higher in men (1561.6±195.4 and 1539.7±228.3 kcal.day^-1 in NI and CG, respectively) than in women (1151.3±115.9 and 1133.0±164.6 kcal.day^-1) but there was no significant statistical difference between cities for each sex and the whole group (1323.7±255.2 and 1279.4±272.2 in NI and CG, respectively; p=0.404). Schofield's BMR equations yielded significantly different values in both cities and sex (mean difference 219.5±119.8 and 290.2±179.6 kcal.day^-1 in NI and CG, and 311.0±166.2 and 219.0±138.9 kcal.day^-1 in men and women, respectively). The Anjos's BMR equations provided accurate values in both cities and sex (mean difference -25.8±110.3 and 38.0±150.8 kcal.day^-1 in NI and CG and -5.5±142.7 and 13.5±131.1 for men and women, respectively).

Conclusions: The population-specific equations generated in Brazil provide accurate BMR estimates in adults from both regions but must be validated in the other regions of the country before they be recommended for use across the country.

Funding Sources: CNPq (433760-2018-4 and 314885-2020-0)