Relationship of leptin, resting metabolic rate, and body composition in pre-menopausal Hispanic and non-Hispanic White women
Abstract
Understanding metabolic and hormonal influences on energy expenditure among pre-menopausal women may help discern factors that influence racial/ethnic disparities in overweight and obesity among women. Purpose. To evaluate the relationship between fasting serum leptin, resting metabolic rate (RMR), and body composition in pre-menopausal Hispanic and non-Hispanic White (White) women. Methods. Participants were 67 Hispanic [mean ± SE age: 42.8 ± 0.6 y; ht: 161.5 ± 0.6 cm; mass: 69.7 ± 1.8 kg; BMI: 26.7 ± 0.7 kg/m2] and 43 White [age: 43.4 ± 0.6 y; ht: 165.5 ± 1.0 cm; mass: 66.6 ± 1.9 kg; BMI: 24.3 ± 0.6 kg/m2] women. Participants arrived at the lab in a fasted state for measurement of RMR by indirect calorimetry. Bone mineral content was measured by DXA and body density was determined by hydrodensitometry. Percentage of body fat was estimated using a 3-compartment equation (Lohman, 1986). Serum leptin levels were determined by EIA. Results. Overall, a strong correlation was observed between leptin and fat mass (FM) (r = 0.51; P < 0.001). When separated by race, Hispanics showed a strong correlation (r = 0.62; P < 0.001), while Whites showed a weak correlation (r = 0.16; P > 0.05) between leptin and FM. There was a moderate correlation between leptin and RMR (r = 0.36; P < 0.001) for both groups combined. Hispanic women demonstrated a moderate correlation (r = 0.47; P < 0.001), while White women demonstrated no correlation (r = 0.07; P > 0.05) between leptin and RMR. There was a high correlation (r = 0.71; P < 0.001) between RMR and lean body mass (LBM) for both groups combined. Independently, both Hispanics and Whites showed a strong correlation (r = 0.70, 0.76, respectively; P < 0.001) between RMR and LBM. Multiple regression analysis revealed that body mass and LBM were the best predictors of RMR. Leptin was not a significant predictor of RMR. Conclusion. These data indicate that leptin was not a predictor of RMR in pre-menopausal Hispanic women. However, body mass and LBM was associated with RMR for both Hispanic and White women. Further research examining the relationship between leptin and energy expenditure is needed.
Subject Area
Physiology
Recommended Citation
Deemer, Sarah E, "Relationship of leptin, resting metabolic rate, and body composition in pre-menopausal Hispanic and non-Hispanic White women" (2008). ETD Collection for University of Texas, El Paso. AAI1453838.
https://scholarworks.utep.edu/dissertations/AAI1453838