Sex and Body Circumferences Associated with Serum Leptin in African American Adults

Objective: Cardiovascular disease (CVD) continues to be a leading cause of death for U.S. adults, especially African Americans (AA). Yet, few studies have examined a comprehensive set of metabolic health and health behavior factors related to CVD risk in this population. This study investigated the relationship between serum leptin and anthropometries (body mass index [BMI], circumferences [waist-WC, hip-HC, and waist/hip ratio W/H]), metabolic health (systolic and diastolic blood pressure [BP], serum lipids, glucose, and C-reactive protein [CRP]), and health behaviors (hours of sleep, physical activity) in midlife and older AAs. Materials and Methods: Participants (n = 89, >= 45 years of age) were AAs in six churches in North Florida enrolled in a broader church-based longitudinal study. Anthropometric measurements, serum analyses, and self-reported items. Results: Serum leptin was positively correlated with gender (being female) (r = 0.623, p < 0.001), BMI log transformed (r = 0.469, p < 0.001), WC (r = 0.440, p < 0.001), HC (r = 0.658, p < 0.001), use of BP medication (r = 0.216, p < 0.05), and serum CRP (r = 0.277, p < 0.01). Correlations by sex showed significant relationships for both men and women between leptin and BMI log transformed, WC, and HC. The final multiple regression model [R-2 = 0.758, F(4, 66) = 55.871, p < 0.001] showed that 75.8% of the variance in leptin was explained by being female (beta = 0.65, p < 0.001), WC (beta = 0.26, p < 0.02), and HC (beta = 0.28, p < 0.01). Conclusions: Findings more specifically delineate the variables associated with serum leptin in AAs, particularly WC and HC, and suggest greater attention to possible risk for leptin resistance in AA females. Clinical Trial Registration: This study is registered at www.clinicaltrials.gov NCT03339050.

Automated summary

This study found that serum leptin in midlife and older African Americans is closely related to factors such as gender, body mass index, waist circumference, hip circumference, with a particular emphasis on females. Greater attention is needed for potential leptin resistance risk in African American females.