Abstract P222: Sex Differences in the Association of Visceral Adiposity with Lipoprotein Subclass Analysis in Obese Adolescents
Background: Visceral adiposity contributes to metabolic syndrome in adults and children. Compared to the standard lipid panel, lipoprotein subclass particle analysis can provide additional information regarding cardiometabolic risk (CMR). The sex-specific relationships of visceral adiposity to lipoprotein subclasses have not been examined in adolescents.
Objectives: To examine the sex-specific relationships between visceral fat area and lipoprotein subclass particles and other CMR factors in obese adolescents.
Methods: This cross sectional study included obese adolescents (BMI ≥ 95th percentile for age), ages 12-18 years. Measurements included visceral fat area, as measured by dual energy x-ray absorptiometry (DXA) scan, standard lipid panel, lipoprotein subclass analysis, and homeostatic model assessment of insulin resistance (HOMA-IR). Linear regression models, adjusted for age, race, Tanner stage, and BMI were developed to evaluate associations of visceral fat area with known CMR factors. Analyses were stratified by sex to further explore the independent associations of the outcomes with visceral fat area.
Results: A total of 141 adolescents (age = 14.5 +/- 1.5 years; n = 77 (54.6%) female (F); n = 123 (87.2%) African-American) with mean BMI = 35.2 +/- 6.4 kg/m2 were included. Visceral fat was negatively associated with LDL particle (-P) size (p=0.0002), large LDL-P concentration (p=0.03), HDL-P size (p<0.0001) and large HDL-P concentration (p<0.0001) while being positively associated with small LDL-P concentration (p=0.0006), small HDL-P concentration (p=0.021), and a marginal positive association with total LDL-P (p=0.075). Visceral fat was also negatively associated with HDL cholesterol (-C) (p=0.0003) and positively associated with triglycerides (TG) (p=0.0021), TG/HDL-C ratio (p=0.0001), and HOMA-IR (p=0.0008). There was no association found with LDL-C (p=0.57). When stratified by sex (female=F, male=M), the associations of visceral fat with LDL-P size (F: p=0.0002, M: p=0.38), small LDL-P concentration (F: p=0.0001, M: p=0.56), and large LDL-P concentration (F: p=0.08, M: p=0.75) persisted only for females. In contrast, the association between visceral fat and small HDL-P concentration was significant only in males (M: p=0.012, F: p=0.50).
Conclusion: In a cohort of largely African American obese adolescents, visceral adiposity is associated with increased cardiometabolic risk and a more atherogenic lipoprotein subclass profile even after adjusting for BMI. The relationships between visceral fat area and certain lipoprotein subclasses are significantly different in males versus females. These findings suggest visceral adiposity provides additional sex-specific information beyond BMI alone.
Author Disclosures: J.A. Hatch-Stein: None. A. Kelly: None. S.S. Gidding: None. B.S. Zemel: None. S.N. Magge: None.
- © 2015 by American Heart Association, Inc.