1782-P: Association of Body Fat Distribution with Insulin Resistance and Inflammation in Lean vs. Obese Individuals

Introduction and Objective: Metabolic abnormalities are present in 15-25% of lean adults (BMI <25 kg/m2). Prior studies have shown differences between metabolically unhealthy lean (MUL) and metabolically unhealthy obese (MUO) (BMI >30 kg/m2) adults, with increased android fat in MUL and decreased gynoid fat in MUO when compared to the corresponding healthy groups. In this study, we evaluated the association of fat distribution with insulin resistance (IR) and inflammation in the lean and obese populations. Methods: We used data from the NHANES database (2011-2018) including DXA measures of body fat distribution. HOMA-IR was calculated from fasting glucose and insulin levels. High sensitivity CRP was used as an index of inflammation. Participants with incomplete data, presence of diabetes or CRP >10 mg/L were excluded. Univariate and multivariate regression analyses were performed. Results: The lean group included 1690 adults for HOMA-IR and 633 for CRP data analysis. The obese group included 1398 adults for HOMA-IR and 572 for CRP data analysis. In a multivariate regression analysis within the lean group, android fat (beta=0.338, p<0.001), gynoid fat (beta=-0.455, p<0.001) and total fat (beta=0.351, p=0.010) were all independent predictors of HOMA. However, android fat was the only independent predictor of CRP (beta=0.255, p=0.012) in the lean group. On multivariate regression analysis within the obese group, android fat (beta=0.247, p=<0.001), gynoid fat (beta=-0.898, p=<0.001) and total fat (beta=0.638, p=<0.001) were again independent predictors of HOMA. However, gynoid fat (beta=-0.686, p=<0.001) and total fat (beta=0.925, p<0.001) were independent predictors of CRP, and android fat was not an independent predictor of CRP in the obese group. Conclusion: This study shows increased visceral fat is the major contributor to metabolic abnormalities in lean adults while increased total fat and decreased gynoid fat are the major contributors in obese adults. Disclosure S. Anand: None. T. Pasupneti: None. R.K. Garg: None.