Obesity is a well-established risk factor for type 2 diabetes (T2D) in youth. However, the contribution that organ fat plays to the pathophysiology of T2D among high-risk youth is sparsely documented. The purpose of this study was to determine the independent associations between hepatic and pancreatic fat fractions with insulin sensitivity and beta-cell function among Latino youth with obesity and prediabetes. This cross-sectional analysis involved 117 Latino adolescent boys (n=70) and girls (n=47), mean (±SD) age:14±1 years, fasting glucose: 102±8mg/dL, 2-hour glucose: 144±30mg/dL, and with obesity (BMI percentile: 98.52±1.13). Total body composition was assessed by DEXA, while hepatic and pancreatic fat contents were assessed using quantitative fat fraction magnetic resonance imaging at 3 Tesla. T2D risk factors included insulin sensitivity (Matsuda index) and beta-cell function (product of insulin sensitivity and insulinogenic index), estimated from a multi-sample 2-hour oral glucose tolerance test. Associations between organ fat and T2D risk factors were examined using Pearson correlation and multiple linear regression, adjusting for age, sex, and total body fat percentage (BF%). Insulin sensitivity significantly correlated with only BF% (r =-0.236, p=0.015), fat mass (r=-0.227, p=0.020), and hepatic fat fraction (r=-0.255, p=0.024), whereas beta-cell function significantly correlated with only BF% (r=-0.241, p=0.013). In multiple regression models, hepatic fat fraction (B= -0.045, p=0.041, Δr2=.034) but not pancreatic fat fraction (B= 0.058, p=0.179, Δr2= .015) was independently associated with insulin sensitivity, whereas neither measure of organ fat was associated with beta-cell function (each Δr2<.01, each p>.38). Hepatic fat content was an independent predictor of insulin sensitivity among Latino youth with prediabetes. Further studies are needed to understand how adiposity contributes to beta-cell dysfunction among high-risk youth.
E.O.Owolabi: None. M.Olson: Advisory Panel; Rhythm Pharmaceuticals, Inc. H.H.Hu: None. A.Pena: None. K.A.Pituch: None. S.Bailey: None. W.C.Knowler: None. G.Q.Shaibi: None.
National Institute of Diabetes and Digestive and Kidney Diseases (R01DK107579, F31DK125037)