OR15-06 Measuring Hepatic Steatosis With Transient Elastography In Adolescents With Obesity

Disclosure: D. Sundararajan: None. J.S. Lo: None. N. Morelli: None. Y. Garcia-Reyes: None. M.A. Ware: None. H. Rahat: None. S. Sundaram: None. C. Severn: None. L.L. Pyle: None. E. Tas: None. M.G. Cree: Consulting Fee; Self; Pollie, Inc. Research Investigator; Self; Amino Corp. Obesity affects nearly 20% of adolescents in the United States. Nonalcoholic fatty liver disease (NAFLD) is a common comorbidity, affecting between 40-70% of youth with obesity, thus approximately 10% of United States youth. Traditional diagnostic methods for NAFLD are expensive or invasive, and recently, transient elastography has been used to diagnose hepatic steatosis (HS). We sought to determine if transient elastography accurately diagnosed HS as compared to MRI in adolescents with obesity. Baseline data from adolescents (age 12-18 years) with obesity studied in 3 clinical trials were included (NCT03919929, NCT03717935, NCT04342390). Liver fat was assessed with 2 methods: MRI proton density fat fraction and transient elastography controlled attenuation parameter (CAP) score. Demographics, anthropometrics, liver scans and fasting serum laboratory measures were collected. HS was defined as MRI fat fraction ≥ 5.0%. Group data means, standard deviation, and ranges were calculated, and CAP for those with and without HS by MRI were compared with Mann Whitney U tests. Receiver operator curves (ROC) for CAP were generated based on MRI-determined HS. Data from 84 adolescents (age 15.6 ± 1.4 years, BMI 36.5 ± 5.96 kg/m2, 81% female) were included. Fifty-one had HS by MRI, with liver fat % different by HS status [9.3 (6.7, 14.0)% HS vs 3.1 (2.2, 3.9); p < 0.001]. CAP scores were different by MRI based on HS status [293 (267, 325) HS vs 267 (248, 282); p = 0.012]. With the recommended CAP cutoff for HS of 241, there was only a 59% concordance of HS status between the MRI and CAP. For CAP, ROC for HS was significant (r = 0.66, p = 0.012) and the Youden index had a sensitivity of 70.0% (56.3-80.9) and a specificity of 62% (42.3-74.5) at a CAP score of > 270. Additionally, BMI was not significantly related to hepatic fat (by MRI), AUC (0.44, 0.69, p-value = 0.323), or to CAP-determined HS, AUC 0.613 (0.425-0.802, p-value = 0.2686). In adolescents with significant obesity, the transient elastography CAP is not an accurate measure of HS compared to MRI. A CAP score of 270 to identify HS is higher than previously described in pediatrics, but may be needed in youth with obesity to improve accuracy. Presentation: Friday, June 16, 2023