Objective: To identify controlled attenuation parameter (CAP) based cutoffs for diagnosing and grading hepatic steatosis in adolescents with overweight/obesity, using magnetic resonance imaging-proton density fat fraction (MRI-PDFF) as the reference method.
Methods: Adolescents with overweight/obesity were included. Fasting glucose, insulin, aspartate aminotransferase, and alanine aminotransferase were estimated. Hepatic steatosis (S) was assessed by MRI-PDFF, and graded as S0, S1, S2, and S3 with fat fraction cutoffs of < 6.0%, ≥ 6.0% to < 17.5%, ≥ 17.5% to < 23.3%, and ≥ 23.3%, respectively. CAP and liver stiffness measure (LSM) were assessed using FibroScan. Receiver operating characteristic (ROC) curves were used to estimate the CAP scores predicting various grades of hepatic steatosis.
Results: A total of 108 adolescents aged 12.4 ± 1.9 y, with mean BMI of 26.7 ± 4.9 kg/m2 were included. S0, S1, S2, and S3 steatosis by MRI-PDFF was identified in 15, 70, 13, and 10 adolescents, respectively. A moderate positive correlation was observed between CAP score and MRI-estimated hepatic fat (r = 0.528, p < 0.001). The optimal CAP cutoffs for identifying ≥ S1, ≥ S2, and S3 steatosis were 271 [area under ROC (AUROC) 0.745 (0.630-0.859)], 296 [AUROC 0.820 (0.728-0.911)], and 309 dB/m [AUROC 0.836 (0.729-0.944)], respectively.
Conclusion: CAP score had a good discriminative ability to diagnose fatty liver in adolescents with overweight or obesity.
Keywords: Adolescent obesity; Elastography; Hepatic steatosis; LSM; NAFLD; Pediatric obesity.
© 2021. Dr. K C Chaudhuri Foundation.