Comparison Of noninvasiv Indexes in the Determination of NAFLD in Obese Adolescents And A Recommendation For A Diagnostic Chart

Introduction: Non-alcoholic fatty liver disease (NAFLD) is an increasingly common health issue in obese children and adolescents. NAFLD does not occur in every obese patient and in some cases, ultrasonography is inadequate for diagnosis.In this study, BMI SDS, WC SDS, triponderal mass index (TPMI), HbA1c, HOMA-IR, TG/HDL, LAP index, triglyceride-glucose (TyG) index and aminotransferase index, used in the diagnosis of NAFLD in obese adolescents,were examined together and their diagnostic values for clinical use were compared. Material and method: Adolescents who presented at a pediatric clinic between January and August 2022 and who had been diagnosed with exogenous obesity without any comorbidities,were included in the study.The presence of NAFLD was assessed using liver MRI. Laboratory findings were obtained retrospectively from the system records. Gender, HOMA-IR, TyG index and aminotransferase index were evaluated using logistic regression analysis. Results: In the comparison between NAFLD(+) and NAFLD(-) obese adolescent groups, HbA1c, HOMA-IR, aminotransferase index and TyG index were higher in the NAFLD (+) group (p = 0.012;p = 0.001; p = 0.012; p = 0.002, respectively). There was a positive correlation between liver fat percentage and HOMA-IR,TyG index,aminotransferase index and TG/HDL. According to regression analysis, male gender and HOMA-IR elevation were determined to be significant risk factors for NAFLD). Conclusion: Even if no NAFLD is detected on USG imaging, evaluation of HOMA-IR and TyG index levels, especially in high-risk patients, will support the diagnosis of NAFLD. In obese adolescents with a HOMA-IR value of ≥ 4.55and a TyG index value of ≥ 8.38, evaluation should be made with liver MRI, even if no NAFLD is detected on USG imaging. A basic chart with ALT, HOMA-IR, TyG, and gender with a diagnostic accuracy of 80%, positive predictive value of82.5% and sensitivity of 80% may assist in diagnosis of NAFLD in obese adolescents.