Prediction and Validation of Metabolic Dysfunction-Associated Fatty Liver Disease Using Fatty Liver-Related Indices in a Japanese Population

Background: Recently, metabolic dysfunction-associated fatty liver disease (MAFLD) has been proposed. It is uncertain how indices that predict fatty liver are associated with MAFLD in Japanese. Methods: Among subjects who underwent a health examination at our hospital, 1257 (men: 787, women: 474) subjects participated in fatty liver evaluation of the fatty liver index (FLI) and fatty liver predicting index (FLPI) were included in this cross-sectional study. The discriminatory ability of each index for MAFLD was tested using receiver operating characteristic curve analysis. The association between FLI, FLPI, and MAFLD was investigated using multiple logistic regression analysis. Results: FLI and FLPI had good discriminatory ability for identifying MAFLD in both men and women, with specific cutoff values. Both FLI and FLPI were significantly higher in subjects with MAFLD, and the odds of MAFLD were higher among those in the highest tertile relative to the lowest tertile in both men and women. FLI and FLPI were higher in subjects who met the criteria for both MAFLD and metabolic syndrome (MetS) compared to those who had MAFLD or MetS alone, and most of the examined parameters in subjects with both conditions indicated a high metabolic risk profile. Conclusions: The study suggests that FLI and FLPI are valuable tools for predicting MAFLD and are similarly correlated with the disease. Furthermore, the highest values of these indices were observed in subjects who met the criteria for both MAFLD and MetS, emphasizing the importance of considering both conditions when assessing metabolic risk.