Metabolic features in plasma and urine of obese children and their association with MAFLD risk

Objective: This study aimed to identify metabolic features in obese children that are associated with metabolic dysfunction-associated fatty liver disease (MAFLD), to explore the dose-response relationship between these metabolites and MAFLD, and to identify any differences depending on sex of the child. Methods: Obese children recruited from the outpatient clinic were categorized into obese with MAFLD (OB-MAFLD) and obese without MAFLD (OB-CON) groups via B-ultrasound. Anthropometric and laboratory examinations were conducted. Metabolomic analysis was performed using liquid chromatography-tandem mass spectrometry. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were employed to identify differential metabolites. Logistic regression models were utilized to evaluate the associations between these metabolites and MAFLD risk, with gender-stratified analyses performed. Restricted cubic spline (RCS) regressions were applied to explore the dose-response relationship between these metabolites and MAFLD. Results: > 0.05 for-nonlinearity). Conclusion: Plasma and urinary metabolite alterations in obese children may confer either susceptibility to or protection against MAFLD development, with distinct sex-specific patterns. These metabolites may serve as quantitative biomarkers and therapeutic targets, advancing precision intervention strategies for obesity-associated MAFLD.