Retrospective Study of Serum Vitamin D Levels and Metabolic-Associated Fatty Liver Disease in 222 Children and Adolescents Aged 6-18 Years With Obesity

BACKGROUND Vitamin D deficiency is common in pediatric obesity and has been proposed to contribute to metabolic-associated fatty liver disease (MAFLD). This retrospective study aimed to evaluate serum 25-hydroxyvitamin D (25[OH]D) levels and MAFLD in 222 children and adolescents aged 6-18 years with obesity. MATERIAL AND METHODS Records of 222 patients with obesity (body mass index ≥95th percentile) were reviewed. Hepatic steatosis was assessed by abdominal ultrasonography; MAFLD was defined as hepatic steatosis in the presence of obesity. Anthropometric measures and routine metabolic laboratory results were extracted. Serum 25(OH)D was analyzed when available and categorized as deficient (20 ng/mL). Groups with and without MAFLD were compared, and 25(OH)D was evaluated across steatosis grades. RESULTS MAFLD was identified in 135 of 222 patients (60.8%). Male sex was associated with higher likelihood of MAFLD (OR, 2.75; 95% CI, 1.46-5.16). The MAFLD group exhibited a less favorable metabolic profile, including higher HOMA-IR, HbA1c, ALT, and AST, and lower HDL-C (all P≤0.05) than non-MAFLD obesity group. Serum 25(OH)D was available in 148 participants and showed no difference between the MAFLD and non-MAFLD obesity groups (P=0.782); similarly, 25(OH)D levels were not associated with ultrasonographic steatosis grade (P=0.686). CONCLUSIONS MAFLD was common in pediatric patients with obesity and was associated with an adverse metabolic profile; however, serum 25(OH)D was not associated with MAFLD or steatosis grade. Clinical care should prioritize metabolic risk assessment, and prospective studies are required to clarify vitamin D's role in pediatric MAFLD.