Abstract: Objective To investigate the changes of serum 25-hydroxyvitamin D[25(OH)D] levels and its clinical significance in obese children with nonalcoholic fatty liver disease (NAFLD). Methods The clinical data of 120 obese children admitted to our hospital from April 2021 to April 2023 were selected for a correlation analysis. According to whether the children had NAFLD or not, they were divided into an obesity group with NAFLD and an obesity group without NAFLD, with 54 cases and 66 cases in each group, respectively. The clinical data of the two groups were compared. Multivariate logistic regression was used to analyze the risk factors of NAFLD in obese children. Results There were 34 (62.96%) boys in the obese NAFLD group and 28 (42.42%) boys in the obese group (χ²=5.017, P=0.025). The average age of the obese MAFLD group was (12.23±3.04) years, and that of the obese group was (10.48±2.62) years (t=3.386, P=0.001). Body mass index (BMI) in the obese NAFLD group was (30.07±5.11) kg/m², and that of the obese group was (25.06±2.55) kg/m² (t=6.978, P=0.000). Triglyceride (TG) in the obese NAFLD group was (1.29±0.32) mmol/L, and that of the obese group was (0.88±0.24) mmol/L (t=8.015, P=0.000). Low-density lipoprotein cholesterol (LDL-C) in the obese NAFLD group was (2.54±0.74) mmol/L, and that of the obese group was (2.29±0.52) mmol/L, (t=2.168, P=0.032). Fasting insulin (FINS) in the obese group was (12.68±3.84) mmol/L and that of the obese group was (9.67±3.11) mmol/L (t=4.745, P=0.000). Homeostasis model assessment-insulin resistance (HOMA-IR) of the obese NAFLD group was (2.05±0.34) and that of the obese group was (1.78±0.38) (t=4.058, P=0.000). Alanine transaminase (ALT) in the obese NAFLD group was (52.74±14.81) U/L and that of the obese group was (24.16±7.22) U/L (t=13.808, P=0.000). Aspartate transaminase (AST) in the obese NAFLD group was (36.02±10.14) U/L and that in he obese group was (22.44±6.43) U/L (t=8.912, P=0.000). Serum 25-hydroxyvitamin D [25(OH)D] in the obese NAFLD group was (21.03±5.14) ng/mL, and that of the obesity group was (25.08±6.86) ng/mL (t=3.590, P=0.001). Logistic analysis showed that BMI and HOMA-IR were independent risk factors, and 25(OH)D was a protective factor for NAFLD in obese children (P<0.05). Conclusion Serum 25(OH)D level in obese children with NAFLD are significantly decreased. The. monitoring of serum 25(OH)D level may provide guidance for formulating clinical protocols.

Key words: Obese children, Nonalcoholic fatty liver disease, 25-hydroxyvitamin D