Relationship between obesity related indicators and non-alcoholic fatty liver disease in children: a systematic review and meta-analysis

BACKGROUND: The incidence of childhood obesity is increasing. There is some controversy about the association between overweight and nonalcoholic fatty liver disease (NAFLD) in children. This article intends to compare the differences in these obesity related parameters between NAFLD children and healthy control children through meta-analysis to provide evidence-based medical evidence for clinical use. METHODS: The literature were extracted from English and Chinese databases. Statistical analysis was performed using Stata/SE 16.0, IBM SPSS Statistics 26, and Review Manager 5.4 software. RESULTS: A total of 15 original case control studies were included, including 12 high-quality literature, 3 medium quality literature. The total sample size included in the analysis was 1,595 children, including 824 in the experimental group and 771 in the control group. The results of meta-analysis showed that the body mass index (BMI) of the NAFLD group was significantly higher than that of the control group [mean difference (MD) =1.05, 95% confidence interval (CI): 0.36–1.73]. Waist circumference of the NAFLD group was significantly larger than that of the control group (MD =1.66, 95% CI: 0.60–2.73). Triglyceride level in the NAFLD group was significantly higher than that in the control group (MD =1.08, 95% CI: 0.05–2.12). Low-density lipoprotein (LDL) level in the NAFLD group was significantly higher than that in the control group (MD =0.49, 95% CI: 0.12–0.85). In addition, fasting blood glucose of the NAFLD group was significantly higher than that of the control group (MD =0.31, 95% CI: 0.09–0.54) and insulin resistance index of the NAFLD group was significantly higher than that of the control group (MD =2.95, 95% CI: 1.41–4.49). Exercise had a significant effect on improving the degree of NAFLD in children [odds ratio (OR) =2.51, 95% CI: 1.83–3.43]. CONCLUSIONS: Various physical indicators were related to obesity, including BMI, waist circumference, triglyceride content, LDL, fasting blood glucose, and insulin resistance index, and all were significantly correlated with NAFLD in children, provided a reference for future clinical diagnosis and treatment work. In addition, exercise could significantly improve the degree of steatosis in children with NAFLD.