Association of Adolescent Obesity with Nonalcoholic Fatty Liver Disease and Related Risk Factors in Xi 'an, China

Introduction and aim. To investigate the association of adolescent obesity with nonalcoholic fatty liver disease (NAFLD) and related risk factors in Xi 'an, China. Material and methods. A total of 4141 adolescents (2,061 girls and 2,080 boys, mean age: 18.62 +/- 0.66 years, age range 15-22 years) were enrolled in this investigation. Anthropometric index was measured, and liver ultrasonography and liver function biochemical test were performed in all the subjects. T test, chi(2) test and logistic regression analysis were used for statistical analyses. Results. The total rates of obesity was 7.9% (08/4,141). The prevalence rate of NAFLD was 8.1% (335/4141) with a declining trend from obesity, overweight to normal BMI. NAFLD prevalence rate in obese boys was significantly higher than in girls (chi(2) = 56.5, P < 0.01). BMI, body weight, ALT, and AST in NAFLD group were higher than in non-NAFLD group (P < 0.05). The tangent point of ALT was 36 U/L using Youden index in boys, and 33 U/L in girls. Conclusion. The prevalence of obesity and NAFLD in adolescents is higher in Xi'an than anticipated. Body weight and BMI may be the associated independent risk factors of NAFLD.