上海地区1180名在校儿童非酒精性脂肪性肝病检出率及危险因素分析

The prevalence of non-alcoholic fatty liver disease and its related risk factors in 1180 school children in Shanghai

目的探讨上海地区儿童NAFLD检出率及相关危险因素。方法调查上海市浦东新区6～14岁学生共1180名,所有学生均测量身高、体重、腰围、臀围、血压并计算体重指数（BMI）和腰臀比,每名学生均进行肝脏B超检查。结果1180名学生中,男生572名,年龄（9.0±2.0）岁,女生608名,年龄（9.1±1.8）岁。1155名（97.9%）学生肝脏B超正常,25例为NAFLD患者,其中轻度18例（1.5%）,中度7例（0.6%）,没有重度患者。25例NAFLD患者中,男生19例,女生6例,男生NAFLD检出率远高于女生,差异有统计学意义（x^2=6.66,P〈0.05）。1180名学生中934名（79.2%）BMI正常,超重和肥胖学生分别为137名（11.6%）和109名（9.2%）。NAFLD检出率在BMI正常学生中仅为0.6%（6/934）,而超重和肥胖学生中则分别为2.9%（4/137）和13.8% （15/109）,超重和肥胖学生NAFLD检出率高于BMI正常的学生,差异有统计学意义（x^2=85.93,P〈0.01）。依据儿童生长发育的特点将1180名学生分为发育前期（6～9岁）和发育期（〉9～14岁）两组,则6～9岁组学生NAFLD检出率为1.7%（12/714）,〉9～14岁组学生NAFLD检出率为2.8% （13/466）,两组比较差异无统计学意义（x^2=2.01,P〉0.05）。以NAFLD发生为最终目的,进行Logistic回归分析,BMI和腰臀比是NAFLD发生的有效预测指标（x^2=69.35,P〈0.01）。结论上海地区1180名儿童NAFLD检出率为2.1%。超重和肥胖学生NAFLD检出率明显高于BMI正常学生,男生检出率高于女生。BMI和腰臀比可作为NAFLD发生的有效预测指标。

Objective To evaluate the prevalence of non-alcoholic fatty liver disease （NAFLD） and its related risk factors in children in Shanghai. Methods A total of 1180 students aged 6 to 14 years （9.0 ± 1.9） y from two elementary schools in the Pudong New Area were enrolled in our study, 572 were male and 608 were female. Height, body weight, waist circumference, hip circumference, waist-hip ratio （WHR）, blood pressure were measured and liver ultrasound B scans were analyzed for each student. Body mass index （BMI） was calculated as body weight in kilograms divided by the square of height in meters. Results Liver ultrasonic images were normal in 1155 students （97.9%）, 18 students had mild fatty livers （1.5%） and 7 （0.6%） students had moderate fatty livers, while none of the students had severe fatty livers. Of all the NAFLD students, 19 were male and 6 were female. The prevalence of NAFLD in male students was obviously higher compared with that in female students （ x^2= 6.66, P 〈0.05）. The number of students with normal BMI was 934 （79.2%）, while 137 （11.6%） and 109 （9.2%） respectively were overweight and obese, according to the age and gender specific BMI chart for Chinese children. The prevalence of NAFLD in students with normal BMI was 0.6% （6/934）, while it was 2.9% （4/137） and 13.8% （15/109） in overweight and obese students. The prevalence of NAFLD in overweight and obese students was higher than that in students with normal BMI （ x^2 = 85.93, P 〈 0.01）. All the students were further divided into two groups based on age： group 1,714 prepubertal students age 6 to 9 years; group 2, 466 students in puberty stage age 10 to 14 years. The prevalence of NAFLD was 1.7% （12/714） in group 1 and 2.8% （13/466） in group 2. There was no statistical difference between the two groups （ x^2 = 2.01, P 〉 0.05）. A stepwise multiple regression analysis was performed to evaluate the relationship between NAFLD and its related factors. BMI and WHR were chosen as predictors of NAFLD （ x^2 = 69.35, P 〈 0.01）. Conclusion Based on liver ultrasound, the prevalence of NAFLD is 2.1% of the 1180 surveyed school students age 6 to 14 years, The prevalence of NAFLD was obvious higher in overweight and obese students compared with that in students with normal BMI. Male students had more NAFLD than female students. BMI and WHR could be used as effective indexes to predict the occurrence of NAFLD.