目的 了解兰州市中小学生2014年体重指数(BMI)现况,并初步分析其影响因素。方法 以随机整群抽样的调查方法选取兰州市7～18岁汉族中小学生共4 200人作为样本,测量其身高、体重等指标并计算BMI;调查问卷采用《2014年全国小学生体质健康状况调查研究实施方案》中的附录问卷;BMI单因素分析采用 χ²检验,采用多因素 Logistic回归分析BMI影响因素。结果 在4 200名调查对象中,消瘦占13.02%,正常占73.52%,超重占9.36%,肥胖占4.10%;BMI的分布在各年龄组不同性别、城乡之间差异均有统计学意义;多因素Logistic回归分析发现,中小学生肥胖、超重的发生与城乡、性别、睡眠时间以及吃早餐的频次有关(OR=1.67,2.07,1.52,1.39,P均<0.05);消瘦的发生与城乡、性别、睡眠时间、喝牛奶的频率以及平均每天看电视的时间有关(OR=0.71,1.31,1.56,1.40,0.81,P均<0.05)。 结论 兰州市7～18岁中小学生的BMI的肥胖率在性别、城乡之间的分布存在差异。今后的学校卫生工作中应加强针对中小学生的健康教育,培养他们健康合理的饮食和生活习惯,促进儿童青少年的健康成长。

Objective To investigate the distribution and the influencing factors of body mass indes(BMI) in primary and middle school students in Lanzhou in 2014. Methods A total of 4 200 students aged 7～18 in Lanzhou were selected by stratified random sampling. The height,weight of students were measured to calculate BMI. The questionnaires were from the detailed measurement rules about Investigation of the Chinese Students′ Physical Fitness in Year 2010. χ² test and multivariate-Logistic regression analysis were used to analyze influencing factors. Results Totally 13.02%,73.52%,9.36% and 4.10% of the 4 200 students were with underweight,normal weight,overweight and obesity respectively. There were significant differences on BMI in children with different genders and dwelling place(P＜0.05). Multivariate-Logistic regression analysis showed students′ obesity and overweight were related to district,sex,sleeping-time,frequency of breakfast (OR=1.67,2.07,1.52,1.39,all P<0.05).And underweight in students was associated with district,sex,sleeping-time,frequency of having milk,watching TV(OR=0.71,1.31,1.56,1.40,0.81,all P<0.05). Conclusions The distribution of BMI and obesity status vary with gender,district and ages. Also,the health of primary and middle school students can be improved by strengthening health education and developing healthy diet and living habits.