With the improvement of economic level and changes in lifestyle of residents, the obesity among children and adolescents has become increasingly severe, threatening the healthy growth of children and adolescents. BMI was used as an evaluation index of obesity in most previous studies, which may underestimate the prevalence of central obesity. Therefore, it is urgent to evaluate the waist circumference (WC) and trend of the prevalence of central obesity among children and adolescents in Putuo District, in order to provide scientific basis for targeted proposed intervention.

To analyze WC and the trend in the prevalence of central obesity among children and adolescents aged 7-18 years in Putuo District, Shanghai, from 2018 to 2023.

Data on medical examinations of primary and secondary school students in Putuo District in 2018 and 2020 to 2023 were used to analyze the WC, the prevalence of central obesity and the trends. The 90th percentile (P₉₀) age-specific children and adolescents of different genders was used as the cut-off point of high WC, and WC exceeding the P₉₀ value was defined as central obesity. SPSS 22.0 and SAS 13.1 were used for statistical analysis and Excel 2021 was used for graphic plotting.

A total of 280 648 primary and secondary school students participated in the medical examination in Putuo District, Shanghai, from 2018 to 2023, of which 146 334 (52.1%) were male students and 134 314 (47.9%) were female students, with an median age of 10.5 (8.7, 12.6) years. WC of male and female students from 2018 to 2023 showed fluctuating downward trends with a statistically significant difference (H_male=209.785, H_female=373.076; P<0.001). WC of male students decreased from 65.2 (58.0, 74.0) cm in 2018 to 64.8 (56.9, 74.0) cm in 2023 and female students decreased from 60.5 (55.0, 67.0) cm to 59.8 (53.8, 66.2) cm. Comparison of the prevalence of central obesity among male and female students in each year showed statistically significant differences (χ²_male=264.123, χ²_female=448.289; P<0.001). The results of Cochran-Armitage trend test showed decreasing trends in prevalences of central obesity among male and female groups from 2018 to 2023 (Z_{trend male}=-10.974, Z_{trend female}=-15.218; P_trend<0.001). The prevalence of central obesity among male students decreased from 28.8% (6 714/23 286) to 24.6% (7 935/32 227), while that among female students decreased from 21.9% (4 604/21 062) to 15.5% (4 604/29 695). The WC and prevalence of central obesity among male students were higher than that among female students (U=7 128 257 114.500、χ²=2 928.075, P<0.001). Prevalence of central obesity showed increasing trends with age for both sexes (Z_{trend male}=35.167, Z_{trend female}=6.533; P_trend<0.001) .

This study suggests that WC and the prevalence of central obesity among children and adolescents aged 7-18 in Putuo District are fluctuating and decreasing. WC and the prevalence of central obesity of male students are high than those of female students of the same age. The prevalence of central obesity is increasing with age. Results of this study provide theoretical support for the targeted intervention of central obesity in children and adolescents.

随着居民经济水平的提高及生活方式的改变，儿童青少年肥胖问题日益严峻，威胁着儿童青少年的健康成长，目前多数研究主要以BMI作为儿童青少年肥胖的评价指标，可能低估了儿童青少年中心性肥胖水平。因此，亟需评价儿童青少年中心性肥胖水平及变化趋势，为有针对性提出干预措施提供科学依据。

分析2018—2023年上海市普陀区7~18岁儿童青少年腰围水平及中心性肥胖率变化趋势。

利用2018年、2020—2023年上海市普陀区中小学生健康体检数据，分析普陀区7~18岁儿童青少年腰围水平、中心性肥胖率及变化趋势。以不同性别儿童青少年年龄别第90百分位数（P₉₀）作为儿童青少年高腰围界值点，将腰围超过同年龄同性别组的P₉₀值定义为中心性肥胖。应用SPSS 22.0、SAS 13.1软件进行统计学分析、Excel 2021进行图形绘制。

2018—2023年参加上海市普陀区中小学生健康体检学生共280 648人次，其中男生146 334人次（52.1%），女生134 314人次（47.9%），中位年龄为10.5（8.7，12.6）岁。2018—2023年男女生腰围整体水平呈波动下降趋势，差异有统计学意义（H_男=209.785、H_女=373.076，P<0.001），男生由2018年的65.2（58.0，74.0）cm下降至2023年的64.8（56.9，74.0）cm，女生由60.5（55.0，67.0）cm下降至59.8（53.8，66.2）cm。2018—2023年男女生组各年份中心性肥胖率比较，差异均有统计学意义（χ²_男=264.123、χ²_女=448.289，P<0.001）；Cochran-Armitage趋势检验结果显示，2018—2023年男女生组中心性肥胖率整体呈下降趋势（Z_趋势男=-10.974，Z_趋势女=-15.218，P_趋势<0.001）；男生中心性肥胖率由2018年的28.8%（6 714/23 286）下降至2023年的24.6%（7 935/32 227），女生中心性肥胖率由21.9%（4 604/21 062）下降至15.5%（4 604/29 695）。男生整体腰围水平及中心性肥胖率均高于女生（U=7 128 257 114.500、χ²=2 928.075，P<0.001）。男女生中心性肥胖率随年龄增长呈上升趋势（Z_趋势男=35.167，Z_趋势女=6.533，P_趋势<0.001）。

本研究提示普陀区7~18岁儿童青少年腰围水平、中心性肥胖率呈波动下降趋势；男生腰围水平和中心性肥胖率较同年龄女生高；中心性肥胖率随年龄增长呈上升趋势，本研究结果为后续有针对性开展儿童青少年中心性肥胖干预工作提供了理论支持。