A longitudinal study on sex difference in weight growth and systolic blood pressure change among children and adolescents in Beijing

Abstract

Objective To explore sex differences between weight and systolic blood pressure (SBP) changes among school-age children and adolescents in Beijing, and to provide a basis for priority intervention to control the rapid growth of body weight and blood pressure.

Methods Anthropometric, measurement data of 70 288 children and adolescents from primary and high schools in Shunyi District were collected from 2009 to 2018, and a longitudinal dataset with complete data related to weight and BP after individual data linkage was compiled. The age-specific weight and SBP growth rates were calculated, and a linear mixed-effects model was used to identify sex differences in chronological growth rates.

Results Weight and SBP increased with age in both boys and girls, and the mean weight and SBP were higher in boys than in girls across all age groups. The result of the linear mixed-effects model indicated apparent sex differences in weight and SBP growth rates, with an age and sex interaction term ( β=−0.35, −0.40, P<0.01). The age at peak weight velocity (PWA) was 12 years old and the age at peak SBP velocity was 13 years old in boys, which occurred one and three years later than for girls, respectively. In addition, the peak weight and SBP velocity were higher in boys than in girls. The curves of the SBP growth rate adjusted for the PWA, showed that the peak SBP velocity occurred two years before PWA and the second peak SBP velocity occurred at the PWA, which indicated “double peaks” in both boys and girls. The SBP growth rate was always higher in boys than in girls, and the rates declined after PWA.

Conclusion Sex differences in weight and SBP growth rates were persistent and obvious in school-age children and adolescents in Beijing and the change in SBP was highly time synchronized with the increase in weight.

Abstract

【摘要】 目的 探索北京市学龄儿童青少年体重增长与收缩压变化的性别差异, 为控制体重和血压的快速增长提供依 据。 方法 基于北京市顺义区 2009—2018 年中小学生体检资料, 经匹配个人信息后形成 70 288 人具有完整体重、收缩压 的纵向数据库, 计算年龄别体重、收缩压及其增长速度, 与以体重增速高峰年龄 (PWA) 为基点的收缩压增长速度, 采用混 合效应线性模型分析增速的性别差异。 结果 男、女生体重、收缩压均随年龄增长而升高, 各年龄段男生体重、收缩压均高 于女生。混合效应线性模型结果显示, 体重和收缩压增长速度存在性别年龄交互作用 ( β 值分别为−0.35, −0.40, P 值均<0.01), 即各年龄段体重、收缩压增长速度具有性别差异。年龄别增长速度曲线显示, 男生分别于 12 和 13 岁达到体重增速 高峰和收缩压增速高峰, 比女生晚 1 年和 3 年, 但增长速度高峰均高于女生。收缩压调整 PWA 后的增长速度曲线显示, PWA 出现前 2 年, 男、女生发生增速高峰, 在 PWA 出现次高峰, 在 PWA 后显著下降且男生收缩压增长速度始终高于女生。 结论 北京学龄儿童青少年体重与收缩压增长速度和规律存在性别差异, 并且收缩压变化与体重增加密切相关。