西藏婴幼儿生长迟缓和低体重与海拔的关联——基于倾向性评分匹配分析

目的  西藏自治区(简称西藏)儿童生长发育状况整体不佳，其与中国和WHO的标准相比都有较大差距，本研究基于“西藏0~5岁儿童营养与健康调查”分析西藏婴幼儿生长迟缓和低体重发生率及其与海拔的关系。方法  采用分层、多阶段与规模大小成比例的抽样和整群抽样相结合的抽样方法，抽取0~3岁婴幼儿进行现场体格检查并对其监护人进行问卷调查，采用倾向性评分匹配的方法以均衡两个比较组之间的混杂因素。单因素logistic回归分析模型分析海拔与生长迟缓和低体重的关系。结果  西藏婴幼儿生长迟缓和低体重率分别为20.9%和8.7%。进行1∶1倾向性评分匹配后分别获得324对，共计648例匹配的样本，各混杂因素在比较组间达到均衡。匹配后，相对于居住较低海拔(＜4 000 m)的婴幼儿，居住高海拔(≥4 000 m)的婴幼儿生长迟缓和低体重风险的OR(95% CI)值分别为2.31(1.74~3.10)和1.95(1.27~3.09)。无论男女、家庭收入水平、是否为低出生体重，高海拔都会增加生长迟缓风险，而对低体重的影响只在男性、家庭收入水平较高、出生体重正常和足月生产的婴幼儿中的差异有统计学意义(均有P＜0.05)。结论  西藏婴幼儿生长发育水平低，居住高海拔对生长迟缓有较大影响。

The relationship between stunting and underweight of infants with altitude in Tibet-based on propensity score matching method

  Objective  To investigate the incidence of stunting and underweight of infants in Tibet and its relationship with altitude.  Methods  Multi-stage stratified cluster sampling method was used to select infants aged 0-3 years for on-site physical examination and questionnaire survey of guardians. The propensity score matching method was used to balance the confounding factors between the two comparison groups. Univariate logistic regression was used to analyze the relationship between altitude with stunting and underweight.  Results  The incidence of stunting and underweight of infants in Tibet were 20.9% and 8.7%. After conducting 1∶1 propensity score matching method, 324 pair, 648 matched samples were obtained. The confounding factors were balanced between the comparison groups. After matching, compared with infants living at relative low altitude (< 4 000 meters), the OR and 95% CI of stunting and underweight of infants living at high altitude (≥4 000 meters) were 2.31(1.74-3.10) and 1.95(1.27-3.09), respectively. High altitude increased the risk of stunting regardless of gender, family income level and birth weight. while increased the risk of underweight in boy, infants with high family income level, normal birthweight and term production (all P < 0.05).  Conclusions  The growth and development of infants in Tibet is poor. Living at high altitude has a great impact on growth and development of infants.