Data_Sheet_1_Education, Altitude, and Humidity Can Interactively Explain Spatial Discrepancy and Predict Short Stature in 213,795 Chinese School Children.pdf

Backgrounds and Objectives: The north–south height distinctions in Chinese children suggest that some geographical–climatic factors could determine height variation of short stature. In a national health survey, we aimed to explore the spatial distribution of short stature on city scales, and detect its socio-economic and geographical–climatic factors.
Methods: Data on the prevalence of short stature were obtained from a 2014 cross-sectional survey of China (CNSSCH). In total, 213,795 Han Chinese students aged 7–18 years, from 106 cities across 30 provinces, were included. Both China and World Health Organization (WHO) growth references were adopted to define short stature.
Results: A spatial clustering was apparent in the distribution of short stature. After multivariable adjustment, altitude and humidity significantly increased the risk of high prevalence in short stature, according to the WHO (odds ratio [OR] = 1.61 and 1.26, 95% confidence interval [CI]: 1.20–2.17 and 1.03–1.54) and China (OR = 1.54 and 1.26; 95% CI: 1.15–2.05 and 1.02–1.55) growth references. Additionally, education significantly decreased the risk of high prevalence in short stature according to the WHO (OR = 0.40; 95% CI: 0.22–0.74) and China (OR = 0.42; 95% CI: 0.22–0.77) growth references. Combining both altitude >400 m and education <9 years, as well as education <9 years and humidity >70%, received the largest effect-size estimate, and significance retained after multivariable adjustment.
Conclusions: Our findings indicate that high altitude and humidity increased the risk of high prevalence in short stature, high education was associated with low prevalence. Additionally, we observed possible interactions between education and altitude/humidity. They may interactively explain spatial discrepancy and predict short stature in Chinese school children. Further validations are necessary.

研究背景与目的：中国儿童身高存在南北分异，提示部分地理-气候因素可能决定身材矮小（short stature）的人群身高变异。本研究基于一项全国健康调查，旨在探索城市尺度下身材矮小的空间分布特征，并识别其社会经济与地理-气候相关影响因素。
研究方法：身材矮小患病率数据来源于2014年中国全国学生健康横断面调查（CNSSCH）。本研究共纳入覆盖全国30个省份106个城市的213795名7~18岁汉族学生。研究采用中国生长参照标准与世界卫生组织（World Health Organization）生长参照标准来定义身材矮小。
研究结果：身材矮小的分布存在明显的空间聚集性。经多变量校正后，无论采用世界卫生组织还是中国生长参照标准，海拔高度与空气湿度均显著升高身材矮小高患病率的风险（比值比（odds ratio, OR）分别为1.61和1.26，95%置信区间（confidence interval, CI）：1.20~2.17、1.03~1.54；中国标准：OR=1.54和1.26，95%CI：1.15~2.05、1.02~1.55）。此外，采用世界卫生组织标准分析显示，受教育水平显著降低身材矮小高患病率的风险（OR=0.40；95%CI：0.22~0.74），中国标准分析结果一致（OR=0.42；95%CI：0.22~0.77）。当同时满足海拔>400m与受教育年限<9年，或受教育年限<9年与空气湿度>70%时，效应量估计值最大，且多变量校正后仍具有统计学显著性。
研究结论：本研究结果表明，高海拔与高空气湿度会升高身材矮小高患病率的风险，较高的受教育水平与低患病率相关。此外，本研究还观察到受教育水平与海拔、湿度之间可能存在交互作用，二者可交互解释中国学龄儿童身材矮小的空间差异并预测其发病风险。后续仍需开展进一步验证研究。