Table 1_Qi deficiency constitution increases risk of acute mountain sickness via reduced aerobic fitness.docx

BackgroundAcute mountain sickness (AMS) is a common disorder affecting individuals who are exposed to high-altitude environments, generally defined as an elevation of above 2,500 meters. Identifying risk factors for AMS susceptibility before exposure is essential for prevention. According to current research, different constitution types exhibit varying tolerance to acute hypoxia. Exploring the relationship between Traditional Chinese Medicine (TCM) constitution and AMS may therefore provide novel perspectives for prevention and treatment from a TCM standpoint.
MethodsA total of 183 healthy young male participants were enrolled and assessed for TCM constitution, demographic characteristics, clinical indices, and 3,000-meter run performance at low altitude (200 m). After rapid ascent from low altitude to 3,600 m by airplane within 3 h, participants were evaluated for AMS using the Lake Louise Score (LLS). Logistic regression was applied to assess the association between TCM constitution types and AMS, and then linear regression was applied to explore factors associated with Qi deficiency constitution. Structural equation modeling (SEM) was employed to investigate whether aerobic fitness, as reflected by 3,000-meter run performance, mediated the relationship between Qi deficiency constitution and AMS.
ResultsThe incidence of AMS was 40.4%. Among the nine TCM constitution types, only Qi deficiency was independently associated with an increased risk of AMS (adjusted OR = 1.09, 95% CI: 1.01–1.19, p = 0.03). Qi deficiency was significantly associated with 3,000-meter run time, red blood cell count, hemoglobin level, and alcohol intake status. SEM revealed that 3,000-meter run time significantly mediated the association between Qi deficiency and AMS (indirect effect = 0.071, 95% CI: −0.003 to 0.090, p = 0.004), while the direct effect was not statistically significant.
ConclusionQi deficiency constitution is an independent risk factor for AMS, and this association is mediated through reduced aerobic fitness, reflected by 3,000-meter run performance. Assessing TCM constitution could be a new way to identify individuals at higher risk for AMS before high-altitude exposure. Pre-acclimatization strategies aimed at improving Qi deficiency or enhancing aerobic capacity could help prevent AMS in susceptible populations.

背景
急性高原病（Acute Mountain Sickness, AMS）是一种常见疾病，好发于暴露于高海拔环境（通常定义为海拔2500米以上）的人群。在暴露于高海拔环境前明确急性高原病易感性的危险因素，对疾病预防至关重要。现有研究表明，不同体质类型对急性缺氧的耐受程度存在差异。探索中医药（Traditional Chinese Medicine, TCM）体质与急性高原病的关联，或可为从中医药视角开展疾病防治提供全新思路。

方法
本研究共纳入183名健康青年男性受试者，于低海拔（200米）环境下评估其中医药体质、人口学特征、临床指标及3000米跑表现。受试者于3小时内搭乘飞机从低海拔快速升至3600米海拔后，采用路易斯湖评分（Lake Louise Score, LLS）评估其急性高原病发病情况。采用logistic回归分析中医药体质类型与急性高原病的关联，随后通过线性回归探究与气虚体质相关的影响因素。采用结构方程模型（Structural Equation Modeling, SEM）探究以3000米跑表现反映的有氧能力是否在气虚体质与急性高原病的关联中起到中介作用。

结果
本研究中急性高原病的发病率为40.4%。在9种中医药体质类型中，仅气虚体质与急性高原病发病风险升高存在独立关联（校正比值比=1.09，95%置信区间：1.01~1.19，P=0.03）。气虚体质与3000米跑用时、红细胞计数、血红蛋白水平及饮酒状态存在显著关联。结构方程模型分析显示，3000米跑用时在气虚体质与急性高原病的关联中起到显著中介作用（间接效应=0.071，95%置信区间：-0.003~0.090，P=0.004），而直接效应未达到统计学显著性。

结论
气虚体质是急性高原病的独立危险因素，该关联可通过以3000米跑表现反映的有氧能力下降起到中介作用。评估中医药体质可作为一种新方法，用于在高海拔暴露前识别急性高原病高风险人群。旨在改善气虚状态或提升有氧能力的预适应策略，或可帮助易感人群预防急性高原病。