Abstract
BACKGROUND: Acute mountain sickness (AMS) presents a significant health risk for individuals rapidly ascending to high altitudes, with its occurrence influenced by both environmental and individual factors. The Traditional Chinese Medical Constitution (TCMC), a holistic framework describing an individual's health disposition and disease susceptibility shaped by both innate and acquired factors, may be linked to AMS susceptibility. However, evidence supporting this connection is scarce. OBJECTIVE: This study aims to explore the TCMC types most susceptible to AMS and identify key influencing factors in populations rapidly ascending to Tibet. METHODS: A cross-sectional study was conducted with 1,482 eligible healthy male participants aged 18-40 years. Data were collected at two time points-before and after exposure to a high-altitude environment-covering three categories: (1) Baseline physiological measurements, including blood pressure, heart rate, peripheral oxygen saturation (SpO(2)), and body temperature; (2) Anthropometric indicators such as height, weight, and body mass index (BMI); (3) Questionnaire and scale assessments, including demographic information, the Self-Rating Anxiety Scale (SAS), Pittsburgh Sleep Quality Index (PSQI), and TCMC classification assessment scale. AMS was diagnosed using the Lake Louise Score (LLS) exclusively in the high-altitude environment. Spearman correlation analysis and Multivariable logistic regression (backward stepwise method) were used to identify AMS-related and independent risk factors. RESULTS: The overall AMS incidence was 32.9% (488/1482). The prevalence of unbalanced constitutions was significantly higher in the AMS group compared to the non-AMS group (32.6% vs. 7.6%; P < 0.001). Among AMS patients with unbalanced constitutions, Qi-deficiency was the most prevalent (78.0%). The highest AMS incidence (72.9%) was observed in individuals with a Qi-deficiency constitution. Multivariable analysis identified anxiety (OR = 1.16, 95% CI: 1.08-1.25, P < 0.001), insomnia (OR = 1.09, 95% CI: 1.03-1.16, P = 0.003), unbalanced constitution tendency (OR = 1.06, 95% CI: 1.02-1.10, P = 0.002), and lower SpO(2) (OR = 0.91, 95% CI: 0.87-0.95, P < 0.001) as independent risk factors. BMI showed a weak positive association (OR = 1.02, 95% CI: 1.00-1.04; P = 0.041). CONCLUSION: Qi-deficiency is the most common TCMC type associated with AMS susceptibility. Key modifiable risk factors include insomnia, anxiety, and low SpO(2). These findings suggest the importance of implementing TCMC-differentiated prevention strategies for AMS, including preemptive interventions to tonify Qi for susceptible individuals, psychological support, and sleep optimization.