Clinical characteristic and prognosis of adult inpatients with high altitude pulmonary edema: a multi-central, retrospective study in plateau of China from 2012 to 2022.

BACKGROUND: High-altitude pulmonary edema (HAPE) is a common consequence of inadequate acclimatization to high altitude. However, there is currently limited evidence regarding the clinical characteristics and risk factors contributing to adverse outcomes in patients with HAPE. METHODS: This study enrolled 411 patients with HAPE from four hospitals in the plateau, between 2012 and 2022, and described their clinical characteristics. The relationship between the altitude of onset and the duration of stay in plateau and adverse outcomes was analyzed using restricted cubic splines. Stepwise logistic regression was conducted to investigate the risk factors for adverse outcomes in HAPE patients. RESULTS: The risk of pulmonary hypertension in HAPE patients was positively associated with onset altitude, while the risk of pulmonary hypertension, thrombosis, high-altitude cerebral edema, and death was negatively related to duration of stay in plateau (P for overall association =0.029, P for nonlinear association =0.071). The multivariate logistic model showed that HAPE patients with onset altitude of ≥ 3,500 m, duration of stay in plateau ≤ 1-day, elevated lactic dehydrogenase and prolonged prothrombin time had a higher risk of pulmonary hypertension (OR = 0.42, 95% CI: 0.23–0.74). Patients with a history of hypertension and longer hospital stays had an increased risk of thromboembolism (OR = 6.71, 95% CI: 1.77–25.46). Fever (OR = 3.16, 95% CI: 1.17–8.55), headache (OR = 2.79, 95% CI: 1.37–5.65), and elevated blood urea nitrogen (BUN) levels (OR = 3.94, 95% CI: 1.93–8.04) were risk factors for high-altitude cerebral edema. Additionally, mortality risk was higher in patients with headache (OR = 2.11, 95% CI: 1.01–4.39), pulmonary hypertension (OR = 2.96, 95% CI: 1.08–8.13), high-altitude cerebral edema, and elevated BUN (OR = 5.26, 95% CI: 2.39–11.59) and N-terminal pro-brain natriuretic peptide levels (OR = 2.63, 95% CI: 1.20–5.78). CONCLUSIONS: Our findings indicate the importance of careful assessment and management of clinical indicators and risk factors in patients with HAPE, further to take effective early interventions.