Analysis of clinical features of AECOPD at different altitudes and GOLD stages in high-altitude regions

Objective To analyse the clinical features of AECOPD (acute exacerbation of chronic obstructive pulmonary disease) at different altitudes and GOLD (global initiative of chronic obstructive lung disease) stages in high-altitude regions. Method This was a retrospective cross-sectional study. Patients diagnosed with AECOPD through pulmonary function tests and hospitalised in People’s Hospital of the Tibet Autonomous Region from September 2018 to March 2024 were included. Patients were divided into three groups according to their native residential altitude prior to onset: low-altitude group (169 cases, 2700–3700 m), mid-altitude group (77 cases, 3700–4000 m) and high-altitude group (97 cases, 4000–4800 m). Patients were also classified into three groups according to their FEV1%pred in pulmonary function test on admission: mild (91 cases, FEV1%pred ≥80%), moderate (171 cases, 50%≤FEV1%pred