We aimed to collect clinical and radiological data of patients with stable COPD in plateau and plain, and compare the clinical phenotypic characteristics and imaging features of COPD patients in these two areas.

The purpose of this study was to investigate the clinical phenotypic characteristics and imaging features of patients with stable chronic obstructive pulmonary disease (COPD) in plateau and plain. We conducted a cross-sectional study, collecting clinical data of stable patients in plateau and plain, and comparing the clinical phenotypic characteristics and imaging features of COPD patients in these two areas.

Inclusion Criteria:

• meeting the diagnosis of COPD according to Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines and had definite airflow limitation with a post-bronchodilator forced expiratory volume in 1 second (FEV1) / forced vital capacity (FVC)<0.7.

Exclusion Criteria:

• age <40 years;
• subjects with airway diseases other than COPD;
• acute exacerbation of COPD in the past 3 months;
• active tuberculosis;
• cardiovascular or cerebrovascular events in the past 3 months;
• cognitive dysfunction such as vascular dementia or Alzheimer's disease;
• refusal to participate in this study.

We consecutively enrolled patients with COPD from January 2018 to December 2021, who visited the outpatient of Department of Respiratory Medicine in Peking University Third Hospital or Tibet Autonomous Region People's Hospital.