Introduction
deaths, COPD
COPD, CHRONIC OBSTRUCTIVE PULMONARY DISEASE, CHRONIC RESPIRATORY DISEASE
Chronic Obstructive Pulmonary Disease (COPD) is the most common chronic respiratory disease and is the third cause of mortality leading to 3.2 million deaths worldwide (Gansu province, located in northwestern China, is characterized by various altitudes (900–3,800 m) and multi-ethnic habitation (In this study, we conducted a cross-sectional study to explore the prevalence of COPD in Gansu and clarify the association between altitude and COPD. Also, a nomogram enrolling candidate risk factors was constructed to screen the high-risk population.