Abstract: The changes of pathophysiology and clinical symptoms in patients with overlap syndrome (OS) are more serious than those of chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea hypopnea syndrome (OSAHS). OS is more prone to cardiovascular disease, which the makes treatment more difficult and prognosis worse. There is a lack of drugs that can significantly slow or prevent the progression of OS and cardiovascular complications. The damage of vascular endothelium is closely related to cardiovascular diseases. At present, COPD and OSAHS have received extensive attention in the vascular endothelial injury and the treatment. This article summarizes the progress in the mechanism of injury of vascular endothelium in OS in recent years, including the damage of hypoxia, inflammation, oxidative stress and changes of sympathetic nerve activity, and summarizes targeted therapy for vascular endothelial injury, mainly including non-invasive ventilator, cell transplantation and targeted drug treatment. This study provides theoretical basis for the clinical treatment and prognosis improvement in patients with OS.

Key words: pulmonary disease, chronic obstructive, sleep apnea, obstructive, endothelium, vascular, review, overlap syndrome