Evaluation of Association Between Obstructive Sleep Apnea and the Severity of Coronary Artery Disease

Before initiating the study, all potential subjects were invited to attend an educational program that explained the purpose and methodology of this study. After getting informed consent from patients, demographic data including age, sex, medical history (including comorbidities and risk factors), current medicine, lifestyle habits, height (cm), and weight (kg) were recorded, and body mass index (BMI) was calculated as weight divided by height squared (kilograms per square meter, kg/m2). The included subjects need to perform transthoracic echocardiography or provide an echocardiographic examination within one month. CAD diagnosis was determined based on the results of the coronary angiography, using stenosis 50% cutoffs considered have coronary diseases or not.

Consecutive patients of both sexes with coronary angiography from outpatient or inpatient departments of Fuwai Hospital were recruited into the study. The inclusion criteria were Chinese, aged 35 to 75 years with CAD verified by coronary angiography, and able to give informed written consent. The subjects were excluded if they had New York Heart Association Class III-IV degree with ejection fraction < 45%, severe pulmonary disease, significant psychiatric disease, or history of pharyngeal surgery for OSA or current use of CPAP treatment for OSA. They were also excluded if they declined to participate or were unable to provide informed consent.