Obstructive Sleep Apnea Is Associated With Severity And Long-term Prognosis Of Acute Coronary Syndrome

Background: Obstructive sleep apnea(OSA)is a common disease caused by the collapse of the upper airway during sleep,which leads to transient asphyxia that affects 26–69% of the acute coronary syndrome(ACS)population.Some study revealed OSA is associated with an increased risk of fatal and nonfatal cardiovascular events.Nevertheless,a cardio-protective role of OSA in ACS patients,via ischemic preconditioning,has also been postulated.The goal of this study was to evaluate the influence of obstructive sleep apnea on the severity and prognosis of patients admitted for acute coronary syndrome.Methods: Prospective cohort study.We enrolled patients with ACS who undergone polysomnography and coronary angiogram or percutaneous coronary intervention.Patients with an apnea–hypopnea index(AHI)>15 events·h-1 were considered as moderate to severe OSA group(n=373).Those with an AHI?15 events·h-1 were considered controls(n=156).After follow up,we compared the acute coronary syndrome severity(ejection fraction,number of diseased vessels,SYNTAX score,length of hospitalization and plasma troponin I et al.)and long-term major adverse cardiovascular events(MACE,the composite of cardiac death,myocardial infarction,unplanned revascularization,or heart failure requiring hospitalization)according to the category of OSA.Results: We finally collected 529 patients' data(AHI 29±19 h-1,59±10 years,76% males,follow-up duration 28 ±4.6 months).Patients with moderate or severe OSA exhibited a higher prevalence of systemic hypertension(75.3% versus 64.1%,P=0.009).as well as higher body mass index(28.1±3.6 kg·m-2 versus 26.4±3.4 kg·m-2,p<0.001),SYNTAX score(10.1±5.4 versus 3.0±6.4,p<0.0001),Epworth score(6.2±5.4 versus 4.5±3.9,p<0.0001)and length of hospitalization(8.0±5.6 versus 6.7±4.2,p=0.007)compared with controls.The event rate at 30 months was higher in the moderate to severe OSA than the control group(8.6% versus 3.2%,p = 0.028).After adjusting for baseline confounders by Cox regression model,AHI was an independent risk factor of long-term MACE(HR = 2.758,95% CI 1.068-7.122).Conclusions: The results of this study demonstrate that moderate or severe OSA is correlated with disease severity and associated with worse long-term prognosis in ACS patients.