From heart to bad sleep—Lessons for sleep apnoea in times of crisis

Introdução

Obstructive sleep apnoea syndrome (OSAS) is a largely prevalent disorder characterized by repeated episodes of pharyngeal obstruction that causes oxygen desaturation and sleep fragmentation. Besides the consequences of excessive daytime sleepiness including increased risk of traffic and labour accidents, OSAS has been implicated, with great or less evidence, as an independent risk factor for different cardiovascular diseases as hypertension, stroke, heart failure, arrhythmias, coronary heart disease and myocardial infarction.¹ The recognition of OSAS as a treatable putative cause of hypertension and the need for screening is present in international recommendations since 2003.² Several studies have found an association between OSAS and coronary artery disease (CAD). In a large prospective longitudinal study in men and women who were free of CAD at baseline and followed for 8.7 years, after adjustment for multiple risk factors, OSAS was positively associated to myocardial infarction, revascularization procedure or death only in men aged <70 years old (adjusted ratio 1.10 [95% CI 1.00, 1.21] per 10-unit increase in apnoea–hypopnea index), but not in older men or in women of any age.³ Other studies showed that patients suffering from CAD with an AHI greater than 10 events/hour were more prone to die in 5-year follow-up than patients without OSAS (37.5% vs. 9.3%, respectively) after controlling for age, weight, and smoking.^{4, 5} On the other hand in patients with CAD that had percutaneous intervention the probability of restenosis, vessel remodelling and cardiac mortality was greater in the presence of OSAS.^{6, 7} Moreover patients with CAD treated with CPAP...