Effect Of Obstructive Sleep Apnoea On Cardiovascular Outcomes In Patients With Acute Coronary Syndrome: A Secondary Analysis Of The Riccadsa Trial

Background There is a controversy after the results of the ISAACC trial regarding the prognostic significance of obstructive sleep apnoea (OSA) in patients with acute coronary syndrome (ACS). Aims and Objective: We addressed if patients with ACS with OSA have increased risk for major adverse cardiovascular and cerebrovascular events (MACCE) compared to ACS patients without OSA. Methods: The current study was a secondary analysis of the ACS subgroup (n=255) of the RICCADSA trial, conducted in Sweden between 2005 and 2013. The OSA group (n=174) consisted of revascularized patients with: a) nonsleepy OSA (apnoea-hypopnoea index [AHI] ≥15/hr, and Epworth Sleepiness Scale [ESS]<10), who were randomized to no continuous positive airway pressure (CPAP) therapy (n=78), b) nonsleepy or sleepy (ESS≥10) OSA (n=96), who were allocated to CPAP but were nonadherent (returned or used the device less than 3 hrs/night) at 2-yr follow-up. The reference group (n=81) included ACS patients without OSA (AHI<5/hr). Median time between the revascularization and the diagnostic sleep recordings were 56 days. The primary endpoint was the first event of MACCE (repeat revascularization, myocardial infarction, stroke and cardiovascular mortality). Median follow-up was 58.4 months. Results: The incidence of the first event of MACCE was 48 (27.6%) in OSA patients versus 18 (14.8%) in those with no-OSA (adjusted hazard ratio 1.93, 95% confidence interval 1.01-3.66; p=0.045). Conclusions: OSA is an independent risk factor for MACCE in revascularized patients with ACS. Clinical trial registration:NCT00519597 Funding: The Swedish Research Council, ResMed Foundation.