Impact of Obstructive Sleep Apnea on In-Hospital Outcomes of Patients with Non-ST Elevation Myocardial Infarction

Background: Obstructive sleep apnea (OSA) is one of the most common breathing disorders. There are uncertainties about its impact on the in-hospital outcomes of patients who suffer acute coronary syndromes. We studied the largest publicly available all-payer inpatient healthcare database in the United States (National Inpatient Sample) to determine the effects of obstructive sleep apnea on the in-hospital outcomes of patients admitted with non-ST elevation myocardial infarction (NSTEMI). Methods: All adult patients (age ≥ 18) admitted primarily for NSTEMI between September 2010 and September 2015 were identified in the National Inpatient Sample. They were then categorized into those with OSA and those without OSA. The main outcome was in-hospital mortality. Propensity scoring and logistic regression models were created to determine the outcomes. Results: There were 1,984,432 patients with NSTEMI (weighted estimates), 123,551 (6.23%) of who had diagnosed OSA while 1,860,881 (93.77%) did not. In-hospital mortality was significantly lower in the OSA group [2.61% vs. 3.53%, adjusted odd ratio (aOR) 0.73 and confidence interval (CI) (0.66–0.81)]. Patients with OSA were also less likely to require coronary artery bypass surgery: 13.85% and 12.77% (p-value 0.0003). The patients with OSA had higher mean hospital costs compared to the patients who did not have OSA: $17,326 vs. $16,984, adjusted mean ratio (aMR) 1.02; CI (1.01–1.02). Conclusion: In-hospital mortality was lower in NSTEMI patients with diagnosed OSA compared to patients without diagnosed OSA. This appears to contrast with the widely recognized adverse effects of OSA on the cardiovascular system.