Pulm Circ. 2021 Mar 27;11(2):2045894021996224. doi: 10.1177/2045894021996224. eCollection 2021 Apr-Jun.
Pulmonary embolism (PE) is a major cause of cardiovascular morbidity and mortality. Obstructive sleep apnea (OSA) is increasingly recognized in the aging population, especially with the rising obesity epidemic. The impact of OSA on inpatient mortality in PE is not well understood. We used the Nationwide Inpatient Sample databases from 2005 to 2016 to identify 755,532 acute PE patients (age≥18 years). Among these, 61,050 (8.1%) were OSA+. Temporal trends in length of stay, inpatient mortality, and its association with OSA in PE patients were analyzed. The proportion of PE patients who were OSA+ increased from 2005 to 2016. OSA+ PE patients were younger and predominantly men. Despite a higher prevalence of traditional risk factors for inpatient mortality in OSA+ patients, OSA was associated with a lower risk of mortality in PE patients (odds ratio, 95% confidence interval; p: unadjusted 0.56, 0.53-0.58; p < 0.0001 and adjusted 0.55, 0.52-0.58; p < 0.0001). Overall mortality and length of stay in PE patients decreased over time. Relative to OSA- patients, there was a slight increase in mortality among OSA+ PE patients over time, although the length of stay remained unchanged between the two groups. In conclusion, OSA+ PE patients had a lower inpatient mortality compared to OSA- patients despite a higher prevalence of traditional mortality risk factors. Secondary pulmonary hypertension related to OSA with preconditioning of the right ventricle to elevated afterload may potentially explain the protective effect of OSA on mortality in PE. However, mechanistic studies need to further elucidate the links behind this association.