Association between obstructive sleep apnea and thoracic aortic diameter: a cross-sectional study in a clinical sample.

Study Objectives: Previous studies have suggested that obstructive sleep apnea (OSA) may be associated with aortic dilatation. We aimed to further characterize the association between OSA severity with thoracic aortic diameter.

Methods: We evaluated 1470 patients attending an Australian clinic during 2014-2023 and who underwent transthoracic echocardiogram followed by polysomnographic study in the following 6 months (43.7% female, median age 65 years, median BMI 29.6kg/m). Aortic root and ascending aortic diameters were compared among patients based on OSA severity, defined by apnea-hypopnea index (AHI).

Results: OSA was observed in 90% of patients. Both aortic root and ascending aorta diameters were associated with increasing OSA severity (p<0.01). These associations remained significant when indexed for height, but not body surface area (BSA). Multivariate analysis considering age, weight, hypertension status, atrial fibrillation, and smoking history suggested an independent role of OSA on aortic dimensions in women but not in men. However, a case-control sensitivity analysis did not demonstrate a significant difference in aortic diameter between no/mild OSA compared to moderate/severe OSA.

Conclusions: This is the largest study examining the association of OSA and thoracic aortic dimensions in a clinical sample. It found a significant increase in both aortic root and ascending aorta diameters with increasing OSA severity, although this may be explained by shared risk factors such as age, BMI, hypertension, and atrial fibrillation. A minor independent association between aortic dimensions and OSA severity was observed in women but not men. Further research is warranted to explore the relationship between OSA and aortopathy.