Is obstructive sleep apnea a risk factor for the progression of thoracic aortic aneurysm? A prospective cohort study

Abstract

Obstructive sleep apnea (OSA) is associated with aortic aneurysms and it has been suggested that severe OSA furthers aneurysm expansion in the abdomen. The aim of this prospective cohort study was to evaluate whether OSA is a risk factor for the progression of thoracic aortic aneurysms (TAA).

A cohort of 245 patients with TAA underwent four annual, standardized echocardiographic measurements of the aorta and level-3 sleep studies at baseline and follow-up. The primary outcome was the yearly expansion rate of TAA in relation to the Apnea-Hypopnea-Index (AHI); the secondary outcomes included aortic events i.e. ruptures, dissections, endovascular repairs or rapid progressions of TAA. ClinicalTrials.gov Identifier: NCT02204774

Between July 2014 and February 2020 all patients completed the protocol and 73% (n=179) underwent all four measurements. At baseline, participants (85% male) had a mean age of 68±12 years, a mean Body-Mass-Index of 27±4 kg/m2, and the mean AHI was 10 (quartiles 4-21) events/hour. Average expansion rates were 0.21 (quartiles 0-0.44) mm/year at the aortic sinus and 0.12 (quartiles 0- 0.40) mm/year at the ascending aorta. In multivariate regression analysis, controlling for cardiovascular risk factors and blood pressure, the AHI remained an independent risk factor for TAA expansion (p<0.001 for the aortic sinus and ascending aorta). 8% (n=20) of participants experienced an aortic event and there was no association with OSA severity.

OSA seems to be an independent risk factor for TAA expansion. A causal relationship remains to be established in a randomized controlled intervention trial.