Thoracic Aortic Dissection is Associated With Severe Obstructive Sleep Apnea

Patients with thoracic aortic dissection exhibit a high apnea-hypopnea index, according to study results published in the December 15th issue of the American Journal of Respiratory and Critical Care Medicine.

Obstructive sleep apnea syndrome (OSAS) “is associated with the development of arterial hypertension, the main risk factor for aortic dissection and, during obstructive episodes of the upper airways, with marked increases in transmural pressure of the aorta wall,” Dr. Gabriel Sampol and colleagues from Hospital Universitari Vall d’Hebron, Barcelona, Spain, write.

The researchers examined the association between aortic dissection and OSAS in 19 consecutive patients with thoracic aortic dissection and 19 matched hypertensive patients. The subjects all answered clinical questionnaires and underwent polysomnography.

Snoring and nonrefreshing sleep were frequent in both groups, according to the investigators. An apnea-hypopnea index of more than 5 per hour was observed in 13 patients (68%) from each group. However, the apnea-hypopnea index was higher in patients with aortic dissection (28 versus 11, p = 0.032).

Seven (37%) patients with aortic dissection had an apnea-hypopnea index of more than 30, the investigators found, compared with one (5%) control patient (p = 0.42). Aortic dissection patients had a higher prevalence of previously undiagnosed and often severe OSAS.

“We speculate that the coexistence of OSAS may impose an additional risk of aortic dissection in predisposed patients or determine worse evolution because of the increase on aortic transmural pressure implied,” Dr. Sampol and colleagues explain. “Because effective treatment for OSAS is available, we believe its diagnosis should be considered in the overall assessment of patients with aortic dissection.”

Am J Respir Crit Care Med 2003;168:1528-1531.