How Sleep Apnea Can Lead to Dangerous Aneurysms: Insights from University of Missouri

Researchers from the University of Missouri School of Medicine and NextGen Precision Health have found that obstructive sleep apnea may increase the risk of developing abdominal aortic aneurysms. This condition occurs when the aorta, the major artery, expands and can potentially rupture, causing severe internal bleeding.

Obstructive sleep apnea is a chronic disorder where patients stop and start breathing while sleeping, increasing the risk of cardiovascular complications. The study, using mouse models, showed that intermittent hypoxia—periods when the body doesn’t get enough oxygen—caused by sleep apnea can weaken the aorta, especially in patients with additional metabolic issues like obesity.

“Chronic intermittent hypoxia by itself is not enough to cause abdominal aortic aneurysms, but for a patient with obstructive sleep apnea who also has additional metabolic problems like obesity, our findings suggest it may help degrade aortic structures and promote aneurysm development,” said Luis Martinez-Lemus, a professor of medical pharmacology and physiology.

Intermittent hypoxia happens during obstructive sleep apnea when throat muscles relax and block the flow of air into the lungs. The loss of oxygen triggers certain enzymes called MMPs, which can degrade the extracellular matrix, weakening the aorta.

“Patients with abdominal aortic aneurysms usually don’t notice any symptoms, except for some back and belly pain, until the aneurysm bursts. Once that happens, it’s crucial to get the patient to surgery quickly so doctors can repair the aorta,” said Neekun Sharma, the lead author of the study. “Learning how these aneurysms develop can help us find ways to monitor or slow down their progression, especially for patients who have obstructive sleep apnea.”