Scientists have long known that obstructive sleep apnea, a disorder that often causes snoring, can increase your risk of cardiovascular diseases, but they didn’t know exactly why. Now, a team of doctors at Columbia University has pinpointed a defined chain of events that explains how this damage might occur, and found that some commonly prescribed anti-cholesterol drugs may help to prevent it.
The research team at Columbia wanted to figure out how it was that interrupted breathing was affecting the cells that line blood vessels, which is often where cardiovascular damage begins. They extracted these cells from the arms of 76 patients with obstructive sleep apnea and a further 52 others who didn’t have the sleep disorder.
They found that those with sleep apnea had a much higher level of a protein called CD59. This butterfly-shaped protein guards cells from attack by the body’s own immune system. However, on closer inspection, the researchers discovered that the CD59 of people with sleep apnea had been pulled inside the cell, instead of guarding the cell’s surface, leaving the cell vulnerable to attacks from the immune system.
These damaged cells, in turn, would be more likely to obstruct blood flow — the first such cellular explanation of how obstructive sleep apnea may cause so many serious heart problems.
But one group of snorers didn’t have these abnormal CD59 effects. Five of the sleep apnea patients who happened to be taking statins – drugs that lower cholesterol – had cells that looked just as healthy as the cells of people without sleep apnea. That suggests that statins could help protect apnea patients from cardiovascular trouble.
“This is a great start to try to understand the damage that sleep apnea does, particularly when left untreated as is so very often the case” said Dr. Shalini Paruthi, a sleep medicine expert at Saint Louis University.
Paruthi added that this damage to blood vessels is just one of the risks posed by sleep apnea. “We often run into the myth that snoring’s OK,” she said. “But it’s not OK. It might be the sign of something very dangerous.”
Untreated obstructive sleep apnea increases the risk of heart disease, stroke, high blood pressure and diabetes, as well as memory and thinking trouble.
Another new study states that more half of those diagnosed with sleep apnea fail to stick with the standard treatment for the condition, which traditionally has been the CPAP mask, and most people aren’t given additional options, even when they can’t tolerate the treatment.
Obstructive sleep apnea probably affects between 5% and 7% of the U.S. population, the researchers said. The condition is usually diagnosed during a sleep study that measures how many times someone stops breathing (apnea) or has shallow breathing with a drop in blood oxygen (hypopnea) for at least 10 seconds during each hour of sleep.
The study authors reviewed the medical records of just over 600 people. All of them had been diagnosed with obstructive sleep apnea and were immediately prescribed CPAP but just 42% began using it regularly as directed. Only about a third of those remaining, who weren’t using CPAP, were referred for an alternative to help them manage their sleep apnea.
Dr. Michael Thorpy, director of the Sleep-Wake Disorders Center at Montefiore Medical Center in New York City, said this reflects the difficulty of having patients use CPAP. “It is not an easy treatment for a lot of patients to sleep with a machine at night, and it requires some work and effort to get patients to become compliant,” he said.
Respiratory therapists or other providers can help patients with alternatives if a patient is having trouble with CPAP, said study author Dr. Alan Kominsky, Assistant Professor of Surgery at Cleveland Clinic in Ohio. “For some, CPAP is the only appropriate treatment, but others may have additional options, including dental devices or surgery”, Kominsky said.
“Oral devices are by far the best for those with mild to moderate sleep apnea/snoring, and will prevent and control this dangerous condition”.