Researchers estimate that untreated sleep apnea may raise the risk of dying from heart disease by up to five times.
Poor-quality sleep and heart disease are connected
We’ve all heard stories about super snorers, whose snorts and snores rattle windows and awaken the neighbors. Many of these people suffer from sleep apnea. In this condition, the airway becomes blocked, or the muscles that control breathing stop moving. Either way, breathing stops… and then resumes with a gasp. In the worst cases, this can happen hundreds of times every night.
Because sleep apnea sufferers are constantly awakened, they have poor-quality sleep and feel exhausted all day. They may also suffer from poor cardiovascular health. The sleep disorder is found in 47% to 83% of people with cardiovascular disease, 35% of people with high blood pressure, and 12% to 53% of people with heart failure, atrial fibrillation (a heart rhythm abnormality), and stroke. Researchers estimate that untreated sleep apnea may raise the risk of dying from heart disease by up to five times.
In sleep apnea, the airway often collapses, blocking airflow. The person awakens hundreds of times a night gasping for air. The body releases a stress hormone which, over time, may raise blood pressure and contribute to heart problems.
Poor sleep affects the heart
Obstructive sleep apnea (or OSA)—the most common form of sleep apnea—is caused when the upper airway collapses or becomes blocked during sleep. People who are obese or overweight have excess fat in their throats that can contribute to the problem, but some people with OSA are slender.
“Over time, OSA exposes the heart and circulation to harmful stimuli that may cause or contribute to the progression of most cardiovascular diseases,” explains Dr. Atul Malhotra, associate professor at Harvard Medical School and sleep specialist at Brigham and Women’s Hospital.
It works like this: When you stop breathing, your oxygen level drops. The body responds by releasing epinephrine (also called adrenaline), a stress hormone. When this happens over and over, adrenaline levels remain high. This can lead to high blood pressure.
Fortunately, several effective treatments for OSA are available. A bedside machine that provides a constant stream of air through a face mask can prevent the back of the throat from collapsing and obstructing airflow. Called continuous positive airway pressure (or CPAP), it’s the treatment of choice for OSA. Although some people have trouble adjusting to the mask, many others call it “transformative,” and say they never felt so good. Early research suggests that treating OSA with CPAP may improve heart function and lower the risk of cardiovascular complications.
Custom-made mouthpieces are also available. These devices pull the jaw forward to help keep the airway open. Disposable devices that adhere to the nostrils and pressurize the airways are in development.
For some people, losing weight, eliminating alcohol use, or stopping the use of medications that relax the muscles can improve sleep.
“The best treatment for an individual may ultimately depend on the underlying cause of the sleep apnea as determined by an expert in sleep disorders,” says Dr. Malhotra.
Heart disease affects sleep
A different form of sleep apnea, called central sleep apnea (or CSA), is often found in people with conditions that cause them to retain sodium and water, such as heart failure. Doctors suspect that some of the excess fluid enters the lungs at night, causing these individuals to awaken feeling short of breath.
“CSA appears to occur due to an unstable respiratory control system, and is probably a consequence, rather than a cause, of heart failure,” Dr. Malhotra explains.
Men, older adults, and people with atrial fibrillation, are also at increased risk for CSA.
CSA is treated through closer management of the underlying disease that is causing the problem.
Could you have sleep apnea?
An unusual breathing pattern or loud snoring often leads to a diagnosis of sleep apnea. Yet excessive daytime sleepiness—an equally common symptom—may be overlooked, misdiagnosed, or downplayed.
“It’s not normal for older people or people with cardiovascular disease to be sleepy all the time,” says Dr. Malhotra. “If you are lying in bed all day, falling asleep at inappropriate times, and have no energy, talk to your doctor about getting a sleep study. You may have a treatable condition.”
Not all snorers have sleep apnea, and other possible symptoms of it can be caused by a variety of health problems. The surest way to diagnose sleep apnea is with an overnight sleep study conducted in a sleep clinic. Throughout the night, information from electrodes placed on the head and chest are sent silently to a central station, where it is interpreted by sleep experts. Home monitoring devices are now on the market, but how well they work is an open question.