One of the keys to heart health can be found beneath the covers: The American Heart Association (AHA) recently added sleep to its checklist of what’s important for a healthy heart.
Sleep now joins physical activity, diet, weight, blood sugar, cholesterol, blood pressure, and nicotine exposure in what the AHA calls Life’s Essential 8™.
“Sleep is something you can do on an individual level to potentially protect or improve your heart health,” says Dr. Marwah Abdalla, a cardiologist at NewYork-Presbyterian/Columbia University Irving Medical Center. “Growing evidence shows that not getting enough sleep, or poor sleep quality, can lead to problems like high blood pressure or heart disease.”
Unfortunately, many people are not getting enough sleep: Almost half of all Americans say they feel sleepy during the day between three and seven days a week, according to the National Sleep Foundation (NSF), which recommends between seven and nine hours of sleep a night for healthy adults and between nine and 13 hours for children, depending on their age. More than 35% of adults in the United States report sleeping less than seven hours a night.
“We live on the edge in terms of sleep,” says Dr. Ana Krieger, director of the Center for Sleep Medicine at NewYork-Presbyterian/Weill Cornell Medical Center and Weill Cornell Medicine. “We need to make sleep a priority.”
How can you prioritize sleep and, in turn, help your heart? Health Matters spoke to Dr. Krieger and Dr. Abdalla to learn more about the link between sleep and heart health and ways to improve your sleep.
Sleep Apnea’s Impact on the Heart
One of the biggest threats to sleep and heart health is a common sleep disorder, obstructive sleep apnea (OSA), which occurs when the muscles in the back of your throat relax too much and narrow your airways, causing you to repeatedly stop and start breathing while you sleep. OSA is estimated to affect 2% to 9% of adults in the United States, though many cases go undiagnosed, according to the NSF.
The frequent drops in oxygen “can lead to all sorts of stress on the body, including damaging the vessels that supply blood to the heart, and can cause direct injury to the heart itself,” says Dr. Abdalla, who is also the Florence Irving Associate Professor of Medicine at Columbia University Vagelos College of Physicians and Surgeons. “OSA can also lead to a type of high blood pressure that affects the arteries in the lungs and right side of the heart, called pulmonary hypertension, and can cause heart failure.”
A lack of oxygen affects every organ, including the mechanics of the heart. “The heart and lungs share space in the chest wall, so as the lungs labor to breathe, the heart is also subjected to that physical stress, which can thicken the heart muscles and affect the function of the heart,” says Dr. Krieger, who is also chief of the Division of Sleep Neurology and a professor of clinical medicine in the departments of medicine, neurology and genetic medicine at Weill Cornell Medicine.
Shallow and forceful breaths wake up the brain to restore breathing, disrupting the sleep cycle and adding stress to the body. “By waking up, the brain now releases adrenaline and stress hormones to restore respiratory function, open up the airway muscles, and get you to breathe normally,” says Dr. Krieger. “This stresses the heart, increasing your heart rate and blood pressure.”
Sleep apnea increases the risk of developing blood clots, according to research led by Dr. Krieger. “We found that people, even with mild degrees of sleep apnea, have platelets that tend to stick to each other, which can lead to clotting,” she says. “This can be a contributing factor to cardiovascular disease in patients with sleep apnea.”
