How Does Sleep Help Your Heart?

We know that sleep is important. A good night’s rest keeps you alert and restores memory. It strengthens your immune system and helps guard against illness. But did you know that sleep also protects your heart?

Last year, the American Heart Association (AHA) added sleep duration to its Life’s Essential 8 checklist, joining diet, exercise, and smoking cessation, among other critical lifestyle measures necessary to maintain a healthy heart.

“Sleep gives your body an important chance to rest and recuperate,” explains Mark Benson, MD, PhD, director of Cardiovascular Disease Prevention in BIDMC’s CardioVascular Institute (CVI). “For example, a person’s heart rate and blood pressure drop while sleeping as their breathing becomes stable and regular.” Getting seven to nine hours of sleep each night also helps individuals more effectively manage their weight, blood pressure, and cholesterol, all of which help protect heart health.

But more than one in three individuals say they don’t get the recommended amount of sleep. “While a day or two of missed sleep is not a problem, over time, getting too little sleep can put individuals at greater risk for hypertension, heart disease, heart attack, or stroke,” says Benson.

What Sleep Conditions Can Impact My Heart Health?

Sleep disorders, including insomnia and sleep apnea, affect millions of individuals and are often linked to high blood pressure and heart disease. According to the Centers for Disease Control and Prevention (CDCP) as many as one in two adults experience short-term insomnia at some point, and one in 10 may deal with moderate or greater chronic insomnia. “Insomnia refers to trouble falling asleep, staying asleep, early morning awakening, or some combination,” says Robert Thomas, MD, clinician and researcher in BIDMC’s Sleep Disorders Center. “Insomnia has a significant impact on a person’s daytime functioning,” he says, adding that over time, this sleepless pattern can lead to higher stress levels and less motivation to exercise or eat a healthy diet.

Sleep apnea is also a widespread problem. Characterized by snoring, gasping for breath, and daytime sleepiness, sleep apnea develops when breathing repeatedly stops and starts during sleep.

“Repeated pauses in breath in patients with sleep apnea not only interrupt sleep, but also deprive the body of oxygen, causing significant stress to the cardiovascular system,” says Patricia Tung, MD, an electrophysiologist in the CVI’s division of Arrhythmia Services. “It’s estimated that patients with sleep apnea are two to four times more likely to develop heart arrhythmias [abnormal heartbeats] than people who don’t have sleep problems.”

What Treatments Are Available For Sleep Apnea?

Sleep apnea lies on a spectrum, with obstructive sleep apnea at one end and central sleep apnea at the other. Many patients experience varying degrees of both types. Obstructive sleep apnea develops when throat muscles relax or narrow and block the upper airway. This problem is often improved by weight loss or lifestyle adjustments, such as not sleeping on your back. In more serious cases, a mechanical support device such as a CPAP (continuous positive airway pressure) machine or lower jaw brace keeps the upper airway open.

In contrast, central sleep apnea results from the brain sending stop-start signals to the muscles that control breathing and is more difficult to treat. “Unlike obstructive sleep apnea, central sleep apnea is not the result of a single area of blockage,” explains Anjali Ahn, MD, clinical director of Pulmonary and Sleep Medicine at BIDMC. “It’s an overall unstable breathing pattern, almost like having an overly sensitive thermostat that fluctuates dramatically from high to low.” An estimated 40 percent of patients with congestive heart failure have central sleep apnea.

Last year, CVI’s Arrhythmia Service and the Sleep Disorders Clinic, began offering a procedure known as phrenic nerve stimulation treatment for selected patients with moderate to severe central sleep apnea.

“We position a stimulating wire inside the chest by way of a patient’s blood vessel, similar to a pacemaker insertion,” says Tung. The device works by stimulating the phrenic nerve in the chest to send signals to the diaphragm, the large muscle between the chest and abdomen that drives much of breathing. “This eliminates fluctuations in breathing and thereby prevents the development of central apnea,” says Ahn. “We’re still at an early stage in offering this treatment, but thus far, patients have reported improved sleep and quality of life.”

How Can I Get Better Sleep?

For many patients, lifestyle changes can help lead to improved sleep. Thomas recommends the following:

Maintain a regular sleep schedule. As much as possible, go to bed at the same time each night and get up at the same time each morning, even on the weekends.

Get natural light exposure in the morning. Early in the day, expose yourself to as much natural light as possible, for example, by taking an early walk or just turning on the lights soon after waking up.

Cut back on artificial light in the evening. “Within a few hours of bedtime – 8 pm is a good rule of thumb -- turn the lights down and dim the brightness on your phone or device,” says Thomas. “Then once you go to bed, you really want as close to absolute darkness as you can get.”

Eat heavy meals well before bedtime. “The earlier you can eat, the better,” says Thomas. “If at all possible, try and finish dinner by 6 pm, 7 pm at the latest, as there may be benefits to having a 12- to 14-hour food-free period.” Skipping alcohol and foods high in fat and sugar can also lead to improved sleep.

Avoid sleeping on your back. “Your breathing is impaired when you are lying on your back, regardless of whether or not you have sleep apnea,” says Thomas. “It’s better to sleep on your side.”

When Should You See a Doctor For Lack of Sleep?

If you have been experiencing disrupted sleep, daytime tiredness, or other symptoms you think may be associated with a sleep disorder, Thomas recommends that you consult with your primary care physician to explore a possible diagnosis. “Treatment for sleep apnea and other conditions can greatly improve a person’s quality of life,” he says. If it is determined that you have a sleep disorder, you and your doctor should further discuss a plan to address your possible risk of cardiovascular disease.

Learn more about the BIDMC Sleep Disorders Center and the Cardiovascular Disease Prevention Clinic.