Can Sleep Disturbances Cause Increased Stroke Risk?

Not getting enough sleep? Feeling tired and devoid of energy as a result?

That may not be all you have to worry about. There are various epidemiologic studies associating stroke with poor sleep, the latest being a study published in the April 5, 2023 edition of the journal Neurology which associates poor sleep with stroke risk.

Sleep Disturbances and Health

The Neurology study author, Christine McCarthy of the University of Galway in Ireland, noted having five of the following sleep symptoms could raise your risk of stroke - snoring, snorting, tossing and turning, napping for a long time during the day, waking up during the night, and sleeping too little or even too much.

Baystate Health neurologist Dr. Karin Johnson, Medical Director of Baystate Health Regional Sleep Program and Sleep Section Chair of the American Academy of Neurology, who has conducted her own sleep research, agrees with the findings that have also been identified in previous research. Dr. Johnson said when patients see her for possible sleep disorders, she explains to them that the dangers of not getting enough sleep or poor-quality sleep can lead to not only stroke, but many chronic health problems such as high blood pressure, diabetes, heart disease, kidney disease, obesity, and depression.

“When it comes to sleep and stroke risk, too little, too much sleep, or poor quality sleep from disorders like obstructive sleep apnea are all factors,” Dr. Johnson said.

The most common type of stroke (also called transient ischemic attack or cerebrovascular incident) occurs when blood vessels to the brain are blocked, preventing the brain from getting oxygen and nutrients from the blood needed to keep brain cells alive Poor sleep increases risk factors for stroke including obesity, high blood pressure, high cholesterol, inflammation, and diabetes, and increases the chance of blood clots forming. Poor sleep also affects the clearance of toxins from our brain through the glymphatic system, which is also associated with Alzheimer’s and dementia.

Sleep Apnea and Stroke Risk

In her own research dating back to 2010 in the Journal of Clinical Sleep Medicine, Dr. Johnson’s data showed that obstructive sleep apnea (OSA) is found in 72% of all stroke patients including those with mini-strokes, otherwise known as transient ischemic attacks, which can be a warning of a larger stroke to come. During sleep a person’s airways narrow, which in patients with OSA leads to blocked or disrupted airflow to the lungs. This can cause drops in oxygen levels or sleep disruptions throughout the night that can raise our heart rate and blood pressure and cause inflammation. Other studies have shown that even after adjusting for other risk factors, people with OSA have about double the risk of having a stroke.

Treatments for OSA include using a machine (called a CPAP or continuous positive airway pressure machine) that delivers air pressure through a mask to keep your upper airway passages open, as well as other air pressure devices, and special oral appliances available from some dentists. Baystate also offers a new alternative to CPAP that works inside your body while you sleep. Called Inspire, the implantable device controlled with a remote opens your airway while you sleep, allowing you to breathe normally and sleep peacefully.

Sleep Duration & Quality Impacts Stroke Risk

Dr. Johnson noted that adults who sleep less than seven hours per night are more likely to have a stroke, and the risk increases as average sleep time shortens. Making sure to prioritize sleep and allow enough time to get the right amount of sleep before you need to get up in the morning is important. Some people want to sleep longer, but just can’t due to insomnia. For those with racing thoughts, cognitive behavioral therapy for insomnia can be very helpful. Middle of the night awakenings may be due to OSA or another untreated sleep disorder.

A 2019 study in the journal Neurology also found that sleeping nine or more hours each night had a 23% higher risk of stroke than those sleeping less than eight hours each night. Stroke risk was 25% higher among those who took midday naps for at least 90 minutes compared with those napping for less than 30 minutes. This is likely because sleeping too much often is a sign of an untreated sleep disorder like OSA.

According to the article “Sleep and Stroke” published in the May 2, 2019 issue of the journal Stroke, despite estimates of greater than 50% prevalence of sleep disorders after stroke, only about 6% of stroke survivors are offered formal sleep testing and an estimated 2% complete such testing in the three-month post-stroke period.

Getting a Good Night’s Sleep, for Your Health

Dr. Johnson and the American Academy of Sleep Medicine offer the following additional tips on how to get a good night’s sleep:

• Avoid nicotine, alcohol, food or drinks that contain caffeine, and any medicine that has a stimulant prior to bedtime.
• Follow a consistent bedtime routine.
• Establish a relaxing setting at bedtime.
• Avoid any rigorous exercise within two hours of your bedtime.
• Make your bedroom quiet, dark and a little bit cool.
• Don’t watch the clock at night, but use an alarm to help wake you up.
• Get up at the same time every morning.
• Avoid electronics and bright lights in the evening.

Dr. Johnson noted the importance of sleep health was endorsed by the American Heart Association who in 2022 added sleep health as one of Life’s Essential 8 to prevent stroke and heart disease along with nutrition, exercise, smoking cessation, blood pressure, cholesterol and glucose control and weight loss. Because poor sleep affects all these other pillars of health, sleep is really the “bed”-rock of health.

If you struggle with poor sleep, not enough sleep, too much sleep, or any other sleep-related symptoms, reach out to our Neurodiagnostic and Sleep Center team about testing and treatment options.