Sleep is vital for overall health, but if you have
obstructive sleep apnea, you can slumber for more than eight hours and still wake up not feeling refreshed.
Because obstructive sleep apnea causes repeated pauses in breathing, your brain wakes you up briefly to reopen your airway. This repeated pattern of sleep interruptions, which last 10 seconds or longer and occur at least five times in an hour, can limit your ability to get the deep, restful sleep you need.
Adequate sleep means quality sleep, not just quantity, says Raj Dasgupta, MD, a pulmonary critical care and sleep medicine specialist at Huntington Health, a Cedars-Sinai affiliate, in Pasadena, California. “Someone may be getting seven to eight hours of sleep but still feel tired, because they’re not going into deep sleep,” he says. “We all need deep sleep and REM sleep to rejuvenate.”
1. Sleep Apnea May Harm Your Heart Health
Sleep apnea has been linked to heart conditions, such as
heart attacks, heart failure, and
irregular heartbeat. If you have sleep apnea, you stop breathing when you sleep and oxygen drops, activating the body’s “fight-or-flight” stress response. This causes heart rate and blood pressure to spike rapidly as you gasp for air, leading to chronic hypertension and heart strain over time, Dr. Dasgupta says.
Sleep apnea also reduces oxygen levels in the blood, limiting the supply that goes to vital organs, he notes. Your heart, like your other organs, needs oxygen to function properly.
“This reduced oxygen triggers inflammation that can harm blood vessels and the heart, contributing to conditions like atherosclerosis (plaque buildup) and cardiovascular disease,” Dasgupta says.
2. Sleep Apnea May Increase Stroke Risk (and Vice Versa)
It’s unclear whether sleep apnea or stroke comes first, but experts caution that one condition could lead to the other.
For example, research has shown that sleep apnea is prevalent among people who’ve had a stroke. As many as 70 percent of them have the sleep disorder. At the same time, sleep apnea seems to be a high risk factor for stroke.
Both sleep apnea and stroke share a number of risk factors, including diabetes, hypertension, and obesity. Sleep apnea is strongly associated with
atrial fibrillation (a potentially dangerous form of irregular heartbeat), congestive heart failure, coronary artery disease, and diabetes, which are all risk factors for stroke.
3. Sleep Apnea May Cause Weight Gain
Not everyone who is overweight has sleep apnea, but people with
obesity are more likely to be diagnosed with the sleep disorder. And if you have sleep apnea, you’re also at risk of gaining weight.
What’s behind the
obesity–sleep apnea link? When you gain weight, fat can accumulate in the neck area and obstruct breathing, leading to sleep apnea.
Plus, Dasgupta says, when you don’t get enough sleep, your body doesn’t produce enough leptin, an appetite-regulating hormone that helps reduce hunger. The lower the leptin levels, the harder it is to control appetite and lose weight, he explains.
Sleep apnea may also increase your risk of excessive daytime sleepiness, which may decrease physical activity levels and lead to weight gain. Losing 10 percent of your body weight can make sleep apnea less severe.
4. Sleep Apnea Increases the Risk of High Blood Pressure
When you stop breathing and oxygen levels fall, your brain sends a message to increase stress hormones in the body such as cortisol. This causes blood vessels to constrict and the heart to pump harder in an effort to increase the amount of oxygen available to the heart and brain. But these changes also cause intermittent increases in blood pressure, raise your risk of
hypertension, and place significant stress on your cardiovascular system.
If you have sleep apnea and high blood pressure, it’s important to talk to your healthcare provider to make sure the sleep condition is treated. Treatment of sleep apnea is an important part of managing hypertension.
5. Sleep Apnea Raises Type 2 Diabetes Risk
Sleep apnea may interfere with the body’s ability to regulate and metabolize glucose (sugar), which can increase your risk of developing insulin resistance and
type 2 diabetes. That’s because sleep apnea limits the amount of time you spend in deep sleep, which is thought to be an important process for glucose regulation in the body.
The reverse is also true: If you have diabetes, you’re more likely to have sleep apnea. According to research, as many as 80 percent of people with type 2 diabetes also have obstructive sleep apnea, and the more severe the symptoms, the higher the odds of uncontrolled glucose levels.
6. Sleep Apnea Increases the Risk of Metabolic Syndrome
Research shows a connection between sleep apnea and
metabolic syndrome, the name for a group of risk factors that increase the risk of diabetes, heart disease, stroke, and other health problems. The relationship appears to be bidirectional, with each condition increasing the risk and severity of the other. Sleep disruptions can raise stress hormones, worsen insulin resistance, and promote inflammation, all of which contribute to metabolic syndrome. At the same time, excess weight and metabolic dysfunction can further narrow airways and exacerbate sleep apnea.
According to the National Heart, Lung, and Blood Institute, if you have three of the following risk factors, you have metabolic syndrome:
- Abnormal cholesterol levels
- High blood pressure
- High blood sugar
- High fasting blood sugar (a test done after not eating anything for at least eight hours)
- Increased waist size or excess abdominal fat
7. Sleep Apnea Can Affect Your Brain
It’s not just your body that sleep apnea can negatively affect, but your cognitive function, too. Sleep apnea has been associated with cognitive disorders, such as a decrease in attention and concentration, impaired motor skills, and even poor memory.
Research also suggests untreated sleep apnea is linked to a heightened risk of
Parkinson’s disease, a movement disorder characterized by symptoms like tremors and impaired balance and coordination. Lack of oxygen due to sleep disturbances can lead to impaired neuron functioning, which might explain the connection, researchers say.
Plus, sleep apnea can hurt your head — literally. Because sleep apnea limits the amount of oxygen that goes to the brain, you can wake up with a headache, Dasgupta says.
8. Sleep Apnea Is Linked to Depression and Anxiety
Research has shown a strong link between obstructive sleep apnea and
depression, regardless of factors such as age, body mass index, and sex.
One study using data from the National Health and Nutrition Examination Survey found that adults in the United States with sleep apnea are more likely to have depressive symptoms. And the severity of sleep apnea symptoms correlates to the severity of depression. While scientists don’t fully understand what causes this increased risk, lifestyle factors such as excessive weight, as well as disruptions in the natural sleep-wake rhythm, are thought to play a role.
Treatment for sleep apnea could alleviate the symptoms of depression. One study, which found that depression and
anxiety were prevalent in people with obstructive sleep apnea, concluded that improving symptoms of obstructive sleep apnea with continuous positive airway pressure (CPAP) therapy decreased the severity of depressive and anxiety symptoms.
9. Sleep Apnea Increases the Risk of Glaucoma
According to the American Academy of Ophthalmology, people with sleep apnea are more likely to develop
glaucoma, an eye disease that can eventually cause vision loss, than people who don’t have the sleep condition.
It’s not yet fully understood how sleep apnea may cause glaucoma. But as with other health problems associated with sleep apnea, researchers hypothesize that the eye disorder could stem from decreased levels of oxygen circulating in the blood.
10. Sleep Apnea Raises the Risk of Accidents
In addition to the health effects of inadequate sleep caused by sleep apnea, the condition has been shown to increase the risk of accidents. One review of studies on the frequency of car accidents involving people with daytime sleepiness or sleep apnea found that people with sleep apnea were more than twice as likely to be involved in a car accident.
“One of the ways sleep apnea presents is as excessive daytime sleepiness,” Dasgupta says. “People may fall asleep behind the wheel or experience microsleep” — brief moments of sleep that last 1 to 30 seconds that you may not even realize are happening.
If you suspect you have sleep apnea, it’s important to be treated as soon as possible. If you’ve been diagnosed with sleep apnea but continue to experience symptoms, such as excessive daytime sleepiness, talk to your doctor about whether you should try a new treatment.
The good news is that sleep apnea can be treated, which reduces the related health risks, Dasgupta says. Some people may be reluctant to go see a doctor and have a sleep study done, assuming they’ll be hooked up to monitors and machines at a sleep center, he says. But the diagnosis process is much easier than it was in decades past.
“Today, a sleep study is not the Frankenstein’s monster, with tubes coming out, [that] you might picture,” Dasgupta says. “You can do a home sleep study in your own bed.”
The Takeaway
- Obstructive sleep apnea causes repeated pauses in breathing during sleep, preventing deep, restorative rest and increasing the risks for serious health conditions such as heart disease, high blood pressure, stroke, diabetes, and metabolic syndrome.
- Uncontrolled sleep apnea can contribute to anxiety, cognitive decline, depression, glaucoma, and weight gain and even raise the likelihood of accidents due to excessive daytime sleepiness.
- Effective treatments, such as CPAP therapy, can reduce many of these risks, helping improve both sleep quality and overall health.
