About 38 percent of people with sleep apnea also experience episodes of sleep paralysis — a frightening disorder in which people can’t move their body when transitioning in or out of sleep. While being unable to move is scary enough, some people also see vivid hallucinations known as “sleep demons.” It’s enough to make some people want to avoid sleeping altogether.

But what’s the connection with sleep apnea? These conditions share few overlapping symptoms and have distinct risk factors. In this guide, we’ll explore each disorder and explain why so many people with sleep apnea also experience sleep paralysis.

What Is Sleep Apnea?

People with sleep apnea occasionally stop breathing while asleep. This happens because the airways close (obstructive sleep apnea, or OSA) or because the breathing muscles don’t receive the correct signals from the brain (central sleep apnea, or CSA).

Sleep apnea causes people to wake up frequently in the middle of the night in order to restore their breathing. Some people don’t notice these interruptions, but they can still negatively affect sleep quality and cause excessive daytime sleepiness, fatigue, or exhaustion.

What Is Sleep Paralysis?

Sleep paralysis occurs when your mind is in one sleep phase but your body is in another. People with sleep paralysis can’t move their body right before falling asleep or right after waking up. They may feel like they can’t breathe or speak.

Some also experience hallucinations, sense a dangerous presence in the room, or feel a suffocating pressure on their chest. Sleep paralysis symptoms can last for seconds or minutes.

It’s normal to not be able to move your arms or legs during the rapid eye movement (REM) sleep phase. Known as REM atonia, this temporary muscle paralysis prevents us from rolling off the bed or acting out our dreams.

Most people never consciously experience this immobility because the brain syncs into the same sleep phase as the body. When the muscles “turn off” in REM sleep, the brain starts to dream.

Sleep paralysis can be a scary experience. Imagine hallucinating spiders or dark shapes in the room and being unable to move or shout. Many people report feeling frightened or anxious during an episode, and some don’t want to go back to sleep because they’re worried about having another episode.

What’s the Connection Between Sleep Apnea and Sleep Paralysis?

People with sleep apnea are at a higher risk of experiencing sleep paralysis. Nearly 2 in 5 people with sleep apnea have had at least one episode of sleep paralysis. On the other hand, sleep paralysis doesn’t increase the risk of sleep apnea.

Sleeping on your back increases the likelihood of experiencing both sleep apnea and sleep paralysis. In this sleep position, your airways are more likely to narrow as soft tissues in the mouth and throat fall backward. This means you’re more likely to wake up as your oxygen levels dip — the hallmark symptom of sleep apnea.

Studies suggest the airways are also more likely to close during rapid eye movement (REM) sleep, which means you’re also more likely to wake up during this phase when you have sleep apnea.

If you also have sleep paralysis, you have trouble transitioning from REM sleep to wakefulness. When you’re waking up frequently because of sleep apnea, there are more opportunities for you to experience sleep paralysis.

What Are Some Major Differences Between Sleep Apnea and Sleep Paralysis?

Sleep paralysis may feel scarier than sleep apnea, but sleep apnea is more likely to cause negative health effects.

Sleep apnea stresses the body by raising blood pressure, blood sugar, heart rate, and stress hormones. This may explain why people with sleep apnea face an increased risk of heart attack, stroke, type 2 diabetes, and early death.

One study found that people with sleep apnea are three times more likely to die from any cause compared to people without sleep apnea. It’s rare for people to die in their sleep from sleep apnea due to choking, but it can cause heart rhythm abnormalities or cardiovascular events (stroke and heart attack) that can lead to sudden death.

In contrast, sleep paralysis isn’t considered dangerous to your physical health. People often feel like they can’t breathe during a sleep paralysis episode, but they actually are breathing — they just can’t switch from involuntary, shallow breaths to voluntary, deep breaths.

Although it doesn’t lead to physical complications, sleep paralysis may affect your mental health by causing anxiety, distress, or confusion. About 7 percent of people with sleep paralysis say it interferes with their daily life.

Different Risk Factors

Sleep paralysis has also been linked to narcolepsy, sleep deprivation, substance use disorder, certain medications, mental health conditions like post-traumatic stress disorder, and irregular sleep due to shift work. Episodes tend to be more common in people in their 20s and 30s but can happen at any age.

None of those factors increase the risk of sleep apnea. Instead, sleep apnea tends to occur in people who have obesity, large tonsils, certain heart conditions, and family members with sleep apnea. People are more likely to develop sleep apnea as they get older, but people of any age can experience it.

Signs You Might Have Sleep Paralysis and Sleep Apnea

You might have sleep paralysis and sleep apnea if you experience distinct symptoms of both conditions. Many people know they have sleep paralysis because each episode is frightening and memorable. But sleep apnea symptoms can be more subtle.

Some people with sleep apnea wake up gasping or choking. Other symptoms might be noticed by your sleep partner, such as snoring, pausing between breaths, or unusual breathing patterns.

Having a headache as soon as you wake up, sweating a lot at night, and experiencing mood changes or sexual dysfunction could also be signs of sleep apnea.

Treating Sleep Apnea and Sleep Paralysis

Talk to a healthcare provide if you suspect you have sleep paralysis, sleep apnea, or another sleep disorder. To form an accurate diagnosis, they’ll ask about your symptoms and may send you home with a device that analyzes your sleep.

In some cases, you may need to spend the night at a sleep lab so that healthcare professionals can conduct a polysomnography (sleep study) in real time.

Getting the right diagnosis ensures you get the right treatment. Obstructive sleep apnea is often treated with a continuous positive airway pressure (CPAP) machine, which helps keep the airways open.

Limited research shows CPAP therapy also helps treat sleep paralysis in some people, probably because sleep apnea is sometimes the underlying cause of sleep paralysis.

Other devices that keep the airways open include mouthpieces (also called oral appliances) and neuromuscular electrical stimulation (NMES) devices. Learning to sleep on your side or stomach may help as well.

Medications may also help, especially if they treat the underlying condition that’s causing your sleep apnea or sleep paralysis. In some cases, you may benefit from a surgery to treat sleep apnea, but there’s no corrective surgery for sleep paralysis.

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