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Already a multi-tool smart device, the Apple Watch got a much talked about feature last month: an app that detects sleep apnea.
Sleep apnea is a disease in which the muscles in the throat relax excessively, causing the airway to collapse and stopping breathing during sleep. It can cause loud snoring that the sleeper himself may not be aware of. Your partner or roommate is usually the first to notice the problem.
This condition is thought to be associated with a number of health problems, primarily wear and tear on the cardiovascular system, such as high blood pressure, stroke, heart attack, heart failure, and heart rhythm problems such as atrial fibrillation. I am. It is said to be associated with dementia and daytime sleepiness. People with sleep apnea are also more likely to be involved in a traffic accident.
Millions of people are thought to suffer from this breathing disorder but remain undiagnosed, and experts say this new app could be a valuable tool to guide people through medical care. It states that there is. Sleep apnea notifications will be available on the latest Series 10 Apple Watch and some older models after a software update.
However, like any type of new technology, sleep apnea features have limitations and may have unintended consequences, such as poor sleep if you focus too much on information or worry about the outcome. there is.
“We’re seeing this phenomenon called orthosomnia, where people worry too much about their sleep data and how to maximize and improve their sleep, and they sometimes go to extremes. ,” said Dr. Robson Capasso, director of sleep surgery at Stanford University School of Medicine.
In search of the perfect night’s rest, you may end up resorting to dangerous supplements or extreme diets.
However, a new way to track your sleep doesn’t have to be a source of stress.
“We feel like this is a great tool. We just need to implement it correctly,” Capasso said.
The new Apple Watch feature uses the device’s accelerometer to measure movement, which Apple says is so sensitive that it can detect even the slightest movement of the wrist, equivalent to breathing at night. That’s what it means.
However, this is an opt-in feature, so you must turn it on for it to start working.
To detect sleep apnea, the watch measures breathing problems during sleep over a 30-day period. If there are at least 10 sessions with respiratory arrests, and at least 5 of them have an unusually high number of arrests, the watch will send a notification to the user.
How well does this feature work?
Apple tested it on about 1,500 people, some of whom were breathing normally during sleep, and others who had varying degrees of sleep apnea. Each wore the watch for at least 30 nights and conducted a more traditional home sleep study with monitors that recorded many factors such as nasal pressure, blood oxygen, body position, breathing effort, pulse, and leg movement. Went there at least 2 nights.
Researchers used this home sleep study data to determine each person’s apnea-hypopnea index, or the number of times per hour that their breathing stopped or decreased. The researchers then compared the watch’s performance to measurements taken during sleep studies.
In general, Apple’s tests found that the watch detected all degrees of sleep apnea about 66% of the time. It detected severe sleep apnea more accurately and correctly alerted users about 89% of the time. It correctly alerted users to moderate breathing problems about 43% of the time.
Apple said it tweaked the watch’s algorithms to avoid false positives that could scare users, and it appears to be working. The new alerts did not 100% notify regular sleepers that they had sleep apnea.
So if you receive an alert, you can be fairly confident that the results are real and that follow-up with your GP or sleep specialist is required. On the other hand, not receiving an alert does not necessarily resolve the issue. You may still have sleep apnea, especially if you have other suggestive symptoms.
The company’s research has not been peer-reviewed by outside experts or published in medical journals. However, the U.S. Food and Drug Administration approved the sale of the Apple Watch’s sleep apnea feature in mid-September.
There are other wearable devices touted to help people figure out if they have sleep apnea, but the fact that this is Apple’s entry into the market is drawing attention.
“This came up a lot in our conversations,” said Dr. Jing Wang, clinical director of the Mount Sinai Integrative Sleep Center. “I’ve become more aware.”
Wang says the way the clock works is different from the steps she takes to make a diagnosis. The watch relies on wrist movement, but she starts with symptoms.
“What else have you experienced other than what your watch said or your tracker said?” Wang said.
One thing to note is that the watch doesn’t ask about symptoms. Some Apple Watches also no longer use the discontinued pulse oxygen feature due to an ongoing patent dispute.
According to Wang, typical causes of sleep apnea include loud snoring (although not everyone who snores has apnea), a partner who is having trouble sleeping due to noise, or a bedmate. Examples include patients who have difficulty sleeping at night and patients with sleep apnea syndrome. Some people report feeling suffocated or suffocated when they wake up, while others say they wake up tired or feel tired during the day. Morning headaches, high blood pressure and memory problems can also occur, she says.
After this conversation, she will order a sleep study if deemed necessary. These can be done at home or in a sleep lab, but usually require an overnight stay in a hospital or sleep center. Sleep studies record multiple variables such as blood oxygen, breathing rate, cessation of breathing, and nighttime awakenings.
The Apple Watch has some of these features, but the company didn’t factor them into the sleep apnea feature. Had they done so, they might have been able to better detect mild and moderate apnea cases, said cardiologist Dr. Eric Topol, founder and director of the Scripps Translational Research Institute. say.
“If their watches had built-in pulse oximetry (which is now missing), they would have had useful data, at least for people other than people of color,” Topol said in an email. I wrote it. Research shows wearable devices that detect oxygen, called pulse oximeters, are less accurate in people with darker skin, suggesting better devices tested on more diverse populations is required.
“Unlike home tests or sleep labs, where oxygen saturation is measured continuously, the Apple watch algorithm relies on accelerometer measurements of movement, which explains the lower sensitivity.”
Stanford’s Capasso said it may not be such a bad thing that the clock isn’t as sensitive.
Even when studying perfect sleep, the answer is not clear. The apnea-hypopnea index (AHI), a key metric in sleep studies, does not necessarily correlate with symptoms, he said. Also, not all cases of sleep apnea need to be treated.
Capasso says if a patient experiences repeated symptoms of respiratory interruption, He knows that if there is a significant drop in oxygen, treatment with a continuous positive airway pressure machine (CPAP) is necessary.
This machine is a “glorified air compressor” that sends a steady stream of air through your mask to keep your airways open while you sleep.
“There is a lot of evidence that these patients who have frequent hypoxia are more closely correlated with future clinical outcomes, especially cardiovascular outcomes,” he said.
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If you have an AHI that falls into the mild to moderate category, and you also experience symptoms of daytime sleepiness or brain fog, you may also want to try CPAP.
However, not everyone can succeed with these machines. Capasso said half of the patients prescribed the treatment do not follow the treatment as intended.
For people with mild apnea, the key to better rest is to do other things, such as losing weight (overweight and obese people can often solve the problem) and improving poor sleep hygiene. It may be an option.
“In many cases, just changing your sleeping habits is enough,” he says.
For young adults with sleep apnea who are not overweight, we may also look at anatomical features such as the size of the jaw or tonsils, which may also be a factor.
Ultimately, he says, consider the age of the patient and the severity of the symptoms when deciding how aggressively to treat.
Capasso believes Apple Watch alerts could be useful for people who live alone or don’t have easy access to sleep research or experts.
“This could be a very good screening tool,” he said.
