Tens of millions of people in the U.S. and hundreds of millions of people worldwide are likely missing out on a crucial piece of health information–one that could impact their risk of Alzheimer’s, heart disease, hypertension, and change their quality of life. Sleep apnea is estimated to affect up to one billion people around the globe, but “probably fewer than 10% are diagnosed and treated,” says Atul Malhotra, Vice Chair of Medicine and a research chief for sleep medicine and pulmonary critical care at the University of California, San Diego. Which is a shame, because diagnosis and treatment can have “transformative benefits,” he tells Popular Science.
Sleep apnea is one of the most common sleep disorders, but research suggests it has wide ranging consequences, recognizing it can be a challenge, and common misconceptions might prevent sufferers from seeking treatment. Here’s what you should know, according to sleep medicine experts.
What is sleep apnea?
Apnea literally means a temporary stop to breathing. For a formal definition of sleep apnea, these cessations in airflow need to last at least 10 seconds and occur a minimum of five times every hour. The severity of a case of sleep apnea is defined by the number of apneas that happen per hour. Mild cases are considered 5-15 pauses in breathing, moderate is between 15 and 30, and above 30 is considered severe, says Indira Gurubhagavatula, a professor of medicine at the University of Pennsylvania and a member of the board of directors of the American Academy of Sleep Medicine.
When breathing stops repeatedly, people often wake up–sometimes gasping for air, and sleep becomes fragmented. It also leads to reduced blood oxygen levels, and when O2 concentrations drop, the body releases a surge of adrenaline to try to restore proper levels. Adrenaline can make it hard to fall back asleep, but the hormone also stresses the heart, brain, and other organs over time, Gurubhagavatula tells Popular Science.
“That’s why sleep apnea should be thought of as a systemic disorder,” says Allan Pack, a sleep medicine professor of medicine also at UPenn. “It affects all tissues and it can have a number of real consequences,” he adds.
Studies have linked untreated sleep apnea with an increased risk of cognitive decline and Alzheimer’s disease, cancer, heart disease, and even “all cause mortality” (i.e. general death), notes Malhotra. It’s also associated with type 2 diabetes, is considered a major risk factor for high blood pressure, and increased risk of mental health disorders like anxiety, depression, or suicidal ideation.
There are two types of sleep apnea. The most common, by far, is obstructive sleep apnea, wherein a physical blockage prevents breathing. Often, this occurs because the muscle and tissue at the back of the throat relax and fall during sleep, constricting or entirely blocking up the airway. In contrast, central sleep apnea is much more rare, occurring in less than one percent of adults, and is caused by a loss of coordination between the brain and the respiratory system.
Somewhere between 10 and 30 percent of adults are thought to have obstructive sleep apnea, depending on factors like where you live, ethnicity, and sex. It is much more common among men and risk increases with age and weight. People with obesity have a significantly higher rate of sleep apnea. About 60 to 70 percent of obstructive sleep apnea patients have obesity, says, Malhotra, a sizable proportion–but not everyone. Alcohol is also a major factor. If you have a nightcap before bed, you may be setting yourself up for disrupted nighttime breathing. Sedatives like alcohol (or even certain prescribed medications) can block the nerve that controls the tongue, notes Gurubhagavatula, leading to more blockage.
What are the signs and symptoms of sleep apnea?
The basic symptoms of sleep apnea can sound commonplace and as if they apply, at times, to nearly everyone: Things like snoring, tiredness, and moodiness. Yet there are ways to parse out your risk and to know if and when to be concerned.
Not all snoring is sleep apnea, but sleep apnea is often associated with loud, disruptive, and consistent snoring, says Gurubhagavatula. Many people snore from time to time with congestion, seasonal allergies, or alcohol consumption–but habitual snoring is worth investigating, she says.
Similarly, constant sleepiness that moves beyond occasional fatigue should be a red flag. Regularly nodding off during daytime activities or having difficulty staying awake warrants a doctor’s visit. Apnea-associated exhaustion can prove particularly dangerous If you find yourself tired and losing focus while driving, says Pack. Increased risk of car accidents is one of many downstream consequences of sleep apnea.
“85 percent of sleep apnea is missed and people don’t come forward because they assume that, ‘oh everybody snores. I’m just a little tired’, and they tend to ignore it,” she says. But “it’s really important not to ignore it.
Other common symptoms include hypertension, frequent nighttime urination (oxygen stress changes how your body processes water and sodium), irritability, cognitive impairment, routinely waking up with a start, loss of libido, and headaches. More rarely, people with sleep apnea might present with nightmares, sleep talking or yelling, or teeth clenching, Gurubhagavatula adds. Bed partners are uniquely positioned to pick up on the signs of sleep apnea, and often even note the apneas themselves. “A partner might say, ‘I hear your breathing pattern and it’s scary,’ or ‘I hear you stop breathing in your sleep,’” she says.
Ultimately, if you are experiencing symptoms and have any suspicion you might be suffering from sleep apnea, it is worth consulting a professional. “Snoring and fatigue are common, but obstructive sleep apnea is very common as well,” says Malhotra. “The bottom line is, if you’re concerned, talk to your doctor.” The good news is that sleep apnea is easily tested for and eminently treatable.
What are the treatment options?
The first step is to get tested and see if you have sleep apnea. The disorder can sometimes be confused for other issues like insomnia or chronic partial sleep deprivation, and an accurate diagnosis is key. In the past, sleep studies to evaluate for sleep apnea would require overnight stays at a sleep center or hospital. But now, many evaluations can be done at home via less intrusive, portable devices that monitor breathing, heart rate, and oxygen levels. Usually just one or two nights of observation is enough to provide a clear answer, says Gurubhagavatula.
If assessment does reveal sleep apnea, the first line of treatment is usually a continuous positive airway pressure (CPAP) machine–essentially a pump that keeps users’ airways at a high enough pressure to prevent collapse. Sleeping with a CPAP requires sleeping with a mask over your nose or nose and mouth, attached to the bedside pump. The idea can be off-putting to some–even becoming a reason to avoid seeking diagnosis in the first place, Gurubhagavatula notes.
Yet CPAP machines are a very effective, life-saving treatment that many end up acclimating to better than they expect, says Malhotra. Finding the most comfortable set-up and troubleshooting initial difficulties can require some expert interventions, but “eventually most patients can tolerate it well,” he adds.
Even for those who truly cannot adjust to a CPAP, there are other options. Oral appliances which pull the jaw forward can help. A surgery that involves implanting a hypoglossal nerve stimulating device is also effective. For mild cases, even changing your sleep position can help, as sleeping on your back can exacerbate an airway obstruction. There are tools and therapies available to assist with shifting to side-sleeping, says Pack, “though we don’t use them a lot clinically.”
Because of the link between alcohol and apnea, eliminating or cutting back on drinking can be a boon to sleep quality, Gurubhagavatula says. Similarly, discussing the side effects of any prescribed medications with your doctor is important for keeping tabs on overall health.
Finally, there’s weight loss. Bariatric surgery can significantly reduce severity of obstructive sleep apnea, or even eliminate it altogether for some. A recent study, on which Malhotra was the lead investigator, found that GLP-1 drugs like Mounjaro, Zepbound, Wegovy, or Ozempic can also alleviate moderate and severe sleep apnea for many, as they enable dramatic weight loss.
However, weight loss is not always a complete solution. About 30 percent of the GLP-1 study patients were effectively cured of their sleep apnea over the course of a year, says Malhotra, meaning the rest had some residual disease. Critically, these medications aren’t currently FDA-approved to treat sleep apnea and both GLP-1 drugs and bariatric surgeries can be costly interventions that come with their own risks and side effects that should be discussed with your doctor.
Without medical assistance, weight loss is no simple fix, Malhotra emphasizes–it’s difficult and not achievable for many. Sleep apnea itself probably makes the process a whole lot harder.
In medicine, “one of the dogmas we have is that diet, exercise, and sleep are the three pillars of health…if you ignore one, the other two will suffer,” Malhotra says. Being active and eating well become less attainable if you’re not well-rested.
It’s yet another way that better rest, and perhaps a CPAP machine, can make a world of difference, says Gurubhagavatula. If you have sleep apnea, “that CPAP machine may one day become your best friend when you see what’s on the other side, and the life you get to live with a good night of sleep.”