Sleep apnea is a potentially serious sleep disorder that affects a 25% of men and 10% of women in the U.S. RUSH sleep surgery specialist Michael Hutz, MD, describes the condition, its causes and what can be done to help those who suffer from it.
What is sleep apnea and how does it affect the body?
So there are two major types of sleep apnea. So the first one which is by far the most common is called obstructive sleep apnea. And what that means is that there's certain parts of the throat that collapse or close that obstruct or block the airway while you're sleeping.
That's the most common, the other major type is called central sleep apnea. And that's where there's essentially not a signal that's sent from the brain to the lungs to breathe while you're sleeping and that's more commonly seen in patients that have different neurologic or cardiovascular diseases.
What causes the throat to collapse during sleep?
There's a lot of different things that can cause the throat to collapse. There are different parts of the throat so some patients for instance can have big adenoids which are kind of like tonsil tissue in the back of the nose that can obstruct breathing. The soft palate and the uvula can collapse blocking the airway. Some patients have big tonsils or have the lateral walls or the side walls of the throat kind of collapsing in. For other patients the back of the throat or the back of the tongue collapses or the epiglottis collapses.
A lot of times we kind of put patients in two different categories. In my mind, patients younger than 45 a lot of times their sleep apnea is caused by some kind of anatomic obstruction so those patients might have big tonsils and adenoids which is really common in kids, or sometimes they can have underdevelopment of the jaws.
Some patients will have a narrow high arched palate, others will have kind of a backset lower jaw and it essentially makes the room too small or the airway too small. For patients older than 45, a lot of times it's physiologic and that means that the muscles of the upper airway lose muscle tone and so that causes the soft palate and the tongue base to kind of fall back and block the airway.
What are the most common symptoms of sleep apnea?
Sleep apnea is a really interesting disease because it can manifest in a lot of different ways. So some of the more common symptoms are snoring. People will witness apnea so they'll notice a pause in breathing while they're sleeping or their bed partner will notice that. Daytime sleepiness or fatigue needing naps throughout the day, some patients will wake up with morning headaches.
And then other things that are more subtle, increased urination can be frequently seen in patients with obstructive sleep apnea as well.
Can you tell us a little bit more about why frequent urination would be a part of sleep apnea?
There's a couple different theories about why that might be the case. One of the theories is that, as you're trying to breathe at nighttime and your chest is expanding and you're trying to breathe but your throat is closed or collapsed, it generates a lot of negative intrathoracic pressure or pressure within the chest and that stretches the heart itself.
And so it can stretch the atrium, which causes the body to release this hormone that basically tells the body oh, I'm fluid overloaded and so it tells the kidneys to produce more urine and pee because it thinks that you need to get off some of that fluid. And so there are a lot of patients that actually will be urinating multiple times a night and a lot of men, older men especially think it's a prostate issue. And for a lot of them it can be, but a lot of times it also is caused or worsened by obstructive sleep apnea.
Sometimes people's bed partners will notice them stopping breathing but how is sleep apnea actually diagnosed medically?
There's certain physical exam findings that we think make it more likely. Some of the data we have is men with neck sizes greater than 17 inches, women with neck sizes greater than 15 inches increases your risk for sleep apnea. Regardless of symptoms or physical exam findings, nothing is 100% indicative of sleep apnea and so really the only way to truly diagnose it is with a sleep study.
What is a typical sleep study actually like for most people these days?
A formal sleep study in the traditional sleep study is something that's done in a lab so it can be in a clinic building, a hospital building, in a private practice setting. Where the patient actually comes in in the evening, they have a bunch of different sensors so there's typically about seven different things we're measuring from brainwaves to heart rate, to oxygen levels, to body positions and movements and kind of breathing efforts. And that's really sensitive and really specific but also pretty intensive and a lot of patients had a hard time being able to fall asleep with all these wires connected to their head.
So for various reasons, the technology kind of continued to improve and now we have a lot of different types of that they're called home sleep studies. And so the home sleep studies kind of vary depending on the technology and the company but it's much more simplified where it might be wearing a little oxygen sensor on the finger. You might have a little nasal cannula on the nose and some kind of belt across the chest to measure breathing. And that at least is a good screening tool to tell you whether or not you have sleep apnea.
I will say, that if you have a high what's called a pretest probability, if someone is very likely to have pretty bad sleep apnea the home sleep study is great because even if it underestimates how bad your sleep apnea is, you'll still get a diagnosis. But for some patients where it's a lower probability that they have sleep apnea, the home sleep study can be negative but if you're really worried about it, then you would go to an in lab sleep study which is typically more sensitive.
How common is sleep apnea and who does it mostly affect?
The current demographic data we have shows that about 25% of men we think, and about 10% of women are affected by obstructive sleep apnea but it's thought that that number is probably grossly underestimating how many people are actually affected by this disease.
Traditionally, it's much more common in men than women but interestingly, a lot of women are diagnosed with snoring and sleep apnea right around menopause. So post-menopause the rates between men and women are much more similar and the thought behind that is that there's some data to show that some of the female hormones of progesterone and estrogen improve the muscle tone at the airway.
And so the thought is that when a woman goes through menopause and those hormone levels kind of precipitously drop the muscle tone drops with it. And so if a woman was compensating well with having good muscle tone all of a sudden that's gone and now when they go to sleep their tongue and their soft palate kind of falls back and then starts blocking the airway.
There's also been a stubborn misperception that sleep apnea is something that typically happens to people who are overweight. What truth is there to this perception and where does that misperception come from?
Part of it could be from some of the early descriptions of sleep apnea and so one of the first ones that we had in the literature was actually from Charles Dickens. It was from one of his first books called The Posthumous Papers of the Pickwick Club. And in that he describes this boy who's super overweight and he's falling asleep while he is awake and storing loudly.
I think nowadays we realized that he actually probably had something called obesity hypoventilation syndrome which is different than sleep apnea. Early on a lot of people that were being diagnosed with it were people that were morbidly obese or very overweight and so that's been kind of the perception.
What we're learning now is that, a lot of patients that I see in clinic are of normal weight that have sleep apnea and we think that a lot of it can be from jaw structure or things I was talking about earlier like having a narrow high arched palate or having kind of underdeveloped jaws which shrinks the size of the airway. And so patients that have a BMI or normal weight at 25 are still having sleep apnea particularly at an older age when they start losing that muscle tone.
What are some of the typical treatment options for sleep apnea?
So the most common and kind of first line treatment option is CPAP. CPAP means continuous positive airway pressure and this was first invented in 1981 by an Australian pulmonologist. What it is, is it's basically a continuous column of air that is delivered through the nose and/or mouth and it keeps the throat open.
I think about it like one of those inflatable things outside of a car wash that's kind of moving back and forth and there's this constant column of air that's being generated by a pad to hold that up. So that's kind of like what our airway is with CPAP, so you have this air coming in and if it shuts off the throat closes. But as long as that's on it kind of keeps the throat open and helps treat the obstructive sleep apnea.
Other treatment options include things like with something called a mandibular advancement device or an oral appliance. And so this is something a dentist can typically make and it's kind of like a retainer that you put in your mouth at nighttime and it holds the lower jaw forward. And that can be pretty effective for snoring, mild, and even moderate sleep apnea and is kind of another non-invasive intervention that people can use.
Are there lifestyle changes that people can make that can also help improve their sleep apnea?
One of the things that we found is that weight loss can significantly improve sleep apnea. And so some of the studies we have showed that even a 10% drop in your body weight so if you're 200 pounds and you drop 20 pounds, that that can reduce your sleep apnea severity from anywhere from 25% to 50%. Some patients' weight loss alone can completely resolve their sleep apnea or at least significantly improve their snoring.
Other lifestyle things: sleeping with your head elevated a little bit. So instead of sleeping totally flat the more kind of upright you are, the less gravity is kind of pulling on the throat and causing it to collapse. Sleeping on your side usually is better than sleeping on your back for the same kind of reasons that if you're laying on your back and gravity is kind of closing the throat from front to back usually sleep apnea is not as severe on the side for most people.
Other things such as decreasing the amount of alcohol you drink before bed. Alcohol significantly relaxes the muscles of the throat and so once you go to sleep everything is more likely to collapse. So you might remember if you had a couple too many drinks that your bed partner or maybe, you woke up with some bruised ribs because you were snoring a lot louder so it's the same thing with sleep apnea.
What are some of the newer alternative options for treating sleep apnea as well?
In my practice, there's a lot of different kind of CPAP alternative surgical interventions that you could do. For some patients it involves nasal surgery so if you have a really deviated septum or turbinates, or if you have big adenoids that are kind of like that tonsil tissue I described that are in the back of the nose, that improving that can certainly improve your nasal breathing and for a select group of patients that can be enough to help with snoring.
Other things, if you have big tonsils sometimes removing the tonsils and kind of repositioning the soft palate can help with sleep apnea. Taking out the lingual tonsils, which are actually tonsil tissue on the back of the tongue. Some patients have really big lingual tonsils and removing those can unblock the airway.
One of the newer surgeries is called INSPIRE and by new it's already eight years old now but inspire it was something that was created in 2014 or initially was FDA-approved in 2014. And what INSPIRE is, is it's called hypoglossal nerve stimulation. And so what that means is that it's essentially a pacemaker for the tongue.
It's a device that the pacemaker is put in on the right side of the chest with one incision here, and then another small incision just under the chin. In the incision here I find the nerve that controls the tongue and I put a little sensor on that and then there's a tiny wire that connects under the skin to the chest where this pacemaker sits.
Patients essentially have a little remote that sits next to your bed and every night they turn it on, put their remote down, and about 30 minutes after they fall asleep it turns on. And so instead of their tongue kind of falling backwards while they're sleeping, the device turns on and it moves the tongue forward every time you take a breath. And by improving the muscle tone in the back of the throat can help treat the sleep apnea.
Does that mean also that it's kind of shaping up the tongue as it's being trained to move forward? Could it potentially improve the tone of the tongue in the first place?
Exactly. That in particular can work really well for patients that have obstructive sleep apnea that we think is related to physiology. For those patients that are older in particular where it's potentially a muscle tone issue, that device is directly affecting the muscle tone and so that's why it can be really effective in the right patients.
Some other surgeries that I do are called skeletal surgery and so a lot of times those are selected for patients probably under the age of 60 on average. Some patients have a really narrow high arched palate and it causes trouble breathing through their nose because the nose is more narrow with the upper jaw being more narrow and we think there's also not enough room for the tongue. And so by doing a surgery actually, we can expand the upper jaw. I work with an orthodontist that puts a little expander on the roof of the mouth and expanding the upper jaw is a newer type of surgery that can significantly improve kind of nasal breathing and sleep apnea.
Then the last one is something called an MMA or a maxillomandibular advancement. That's the biggest surgery that we do at Rush for sleep apnea and it involves cutting the upper and the lower jaws and essentially moving everything forward and holding them in place with these little titanium plates.
By moving the jaws forward we're significantly increasing kind of the size of the box, the size of the room, and it puts a lot of tension on the tissues of the back of the throat and prevents it from collapsing. That's the biggest surgery and the most invasive but also the most effective so it can be about 90% effective at treating sleep apnea.
What's the recovery like from the INSPIRE surgery to some of the more advanced ones that you just mentioned?
The tonsil surgery as an adult is not the most pleasant surgery to recover, so I do it pretty selectively to take out patients' tonsils and kind of reposition their palate because it is two weeks of a pretty bad sore throat. But for the right patients, I say it's going to be two weeks of you not liking me very much and hopefully have a big improvement long term.
The INSPIRE surgery is actually much better tolerated it's about a two hour surgery, patients go home the same day. There's not a significant amount of pain because the incisions are on the outside so they're not actually in the throat where it's much more painful. And so after two or three days most patients are feeling much closer to their baseline but we just recommend they kind of take it easy for a couple of weeks after the surgeries they recover.
Whereas the skeletal surgeries, the MMA surgery is a couple months of a soft diet. Having moved the jaws forward and kind of allowing the bones to heal it's obviously a much longer recovery but again, it's kind of, we discussed three months of kind of recovery from this with hopefully many, many years of resolution of the sleep apnea so it's kind of putting a lot more investment up front for long term gain. Sure.
What have been some of the recent advances when it comes to sleep apnea research?&
I think there's a lot of improvements with CPAP so even within the last five to 10 years the masks have become much more comfortable, the machines have become quieter. And so for a lot of patients it's become much more tolerable that machines are smaller, they're easier to travel with.
In terms of the surgeries, sleep apnea surgery, the biggest part of my job is kind of picking the right patients. So selecting the right patients for the right types of procedures and so that's something that we're studying at RUSH right now.
Some of the things that we're doing here is we do something called a drug-induced sleep endoscopy. What that is, is it's essentially an airway exam or kind of looking at what parts of the throat are collapsing while a patient is asleep. So a patient comes to the operating room, we give them some propofol through their IV and basically get them sleepy enough to where they are snoring, they're kind of recreating these apneas or kind of pauses in their breathing. And then with a camera through the nose, I'm looking at the different levels of the back of the throat and seeing what part is exactly collapsing and what can I address surgically to help with that.
One of the things that we do differently at RUSH is that we actually use a CPAP mask that we hook up to the patient's nose. And we look through a camera through the CPAP mask and then while we're evaluating their airway, we turn the CPAP machine on and see what kind of pressure that patient needs to open their throat. We're one of just a couple of centers in the country that is using this type of technology and it really gives us a good example of visually what is collapsing, but then physiologically how collapsible is this person's airway.
Do they need this massive amount of pressure to keep it open? Or is there really not too much that is needed? And so with those things it helps us to have kind of better patient selection and picking the right surgeries for the right patients.
We've talked about snoring a couple times throughout this chat, but is snoring in and of itself bad for you?
There have been some studies that looked at snoring and how kind of vibration of the tissues of the throat can potentially cause cardiovascular issues. The thought is that, the carotid arteries run in each side of the neck which is right next to where the throat is where you're going to be snoring. And so there have been some studies to show that patients that are snoring could potentially have kind of more plaque or kind of thickening or injury of the carotids.
It's not studied enough to the point where everybody that has snoring needs to be treated but it's an interesting finding that we're trying to look more into kind of as a field to see is what's called primary snoring by itself does that put you at higher risk of eventually having a stroke and we don't have a good answer for that yet.
But a lot of times snoring is a sign of what's called flow limitation so the reason you're snoring is that the airway's narrowed and it causes more what's called turbulent or fast air flow and it causes the tissues of the throat to kind of vibrate. Sometimes that can be a sign of underlying sleep apnea, or at least something called upper airway resistance syndrome which is kind of an in between between snoring and sleep apnea.
It's a very long-winded answer to say we don't know but there are some things that are concerning for patients that have kind of long-standing snoring in terms of kind of cardiovascular issues.