Joey Wahler (Host): They can help diagnose sleep disorders, but many people don't know much about them. So we're discussing sleep studies. Our guest, Dr. Cameron Barber, a Sleep Medicine Physician with WakeMed Sleep Medicine. This is WakeMed Voices, brought to you by WakeMed Health and Hospitals in Raleigh, North Carolina.

Thanks for listening. I'm Joey Wahler. Hi there, Dr. Barber. Thanks for joining us.

Cameron Barber, DO: Hi Joey, great to be here.

Host: Great to have you aboard. So first, what exactly is the purpose of a sleep study?

Cameron Barber, DO: A sleep study is designed to observe and analyze your sleep overnight and detect almost all sleep disorders.

Host: And so when does someone know if they need one? When should they see a sleep medicine specialist like you and yours?

Cameron Barber, DO: So any physician can order a sleep study. A Sleep Medicine Specialist is most certainly an appropriate avenue. Some primary cares feel comfortable ordering them on their own. Others feel comfortable referring in. It depends on the network. Here at WakeMed, we have both happening. I see people that have had their sleep studies done or people that haven't.

But whenever there's any unrefreshing sleep or concern for sleep apnea, loud, disruptive snoring, or overall not feeling like your sleep was 100%, that's the time that it's worth discussing whether or not a sleep study is right for you.

Host: Gotcha. And so what types of conditions can a sleep study diagnose?

Cameron Barber, DO: So a sleep study is geared to diagnose things like sleep related breathing disorders. This includes obstructive sleep apnea, which is where there's a collapse in your upper airway, stopping breathing, often resulting in loud snoring and unrefreshing sleep. Also things like central sleep apnea, which for lack of a better way to describe it is when your body forgets to breathe.

And we can diagnose abnormal movements and parasomnias overnight, such as REM sleep behavior disorder. There are a couple other subtypes of sleep studies that are special studies. One is a CPAP titration study, which is where patients that already have a diagnosis of sleep apnea are on a treatment, and we're trying to optimize the treatment, make sure that they're on the best pressure to help treat their apnea, or find out if there's other disorders going on.

And then there's a daytime study that can help diagnose sleepiness disorders or disorders of hypersomnia. This includes narcolepsy and idiopathic hypersomnia, and these actually are combined with a nighttime sleep test, and they show you that you can fall asleep fast and quickly enough during the daytime, which ultimately diagnoses the conditions like narcolepsy.

Host: Gotcha. So what types of things does a sleep study measure exactly? What are you looking at?

Cameron Barber, DO: So starting at the top of the body, we have wires connected to the head. Those are measuring EEG. What we're looking at there is whether you fall asleep or not. What stage of sleep you're in. We have the leads around the eyes to detect rapid eye movement sleep, which is our dream sleep or REM sleep.

We have leads on the chin, the arms, the legs, and we're detecting movements. When we're in dream sleep, our body is supposed to be paralyzed. So one way we can ensure that your in dream sleep is making sure that you don't have muscle tone, but one of the diseases of sleep medicine is REM sleep without atonia, or REM sleep behavior disorder, and so if you're in rapid eye movement sleep and you're still moving your legs and arms, that's one of the diseases that we can diagnose with the sleep study.

We have a nasal cannula that goes underneath your nose to measure the airflow in and out of your nose, and then something called the thermistor that goes around your mouth to measure airflow in and out of your mouth. Those two devices combined with a chest belt and a belly belt, looking for how you're breathing, in addition to a pulse ox, which looks at your heart rate and your oxygen level, help us diagnose things like sleep related breathing disorders such as obstructive sleep apnea.

If people are found to have stopped breaths, called an apnea, or a weak breath called a hypopnea that causes their oxygen to drop overnight and or wakes them up more than five times an hour, that's considered diagnostic for obstructive sleep apnea.

Host: And so that's certainly a lot of stuff that you can check and monitor. Where does all this happen?

Cameron Barber, DO: Yes, so an in lab diagnostic polysomnography or a sleep study typically occurs inside a sleep lab. WakeMed has a beautiful nine bed sleep lab. I like to describe it. It's similar to a medium to nice quality hotel. You have your own private bedroom, your own private queen size bed, a TV in the room, your own private bathroom, and they get you set up at night and you go to sleep at your own time.

You sleep overnight and you're monitored to make sure all the equipment works well and there's no equipment failures and that you're safe. And then the data comes to me and I score it and write a report and find a diagnosis.

There's another type of sleep study called a home sleep study. This is designed specifically to just look for obstructive sleep apnea. Most people are going to be more familiar with this study. There's a couple different types of them. One type is still looking at airflow. So you have generally a chest belt that goes for your breathing. It also monitors your body position and your snoring.

Then you have finger probe that looks at your heart rate and your oxygen and a nasal cannula that looks at your airflow overnight. This is a good test. It's a cheaper test, it's an easier test for most people to rule in obstructive sleep apnea, or to be able to say yes, you do have obstructive sleep apnea.

Unfortunately, it doesn't have a good negative predictive value. That means it's not a good test to say you don't have sleep apnea. It does have about 10 percent of the time false negatives where people actually have sleep apnea, and we need to confirm that they do you have it in the sleep lab rather than at home.

Host: So you've described the beautiful conditions, as you put it, you've described the very elaborate equipment as well, in terms of length of the study, how long does this usually take? And do you need to do it more than once?

Cameron Barber, DO: Typically, patients get set up in our sleep lab sometime around 8:30 to 9:30 at night, and then they're allowed to fall asleep. Ideally, I want a sleep study done, not an awake study, so I hope that you can fall asleep earlier, but it does happen where people stay awake for several hours.

As long as we get somewhere between four to six hours of sleep, we can be fairly confident this was a good sleep study. The technicians typically tend to wake patients up sometime in the morning between five o'clock and seven o'clock depending on how that sleep lab is ran, and they get them unhooked from the equipment, and that's how a sleep study goes.

A home sleep study is often set up, they explain the device and provide the device to you sometime during the day, then you go home. You can sleep at your own time, after you set yourself up before bedtime, whether that's going to bed at, eight o'clock at night or four o'clock in the morning, you sleep as long as you want, turn the device off, take it off and return it at your convenience the next day.

This is a good test, especially for people that have shift work or work third shift, or where they basically don't sleep at night for any number of reasons.

Host: So you can actually send them home with that device after the study, if it's found that that's what they need?

Cameron Barber, DO: Before the study, that would be the study they're being sent home with, yes.

Host: And so what about any other results that you wind up with, are those available right away?

Cameron Barber, DO: The results can take up to a couple weeks to interpret. There's a process where the data has to be looked at and scored every 30 seconds. You have to tell them whether they're asleep or awake and identify count all the bad breaths, all the times they woke up, any time they kicked their legs, and then review the whole data and write a report and find any diagnosis.

Unfortunately, sometimes people do have to have repeat sleep studies for many reasons. A home study that was negative, may need to get repeated in the lab if there was a technical failure or ultimately if the patient wasn't able to sleep at least two hours in the sleep lab, it may need to be repeated that way as well.

But for the most time, one night is good enough to diagnose common disorders such as obstructive sleep apnea.

Host: Excellent. Couple of other things. Any common misconceptions about sleep studies that you can clear up for us?

Cameron Barber, DO: I think a lot of people are worried about a sleep study being uncomfortable. We understand that there's a lot that goes on with sleep and a lot of people don't like to sleep in new environments. So first, knowing that there is an option to do a home sleep study if you need that or request that.

Otherwise, when you do come into the sleep lab, we do make it our best effort to make you as comfortable and relaxed as possible. Again, we want to watch you sleep. We don't want to see you awake all night. So that's why we do provide these amenities. You're welcome to bring things in from home. You're welcome to bring your own blankets, your own pillows, your own stuffed animal, if you'd like.

And there are times when we need to bring in something like extra family members, chaperones. In pediatric sleep studies, an adult or parent is required to be there at night. But sometimes in our older population, they need a family member to be there just to be calm and prevent agitation or confusion. And we're welcome to accommodate that as well.

Host: And so in summary here, Doc, you touched on earlier the fact that many people procrastinate when it comes to addressing sleep disorders. Perhaps they don't necessarily think they have a problem. Maybe they just think it's stress or too much caffeine or what have you. So what would you say in summary here to our listeners that may be putting off getting their sleep issues checked out?

Cameron Barber, DO: Absolutely. There are estimated to be 80 million people in the United States with a sleep breathing disorder such as obstructive sleep apnea that are undiagnosed. People who have loud snoring, who have unrefreshing sleep, or they wake up feeling not restored, should definitely get checked out for sleep apnea.

People with high blood pressure, overweight, or an irregular heart rate called atrial fibrillation also should their doctors about whether or not they should get a sleep study to rule out obstructive sleep apnea. Untreated obstructive sleep apnea can lead to things like an increased risk of heart attack, stroke, and that atrial fibrillation I mentioned.

So if we can treat your apnea, we can prevent diseases and disorders that occur that can have significant morbidity and mortality in the future as well as making you feel better, more awake, alert, and productive in the meantime.

Host: So nip it in the bud, right?

Cameron Barber, DO: Yes, sir.

Host: And to learn more about WakeMed sleep services, please visit wakemed.org. Again, that's wakemed.org. Well folks, we trust you're now more familiar with sleep studies. Dr. Cameron Barber, valuable information indeed. Thanks so much again.

Cameron Barber, DO: Thank you for having me here.

Host: Absolutely. And if you found this podcast helpful, folks, please do share it on your social media. I'm Joey Wahler. And thanks again for listening to WakeMed Voices, brought to you by WakeMed Health and Hospitals in Raleigh, North Carolina.