By any measure, Donna Pahuski takes her health seriously. At 51, she exercises at least 45 minutes each day and makes good eating choices. So when she gained 20 pounds and her sleep became increasingly restless, at first she blamed it on menopause.
"But I thought it was interesting that after the hot flashes were gone, I was still such a poor sleeper," she remembers. "So when I saw my doctor two years ago, I mentioned possible sleep apnea. He suggested that the easiest way to check was for my husband to watch me sleep, but he falls asleep before I do. The other option was to come in for an overnight sleep test, but I wasn't eager to take the time, so I let it go."
This spring, Pahuski was diagnosed with cardiomyopathy, or weakening of the heart muscle. The left side of her heart was dangerously enlarged.
"The first thing the cardiologist said was, 'We need to test you for sleep apnea,'" recalls Pahuski. "He told me that sleep apnea would certainly accelerate my heart failure."
So Pahuski found herself descending the sunny steps into the quiet, underground clinic called Wisconsin Sleep, part of a larger program, the UW-Madison Center for Sleep Medicine and Sleep Research, to have her sleep apnea diagnosed. Each week about 60 patients spend the night there while their sleep problems are analyzed.
"The sleep test was lovely," says Pahuski. "It's a nice comfortable place, and the staff were kind and accommodating. I'm a very light sleeper. I knew it was going to be rough, and I only slept about three and a half hours, but it was enough to get the data and a diagnosis."
The center has 16 sleep rooms that serve the clinic's main purpose of treating clinical patients with sleep problems. In three additional sleep rooms, scientists probe topics like the effects of sleep deprivation on the brain and the effects of meditation on the sleeping brain, as well as conduct cutting-edge neurological research.
The center was highlighted in the May issue of National Geographic, and this September UW sleep researchers were featured in articles in The New York Times, Psychology Today Online and the academic journal Cognitive Neuroscience. Last year, the center's study of sleep apnea filled a slot on PBS's NewsHour.
Patrick J. Strollo, president of the American Academy of Sleep Medicine, calls the center one of the sleep field's leading institutions, responsible for significant research. "For example," he says, "studies of sleep apnea originating at the University of Wisconsin have helped shape the sleep medicine field."
The sleep center, which opened in 2007, replaced a sleep lab at University Hospital that was located too close to the hospital's emergency helicopter pad, whose noisy takeoffs and landings disrupted many tests. The new facility at 6001 Research Park Blvd. is tucked away on a quiet street off Odana Road, not far from West Towne Mall.
The center is underground, but the entrance has a two-story-high ceiling, and glass walls on the ground floor splash light down into the lobby. The sleep rooms are well protected from outside light and noise and pleasingly appointed with design details intended to put patients to sleep.
In fact, each sleep station resembles a comfortable hotel room, with a cozy, adjustable bed, a homey reading light on the bedside table and flat-screen satellite TV. Every room has a private bath where patients can shower and blow-dry their hair to get ready for work the next morning.
But the sleep lab is no hotel. It is both a research facility and a full-time clinic with 11 physicians and two nurse practitioners. Pediatricians, gerontologists, pulmonologists, neurologists and psychiatrists diagnose and treat nearly every possible sleep disorder here. Each room is also equipped with an infrared camera to monitor patients in the dark, a microphone that picks up any snoring, and electrophysiological recording equipment that monitors patients' brain waves, breathing, blood oxygen saturation, electrocardiogram and body movements.
This information is funneled to a control room with 16 stations, where each night-shift technician monitors one or two patients. Sitting up all night watching someone doze may sound like sleepy work, but sleep technician Becca Weise has no problem staying alert.
"A lot of the sleepers have complicated medical conditions. You are watching their breathing, heart rate and oxygen use. You don't have time to not pay attention," she says. "A lot of them are coming in with low oxygen levels, so you really have to be on your toes."
While the technicians remain vigilant, they must also help patients relax enough to drift off to dreamland in a strange room where they are wired to monitoring equipment and caught in the crosshairs of a camera.
"The camera can make them anxious," Weise admits. "We meet the patients before they go into the room. We hook all these wires up on them, which can take up to an hour. We want to make them feel comfortable, and we reassure them that we have had enough sleep to do our job."
In the morning, as sleepers wake up, get ready for work and even grab a continental breakfast on their way out, the monitoring stations are taken over by physicians who study the night's data for a rapid diagnosis.
Some of the most common sleep disorders are sleep apnea, insomnia and restless legs. More than a third of the people who come into a doctor's office have significant insomnia, according to Wisconsin Sleep director Ruth Benca.
"We need to educate patients about sleep and the simple behavioral treatments on how to take care of their sleep the same way we try to education patients about diet and exercise," says Benca. "We know that behavioral treatment for insomnia is at least as good as and maybe better than medications, and yet most primary care providers have never had any training in it."
Benca, whose own research ranges from sleep and behavioral problems of schoolchildren to sleeplessness in songbirds, is preparing a handbook for physicians on behavioral remedies.
Unfortunately, these don't work in every case. "The more medical or psychiatric problems you have," says Benca, "the more likely you are to have insomnia. Many commonly used medications can be very disruptive of sleep."
Though Wisconsin Sleep treats many sleep disorders, sleep apnea is its bread and butter. Sleep apnea is as common as adult diabetes and affects more than 18 million Americans, according to the National Sleep Foundation.
People with sleep apnea stop breathing during their sleep for at least 10 seconds, sometimes hundreds of times each night. Their breath is cut off because the muscles in the back of the throat fail to keep the airway open. A common cause is loss of muscle tone as part of the aging process that lets the opening sag. Even more commonly, the opening is being squeezed by accumulating layers of fat.
Unlike people with insomnia, who are usually acutely aware of their condition, many sleep apnea sufferers go undiagnosed.
Much of what is known about sleep apnea has been learned right here in Madison through the Wisconsin Sleep Cohort Study, ongoing since 1987 at the Institute for Clinical and Translational Research, located in the UW Hospital & Clinics.
For 23 years, Terry Young and her colleagues at the UW School of Medicine and Public Health have been following the sleep patterns and general condition of more than 1,300 area residents. The study is funded by the National Institutes of Health, and was recently approved for its fifth five-year cycle.
It began with more than 1,500 state employees, ranging from 30 to 60 years old, asked to participate in overnight sleep studies. These same people have been invited back every four years to see how their sleep and other health factors are changing over time.
"We study about four people a week in the Sleep Center, about 200 people a year," says Laurel Finn, a Population Health Sciences researcher at the UW. "There is nothing else in the world like what we are doing. Most studies are one-shot deals."
The study subjects were chosen from among public employees because they represented a relatively stable population. That made it easy to find them again for follow-up, a crucial element of any long-term study.
Most prior sleep research had been done with patients who were already being treated in sleep clinics. They were typically referred by their primary health-care provider and likely had underlying health problems. In contrast, a study based on a pool of state agency employees better represents a cross-section of the population.
The study's first blockbuster finding came in 1993, when Young and her group reported that sleep apnea affects 24% of men and 9% of women. Most health-care providers at the time didn't even think women could have sleep apnea.
More recently, sleep apnea has been tied to higher levels of stroke, depression, hypertension and cardiac problems. As their study subjects age, researchers are finding that people with untreated sleep apnea are three times as likely to die at a younger age from cardiovascular complications than those who don't have it.
Sleep apnea hits the heart hard. All night long sufferers get less oxygen, and each time the oxygen supply is cut off, the fight-or-flight nervous response triggers a spike in blood pressure and unhealthy hormonal shifts. People who are male, older and overweight are most at risk.
"The strongest risk factor for sleep apnea is obesity," says Paul Peppard, director of scientific operations for the Wisconsin Sleep Cohort Study. But it's not only the obese who need to be concerned: "Each small increase in body mass from the upper end of normal on up is associated with increasing risk of sleep apnea."
Here's why: Fat is deposited in the area of the upper airway right behind the nose and mouth. People who are overweight have more fat in that area, which makes the space for their windpipe smaller.
"Some people have sleep apnea and are not overweight," says Peppard. "They may have a small upper airway or an abnormality. For them losing weight won't help. But for the majority of people, losing weight should help. Dozens of studies have demonstrated this."
Unfortunately, weight loss can be a difficult and slow process, so the gold standard for treating sleep apnea involves sleeping with equipment called CPAP (continuous positive airway pressure). This involves wearing a nasal mask that gently blows air into the throat at a pressure high enough to keep the airway open.
Donna Pahuski is not part of the Sleep Cohort Study, but she could be its poster child. "I feel like a success story," she says. "If I hadn't had the sleep lab tests, I would only be treating my myopathy with medication, and I would be continuing to decline."
She knows what that decline would look like, having watched her mother contend with congestive heart failure starting at age 57. Her mother was never diagnosed with sleep apnea, but late in her life, an anesthesiologist prepping her for heart surgery noted signs of apnea in her throat. At that time sleep apnea and heart conditions had not yet been connected.
"She died at 72, and the last five years of her life were horrible," says Pahuski. "My mom's only sibling is now having the same trajectory. She's in her 70s and has the same myopathy. My mother's father dropped dead at 64. The doctors are pretty sure that I have inherited the condition."
Like many sleep apnea patients, Pahuski was prescribed a CPAP nasal mask, to put on every night at bedtime. "I was dreading it because I thought that kind of machine was for old, heavy men," she says. "I will not lie. The first couple of weeks were rough. But we keep a fan on high, and that masks the sound, and I've gotten used to it."
CPAP machines have become smaller, quieter and more sophisticated in recent years, says Dan Shea, respiratory therapist at Wisconsin Sleep, though their cost has held steady at about $2,500. Most insurance companies cover this equipment for people who experience more than five 10-second breathing stoppages an hour.
"The improvement is usually pretty immediate," he says, estimating that the center prescribes 30 to 35 CPAPs every week.
Sleep apnea is unusual in that it is one of the only snoozing realms that researchers have a handle on. When we don't get enough sleep, we pay for it. That price can include gaining weight, reduced attentiveness, higher risk of auto accidents, diabetes, heart problems, depression and substance abuse. But exactly how the body benefits from sleep is still a medical mystery.
Besides diagnosing and treating patients, the UW Center for Sleep Medicine and Sleep Research is a leader in the sleep field. In particular, researchers Giulio Tononi and Chiara Cirelli are breaking new ground in understanding the function of sleep - an important undertaking in our sleep-deprived culture.
"We spend a third of our life sleeping," says Cirelli. "When animals are asleep, they cannot easily respond to their environment, which can be very, very dangerous, so there must be powerful advantages to sleep."
Our brains, which account for a mere 2% of our body weight, hog 20% of the body's energy budget. Most of that energy goes into creating more synapses to take in new information all day long. Tononi and Cirelli believe that while the brain sleeps, it may be weeding out unnecessary synapses to keep our brains from clogging - like purging old files from a computer hard drive.
They are using electroencephalography (EEG), which records brain activity through electrodes attached to the head. Simple EEG is pretty common, but the UW sleep lab is the world's largest high-density EEG facility.
Thus the researchers are able to draw high-resolution pictures of the brain in action, and see which regions are firing while we sleep. This high-definition image is combined with information from vigilance tests to evaluate how alert the subject is.
"You look at a screen, and there is a light coming, and you have to push the button as fast as you see it coming," Cirelli explains. "This is a good indication of vigilance." (To take a vigilance test, visit their website.)
Recovery from sleep deprivation is a hot topic in sleep research. "Now there are a lot of studies," Cirelli says, "in which you restrict sleep to four hours for five days to mimic the length of a normal work week. Then you let them recover for two days. Unfortunately, it seems that when we do that just for a week or two, you start to see cognitive deficits."
Researchers are also looking at sleep restriction, where subjects chronically get a little less sleep than they need. Tests show that simply getting up at 5 a.m. instead of 7 a.m. can result in brain impairment.
"The most consistent finding," says Cirella, "is that people are unable to judge how impaired they are." They think they are okay, but a vigilance test may prove otherwise.
Benca agrees that sleep deprivation and driving don't mix. "We have done a great job of publicizing the risks of driving under the influence of alcohol," she says, "but I don't think people quite realize that driving when you are sleepy is at least as dangerous as driving when you are drunk. The idea that you can stay awake by turning on the air conditioning or opening the window or blaring the radio - none of those things really work."
The National Highway Traffic Safety Administration estimates that over 100,000 people are killed or injured each year in crashes due to a driver who has fallen asleep at the wheel or was inattentive due to severe drowsiness.
What constitutes normal sleep in a culture that is not only burning the candle at both ends, but microwaving it to a puddle of wax?
"Our sleep pattern in an industrial society, where we go to sleep when our heads hit the pillow, and the next thing we know, our alarm is going off to wake us up, is not a normal sleep pattern," says Benca. "If you need your alarm clock to wake up every morning, you are not getting enough sleep. That's a good rule of thumb."
As for Pahuski, since she started wearing a CPAP mask at the end of June, she is finally getting plenty of sleep. "Oh, my gosh," she says. "It's tremendously better. I don't need naps like I used to. What's more important, my heart is not getting stressed.
"And an added benefit - I'm not doing anything else different, but the weight is starting to come off. When you have sleep apnea, you have higher levels of the stress hormone cortisol. Everyone who has ever taken cortisone knows you gain weight for no reason when you are on it.
"Getting a diagnosis of heart disease reset my clock for me and reminded me what is important. Now I go to bed at 10 and wake up every morning at six with lots of energy. Who could ask for more than that?"
Do you have sleep apnea?
Sleep apnea is becoming so common that Wisconsin Sleep recently started allowing people who suspect they suffer from it to refer themselves directly to the center for testing.
And to help people self-diagnose, Wisconsin Sleep offers a short online test. People whose answers suggest a sleep apnea condition can send their results to the center, and a staff member will follow up with a screening by phone. Among the questions:
- Have you been told that you snore loudly on most nights?
- Do you stop breathing or struggle to breathe in your sleep?
- Are you often tired, fatigued or sleepy?
- Do you have acid reflux or high blood pressure?
- Are you overweight?
Three yes answers out of five could indicate sleep apnea.
The sleep apnea website of Wisconsin Sleep is www.wisconsinsleep.org/sleep-apnea.
How to sleep
Here are some tips on getting a good night's rest from the National Sleep Foundation.
- Avoid napping during the day.
- Exercise regularly, but no vigorous exercise close to bedtime.
- Go to bed and get up at about the same time each day, including weekends.
- Establish a relaxing bedtime routine.
- Sleep somewhere that is dark, quiet and comfortable.
- Don't eat close to bedtime.
- Lay off the caffeine, nicotine and alcohol a few hours before bed.