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"To sleep, perchance to dream; ay, there's the rub."
—"Hamlet," Act III, Scene I

On a highway in Nebraska a businessman, on a long commute home, drifts into oncoming traffic. In a manufacturing plant in Pennsylvania, a woman catches her hand in a machine. In a classroom in Nevada, a college student falls asleep in the middle of an exam. Scenarios like these play out every day across the country. The reality is, sleep is a precious commodity and Americans are not getting their share.

Included stories:

Oral Device May Be Answer to Sleep Disorder

What a Difference a Night Makes
Most adults need between eight and nine hours of sleep each night. Many Americans, however, aren't getting anywhere near that amount. Sleep rejuvenates the body: physically, emotionally and mentally. Sleep deprivation, on the other hand, causes fatigue, depression and irritability; increases the risk of injury; and may lead to serious health problems. The National Sleep Foundation says more than 60 percent of adults have sleep problems several nights a week. In addition, 40 percent experience daytime sleepiness that interferes with daily activities at least a few days each month, with more than 20 percent experiencing sleepiness a few days a week. That's a lot of tired people driving, working with dangerous equipment and making critical decisions.

"Americans in general are very sleepy," said Terry Stentz, assistant professor of construction management in the College of Engineering & Technology. Finding out why is critical, but it isn't easy. "Probably the least understood, or maybe the least communicated aspect of human behavior, is sleep. It's one of the final frontiers of the human brain." To complicate matters, many people also have sleep disorders or do shift work.

Stentz opened Somnos Sleep Disorders Center in 1989 in his garage with a $250 loan from his father. "We had no people, we had no test equipment and our first contract was with Harris Labs in Lincoln," he said. "Of course, being the typical entrepreneurial engineer, I said 'yes, yes, yes' to everything they asked. Then I went back to the garage and said, 'How are we going to do this?'" Stentz said laughing. He managed to do it by renting equipment and hiring temporary people. Then he got a second contract. Since then, Somnos has grown into a full-fledged laboratory with permanent employees, sleep rooms and its own state-of-the-art equipment. It also has an electrodiagnostics lab in the Beatrice and York hospitals and a freestanding lab on the VA campus in Grand Island.


Top: Dr. Stentz and Troy Stentz analyze sleep patterns from a sleep study at Somonos Sleep Lab.
Bottom: Steve Shea has been studying sleep disorders for more than 20 years. Here, he demonstrates a technique he uses in his research on Terry Stentz. The technique involves the insertion of electrodes into the genioglossus muscle under the tongue as a way to record muscle activity of the upper airway dilator and how it changes when people sleep. One of the leading causes of obstructive sleep apnea, Shea believes, is that the muscle relaxes and the tongue blocks the airway.
Today, the lab performs sleep studies on hundreds of patients each year who are suffering from sleep disorders, of which there are more than 200 including obstructive sleep apnea. Obstructive sleep apnea, a serious sleep disorder that can have far-reaching repercussions, occurs when the upper airway at the back of the throat is blocked as the tongue and other tissues relax and collapse, closing or blocking the airway. Those suffering from this disorder stop breathing during sleep—sometimes for a few seconds, sometimes for several minutes—then gasp or choke for air. In severe cases, this happens hundreds of times a night. Each time, the person wakes, which does not allow the body to get the sleep it needs. "Sometimes we have patients who have obstructive apnea so severe, they can't fall asleep in a supine position. We have to instrument them and put them in a recliner so we can get data on them," said Tim Stentz, chief sleep technologist at Somnos.

Individuals come to the lab to be observed and measured while sleeping. They are hooked up to electrodes that monitor breathing, R.E.M., brain and heart activity, as well as thoracic and abdominal efforts. The results of the polysomnogram are sent to a sleep medicine physician for interpretation. If sleep disorders are discovered, the individual is referred to their family doctor.

After working for several years in the private sector, Stentz (MSIE '96; PhD '97), a retired naval reserve intelligence officer with 27 years in the military, returned to college in 1990 during what he called a mid-life crisis. "Instead of buying a Porsche, I went back to college—and into the poor house in a hurry," he said laughing. He began working as a research associate with Mike Riley, chair of industrial and management systems engineering. Together, with Ram Bishu, another professor in IMSE, they studied job performance in over-the-road truck drivers and over-the-road sleeping environments for Mid-America Transportation Center. The results were not surprising. They found that drivers suffered fatigue, muscle pain and other stresses—much of it because they drove at odd times of the day or night and slept mostly in truck cabs. The two biggest problems drivers encountered were fumes (drivers keep their trucks running all night for refrigeration and comfort reasons) and noise and disturbance. Those factors contributed to injury, illness, low morale and physical and mental problems. The problems were compounded, they discovered, when drivers had sleep disorders and were operating counter to their circadian rhythms or sleep/wake cycles.

"Humans operate on a 24-hour sleep/wake cycle that is brain driven and a fundamental physiological requirement to function well," Stentz said. Too frequently that cycle is in conflict with work and activity patterns and the rapidly changing level of technology in our society. "We're constantly re-engineering our natural and built environment, not taking into account that we are biological creatures. As engineers we need to account for the human element in all our designs. Everything engineers do affects humans—we need to make sure we include the human factor in our designs and applications."

Two years ago, Stentz expanded his research with "Industrial Worker Sleep Behavior and Safety: A Prospective Study," a funded research project on which he is co-principal investigator with Steven Shea, associate director of the sleep disorders programs and associate professor of medicine at Harvard Medical School. The project focuses primarily on industrial shift workers, people who work outside the normal 8 a.m. to 5 p.m. shift and are most likely to suffer from disruptions in the sleep/wake cycle.

"The importance of sleep is underestimated by the general public, especially in this 24-hour society," said Shea, who has been researching sleep disorders for more than 20 years. "Slowly we're finding out how important it is to respect sleep and, secondly, how important it is to help the public respect it more." In addition to the problems cited earlier, sleep deprivation has caused major catastrophes, Shea said. Examples include the Exxon Valdez, which dumped 11 million gallons of oil into Alaska's Prince William Sound in March 1989, and the explosion that killed 7 astronauts aboard the Challenger Space Shuttle in 1986. "The Exxon Valdez accident can be related to sleep deprivation—the third mate had slept only six hours in 48 hours," Shea said. And the decision to launch the Challenger in freezing weather was made after people had been working 20-hour shifts. "The decision-making ability is affected by sleep, and, very importantly, when you do your work," he said.

How to Sleep Well

These guidelines can be helpful in alleviating all types of sleep disorders and will help most people sleep well.

  • Get out of bed about the same time every day
  • Go to bed only when sleepy
  • Establish relaxing pre-sleep rituals: warm bath, light bedtime snack, 10 minutes of reading
  • Exercise regularly—confine rigorous workouts to early hours (at least 6 hours before bed), and mild workouts, like stretching or walking at least 4 hours before bedtime
  • Keep a regular schedule to keep the biological clock running smoothly
  • Avoid caffeine for 6 hours before bedtime and alcohol, especially when tired
  • Avoid smoking close to bedtime
  • Avoid sleeping pills or use cautiously; do not use alcohol while taking sleeping pills

Common Associative Factors in Patients with Sleep Apnea


Male
  • Over 40
  • Overweight
  • Sedentary
  • Big neck
  • Family history of apnea in other males within the family

Female
  • Pre-menopausal: The same associative factors found in men are not apparent
  • Postmenopausal: Associative factors and prevalence of apneas begins to look very similar to those in males
In many cases in both males and females, significant weight loss, regular aerobic activity and strength training can reduce the severity of apnea.
In America there is a growing number of shift workers, creating unique problems in work environments. According to Stentz, about 20 percent of the adult population in America is biologically well suited to shift work—those people are called "owls." About 20 percent more are morning people—or "larks." "Larks have an extremely difficult time adapting to shift work. The other 60 percent, with the right work adjustments and the right management systems, can be trained and will adjust to shift work." That means only 20 percent of the population is naturally suited for shift work—"That's a sizeable problem for industrial management," Stentz said.

Stentz met Shea while working toward his master of public health in occupational and environmental health at Harvard School of Public Health. Shea, his professor at the time, was so impressed with the paper, he told Stentz he thought Harvard and Liberty Mutual Insurance, a co-sponsor in the study, would fund it. They received the first grant in 2001 and another this year. The two formulated a survey for nearly 7,000 manufacturing industry workers in 11 Nebraska plants: food processing, farm equipment, hand tools, electronics and office fixtures. They chose these fields because they are contained work environments that have three shifts. Also, the employees operate heavy machinery and semi-automated equipment, drive a vehicle or work with sharp objects. Workers volunteered for the study with about 3,000 participating—a 43 percent response rate. The majority of those responding were production workers, with some administrators responding as well. Although it's a voluntary convenience sample, the large sample gives the study a measure of legitimacy, Stentz said. The survey contained demographic questions; the Epworth sleepiness scale, which focuses on sleep behavior, and 21 other questions about sleep disorders and sleep behaviors on a frequency response scale.

The primary hypothesis of the study is that "OSHA-recordable work-related injuries are greater in sleepy workers with self-reported symptoms of sleep disorders and that the risk of injury in shift workers is higher than in day workers," Stentz said. "Once you establish relative risk and show a strong association, then our job as health scientists and industrial engineers is to design worker health and industrial management systems to reduce that risk," Stentz said. Because it's a prospective study, it will take several years to complete. "We're waiting for things to happen to see if there is any correlation between accidents in the work place and our estimates of sleep disorders on the questionnaire," said Shea. "Such studies are difficult, expensive, time-consuming and tedious," added Stentz. "But done correctly, they can be extremely powerful and informative."

Preliminary results show that approximately 40 percent of those responding to the survey had an Epworth score of 10 or higher, meaning they are "too sleepy," said Stentz. "This does not necessarily suggest sleep disorders, only that these people are not getting enough sleep. That could be because of fragmented sleep, or because they are not sleeping enough hours." But the study does suggest that 10-20 percent of respondents suffer from sleep apnea, up to 14 percent suffer from restless legs syndrome and 3-10 percent reported symptoms of narcolepsy, a surprising result. "If this is true, it's extremely high and a real cause for concern."

In the future, Stentz believes this research will be applied to workers in a number of occupations that involve shift work including manufacturing, transportation and construction, which is beginning to adopt shift work as a way to push the schedule. For example, the Boston "Big Dig" tunnel project runs three shifts a day, seven days a week and employs about 5,000 workers, he said. In the meantime, Stentz and Shea are focusing on the next phase of the project: a larger national study that will recruit general industry workers nationwide, validation of the results through sleep studies, a pilot observation study and designing a management system. The researchers are hoping for funding through the National Institute for Occupational Safety and Health or the National Institutes of Health.

If they are successful, Stentz believes they will be able to go a long way in helping management and workers find solutions to some of the sleep problems plaguing so many American workers. "Well-rested workers are in fact better workers and safer workers—with higher levels of productivity and fewer accidents and mistakes—in the workplace and on the road," Stentz said.

For more information on sleep disorders go to the National Sleep Foundation Web site at http://www.sleepfoundation.org and the American Academy of Sleep Medicine at http://www.aasmnet.org

Oral Device May be One Answer to Sleep Disorder

For nearly two decades, Ron Attanasio of the University of Nebraska College of Dentistry in Lincoln has been helping people overcome snoring problems by designing oral devices—or anti-snoring splints—for them. But until his wife pulled him aside, the dental college professor didn't realize how much significance the maxim "physician, heal thyself" held.



Top: Dr. Ron Attanasio poses with the acoustic pharyngometer, a device that could potentially identify if there is an anatomical area of the airway that could be contributing to sleep disorders.
Middle: Oral appliances change the position of the jaw, can reduce or eliminate snoring, and help reduce sleep apnea.
Bottom: This diagram demonstrates how the acoustic pharyngometry works.

"She said, 'You know Ron, you've been making all these devices for your patients, do you think you could make one for yourself?'" Attanasio, who is also the director of the College of Dentistry's TMD Orofacial Pain Clinic, said laughing.

And so he did. Although the device stopped his snoring, he continued to have problems during sleep: his wife frequently witnessed him gasping for air or not breathing at all. She began to time the episodes, some of which lasted for up to 30 seconds. He didn't think it was a serious problem—until the day he ended up in the hospital emergency room suffering from what was believed to be a heart attack. While conducting a catheterization on Attanasio prior to open-heart surgery, the doctor realized Attanasio had no obstruction in the heart. His doctor suggested a sleep study, which determined he was suffering from obstructive sleep apnea, a sleep disorder that can lead to serious health problems.

"I had 400 apneic episodes in a seven-hour period," he said. "That's an awful lot." In fact, the sleep apnea was forcing his heart to work harder, which created heart attack-like symptoms. He began using a CPAP machine, a device that continuously pushes air into the airway, forcing it stay open. It changed his life.

"Sleep apnea occurs for several reasons," said Terry Stentz, assistant professor of construction management and director of Somnos Sleep Laboratories in Lincoln. The most common reason is upper airway obstruction, which occurs mostly when people sleep on their backs. The second is central apnea in which there is no obstruction; the brain simply doesn't send a message to breathe. The third is both obstruction and central together.

"The interesting thing is that when we treat people for obstructive, it usually clears up the central apnea as well," Stentz said.

After his experiences, Attanasio became interested in obstructive sleep apnea and how a specially designed oral appliance can reduce or eliminate snoring, as well as help reduce sleep apnea. During sleep, jaw position changes, as does muscle tone in the throat and tongue, causing the tongue to relax and block the throat. "When people go to sleep, we just don't know what happens."

To develop the oral devices, Attanasio began using an acoustic pharyngometer (Eccovision), which was loaned on consignment for his research from Hood Labs Inc., a medical equipment company in Massacusetts. The pharyngometer works with sound waves that are sent through the mouth to the back of the throat. As the wave reflects back, sensors in the pharyngometer are analyzed and the instrument diagrams the dimension and geometry of the oral cavity all the way to the back of the throat where airway obstruction from the tongue and soft palate can occur.

The device could potentially identify if there is an anatomical area of the airway that could be contributing to sleep disorders. "With this technology we get a baseline of where patients are in their current state of breathing, then make a bite record for an oral appliance that is representative of the optimum airway dimensions as determined by the pharyngometry instrumentation," Attanasio said.

The bite record determines the optimum position for the design of an oral appliance, which changes the size and geometry of the oral cavity by moving the jaw forward. When Attanasio and his team began doing research on the pharyngometer, he realized he needed to work with a sleep lab to test the effectiveness of the pharyngometer and oral splints.

His associate, Dr. Eric Fung, a pharmacology professor with the dental college, suggested Somnos Sleep lab, where he had had a sleep study done. Attanasio, Fung and Stentz have been working together for about a year and half. Fung will be reviewing medications patients will be taking to determine how they may affect sleep. Based on preliminary studies they intend to seek additional funding for a study involving more patients.

Stentz, who has been researching transient risk factors associated with shift work and sleep disorders, was excited about working with the dental college. Several subjects involved in his research will be fitted with Attanasio's oral splints then tested in the sleep lab.

Up to 100 volunteers involved in the project will spend three nights in the sleep lab: one night with no apparatus to assist breathing, one night using the CPAP and the final night using an oral splint. The results will be compared to see which device works best for the individual. The results also will generate other technical and research questions that will be dealt with in future projects. It is a long-term research endeavor.

"Between the engineering college, the dental college and the sleep lab, we can create a better dental appliance design for a more effective treatment of minimum to mild obstructive sleep apnea," Stentz said.

Constance Walter

What a Difference a Night Makes

It was an offhand remark made while interviewing Terry Stentz for this story that sent me to the sleep lab. "My husband says I stop breathing sometimes while I'm sleeping," I said. "You could have sleep apnea," he said. "You should come to the sleep lab for a study." Then he suggested we make it part of the story—give people a firsthand account of the experience. It would also have an added health benefit: I would know once and for all if I had sleep apnea, a serious health threat. Before doing the sleep study, I did the Epworth Sleepiness Scale, a questionnaire that assesses sleepiness in common life situations. This is a story in pictures about my night in the lab.

photography by Tom Slocum
1. Before being hooked up to electrodes, technologist Tim Stentz took my vital signs. So far, so good.

2. Stentz asks me about my day—did I feel tired? Fatigued? Did I feel the need to take a nap? Yes. Yes. Yes.

3. Stentz prepares the skin and electrodes for application. The surface of the skin must be gently abraded to get a good connection.

4. Electrodes are applied to my face, head, legs and chest so technicians can monitor REM, brain and heart and activity, as well as leg movement.

5. Respiratory belts measure thoracic and abdominal efforts.

6. Just where do all those electrode wires go? Into the "head box," which is plugged into a computer system that allows technicians to monitor activity, breathing and oxygen levels.

7. Settling in for the night. The sleep lab wants people undergoing a polysomnogram to keep as close as possible to their nightly routines. I always read for at least 15 minutes before turning out the lights. That night it was "Lord of the Rings: The Two Towers." I'm a big fan.

8. I didn't think it would be possible to fall asleep with so many wires connected to my body. But I fell asleep in record time.

9. After the study is scored by a technologist, it is sent to Dr. John Trapp, a pulmonologist and board-certified sleep medicine physician, for interpretation, diagnosis and treatment recommendation. The diagnosis: mild to moderate sleep apnea. During the night, I had 61 arousals: 39 were breathing related, one was a leg jerk and 21 were spontaneous, which are common to normal sleep. I had 19 obstructive apneas, including one that lasted 63 seconds in REM and one that lasted 58 seconds in non-REM. Try holding your breath that long. It's impossible. Many people who suffer from obstructive sleep apnea wake up hundreds of times during the night, causing irritability, lower productivity and fatique, which can be dangerous in certain jobs. It also can increase blood pressure, heart rate and desaturate blood oxygen level. In fact, at one point my blood oxygen level dropped to 80 percent.

10. What a difference a CPAP makes! I returned to Somnos Sleep Lab a second time to try the CPAP (continuous positive airway pressure), a device that continuously pushes air into the upper airway to keep it open. Despite making me look like an alien, the CPAP machine gave me the first truly restful night I'd had in years. I awoke refreshed and rested. My family doctor, who has also been monitoring my process through the sleep lab, recommended I use the CPAP on a regular basis.

Constance Walter