by Margaret Wahl

Scott Porterfield of Hilliard, Ohio, says he's occasionally had to spend the night in his wheelchair because he's found it impossible to get comfortable in bed.

Porterfield, who's 6 feet 3 inches tall and weighs 200 pounds, has Becker muscular dystrophy and enough muscle weakness to keep him nearly immobilized without mechanical aids. His shoulders are uneven, making the left one higher than the right when he tries to lie flat in bed. It's the left shoulder that gives him the most trouble.

"The numbness starts in the shoulder and eventually the whole arm will go numb. It becomes very uncomfortable and at times extremely painful," says the 30-year-old Porterfield.

Unfortunately, such problems aren't uncommon in neuromuscular disease, says neurologist John Kissel, who co-directs the MDA clinic at Ohio State University Medical Center in Columbus. Kissel says a certain amount of musculoskeletal aching and general discomfort goes along with weakness and immobilized joints. Then there's simply the inability to spontaneously move to change position.

Normally, Kissel says, people change position often when they're in bed or give a good stretch to their muscles. If you can't do that, discomfort or even pain can result. "You can start off in a position that's relatively comfortable, but then after a while it's not, and you can't change it."

Kissel has recommended various kinds of pain relief for his patients, including anti-inflammatory medications; TENS (transcutaneous electrical nerve stimulation) units; stretching exercises before bed (these can be done passively, with someone else moving the limbs), preferably after instruction by a physical therapist; and changes of mattresses, pillows and other bed items.

All can be effective to an extent, and sometimes patience and experimentation are needed. "Probably the most common misconception is assuming that changing a mattress will work," Kissel says. "Some people will say, 'I've heard waterbeds can work,' and then they go buy a waterbed and find that it doesn't work for them. Some waterbeds are hard, and some are real soft. Try the bed first."

Kissel adds, "In patients where the problem hangs on, you have to be sure it isn't a psychiatric problem or sleep apnea [cessation of breathing during sleep] or something else." He remembers with regret a young man who continued to complain of insomnia and back pain and was eventually found to have a fractured vertebra.

What Is Sleep?

After thousands of years of philosophical observations and decades of scientific studies, we still know relatively little about what sleep really is - except that it happens in the brain and that it's absolutely necessary for physical and mental well-being.

The onset of sleep may have something to do with a brain chemical known as GABA (gamma-aminobutyric acid), which quiets the activity of the nerve cells it reaches. Most sleep medications are thought to act by enhancing or imitating GABA's actions. Still, there are so many brain phenomena associated with sleep that it's hard for experts to say which ones actually cause sleep and which ones are just along for the ride.

We know that sleep seems to exist in at least two forms: slow-wave sleep and REM, or rapid eye movement, sleep. During slow-wave sleep, which ranges from light to deep, brain waves are generally slower (farther apart) than they are during wakefulness. During REM sleep, when dreams occur, brain waves more closely resemble wakefulness, and the eyes dart back and forth as if watching a movie, all while the sleeper appears in other ways to be in a deep sleep.

The average person cycles through slow-wave sleep and REM sleep four or five times a night, with slow-wave sleep making up about 75 percent and REM sleep about 25 percent of the night, at least in young adults. The overall pattern of sleep is known as sleep architecture, and it can be altered by pain, stress, disease, medications, alcohol, caffeine, aging and other factors. Some sleep remedies change sleep architecture, resulting in a sleep that's not as refreshing as natural sleep.

During sleep, respiratory movements are less effective, and the upper airway can collapse as certain muscles in the throat area relax.

The Breathing Connection

Of all the problems that interfere with sleep in someone with a neuromuscular disease, breathing abnormalities are among the most serious. Unfortunately, they're often overlooked unless careful testing, such as a sleep study, is done. (See Quest's two-part series on respiratory care.)

In most neuromuscular disorders, particularly the muscular dystrophies, myasthenias, motor neuron disorders and metabolic muscle diseases, the muscles that control respiration (mostly the diaphragm and those between the ribs) can gradually weaken, interfering with ventilation, the act of taking in air and letting it out.

During the night, it's normal to have changes in ventilation. Complex neurologic factors, as well as position and gravity, change nighttime breathing, especially during deep sleep. In the average person, even though breathing efforts are less effective during sleep, they're still good enough. But if respiratory muscles are weak, as they often are in neuromuscular disease, these efforts can easily fall below a safe threshold, leading to low oxygen and high carbon dioxide levels during the night.

It takes quite a bit of respiratory interference to cause shortness of breath. Instead, you're likely to feel groggy during the day, or to doze frequently; appear dull, apathetic or depressed; or often wake with a headache in the morning. You may even be unaware that you're not sleeping well during the night and that your nighttime oxygen and carbon dioxide levels are off.

Some people with neuromuscular disorders also have weakness of the upper airway muscles, so that the upper airway can periodically collapse and block air flow during sleep. A bed partner or caregiver may notice snoring if the airway is partially blocked. Periodic cessations of breathing lasting several seconds, sometimes as many as 20 to 60 times an hour, can occur if it's completely blocked. This latter condition is known as obstructive sleep apnea and can be very serious if left untreated.

Myotonic muscular dystrophy (MMD) seems to be a special case, affecting not only the muscles involved in breathing, but also cells in the brain that control how we breathe. During sleep, many people with this disorder can fail to breathe normally because of this brain factor - a condition known as central sleep apnea (because of the involvement of the central nervous system).

The usual treatment for sleep apnea, whether it's obstructive or central, and for ineffective nighttime ventilation (sleep-related hypoventilation, or hypopnea), is noninvasive positive pressure ventilation. This means using a small ventilator that pumps air into the lungs via a mask that fits over the nose or nose and mouth to assist your breathing.

The type of NIPPV usually used in neuromuscular disease is bilevel positive airway pressure, or BiPAP. (Although often used generically, BiPAP is actually a brand name belonging to Respironics Inc.)

Bilevel pressure, as contrasted with continuous pressure (CPAP), allows a lower pressure to exhale against and delivers a higher pressure on inhalation. CPAP, often used for sleep apnea in people without neuromuscular disease, delivers one level of pressure continuously, making it hard for the person with weak respiratory muscles to exhale.

For some patients, a set volume, rather than a set pressure, of air works better. This requires a different type of device.

Often, the use of nighttime NIPPV markedly improves daytime functioning as well as the quality of sleep.

A screening test for sleep apnea or hypoventilation that affects oxygen levels can be performed using an oxygen sensor (oximeter), a small, surface electrode attached to a finger or earlobe during the night to measure oxygen levels in the blood. A more comprehensive look at sleep-related breathing patterns is achieved with a full sleep study, in which the patient is monitored overnight with electrodes measuring respiratory efforts, oxygen levels and stages of sleep, among other functions. Sometimes, sleep apnea or hypoventilation interfere so much with sleep that the person never reaches deep sleep at all, something only a sleep study can detect.

Taming Stress

Leaving your problems at the bedroom door is a good idea for anyone, although it's easier said than done, especially for those with serious illnesses. But, as much as possible, it's important to recognize and deal with stress to get a good night's sleep.

Tom Roth, 43, of Gibsonia, Pa., recently learned he has amyotrophic lateral sclerosis, a disorder that usually leads to complete paralysis and death within a few years. With four young children to support, Roth has plenty to worry about.

Muscle twitches, a common feature of ALS, would be hard enough to take during the night, says Roth, but the psychological component of these twitches makes them much harder to bear.

"The twitching is just a constant reminder of the disease," he says. "It's as if someone's poking me in the back and saying, 'Remember now, you've got ALS.'" Once he does drop off to sleep, twitches and all, he says, "That's when the cramps kick in. They wake me up throughout the night."

Stretching exercises before bed, a heating pad, massages by his wife and, especially, the drug tizanidine (Zanaflex) have helped reduce the twitching and cramping, Roth says. He's had to work harder to tame his worries.

He says he's gotten a surprising amount of help from reading Who Moved My Cheese? by Spencer Johnson (Putnam Publishing Group, 1998), about coping with change and revising goals. The short book chronicles the adventures of four characters (two mice and two humanoids) whose cheese supply has disappeared.

"Basically, all it says is that change is inevitable, so you might as well plan and adapt your situation, be ready for when it does happen. Don't be oblivious to it so that when it happens you don't know what to do," Roth says.

For Roth, adapting to his situation has meant adjusting his work schedule and duties, spending more time on the computer and less in his manufacturing company's warehouse, and shortening his hours. He recently moved his office to a more accessible location in the building.

"The simple thing is that my legs are going to give out sooner or later, so why not move the office now so I don't have to go up and down steps?" he says. "When we put the desk down there, we made it wide enough so that a wheelchair will be able to get in there eventually."

Recently, Roth has put his will and estate papers in order. "You don't want to have to do that kind of stuff, but you gotta," he says.

Roth still attends his 10-year-old son's soccer games. But in anticipation of the day when that won't be possible, he's purchased a video camera, so he can see the game with his family when they return.

"The fortunate thing with this disease is you've got somewhat of a time frame," Roth says. "You've got the opportunity to plan these things out if you use your time right. If you do the planning, you've got that 'I've got that base covered' feeling. You've accomplished something, and you can go on to the next step." And, he hopes, to a better night's sleep.

How Sleepy Are You?

If you're very sleepy in the daytime, you may not be getting enough sleep at night. Or, as in the case of myotonic dystrophy, brain centers controlling sleepiness may not be functioning properly. This scale can help you determine whether your daytime sleepiness warrants a change in habits or medical attention.

The Epworth Sleepiness Scale
0 = would never doze
1 = slight chance of dozing
2 = moderate chance of dozing
3 = high chance of dozing

A score of 9 or more means you're very sleepy and should consider seeking advice from a professional.

The Epworth Sleepiness Scale was developed by Murray Johns at the Sleep Disorders Unit, Epworth Hospital, Melbourne, Victoria, Australia, and was first published in the December 1991 issue of the journal Sleep.

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