A Good Night’s Rest
To millions of Americans suffering from chronic pain, a good night's sleep often proves to be the elusive dream. Pain-induced sleep disturbances can range from difficulty initially going to sleep to bouts of fitful sleep throughout the night. Other people awaken in the early hours of the morning and lie in the dark waiting for the alarm to go off, knowing that a return to sleep is impossible. Insomnia can be caused by a variety of problems, including physical conditions, such as restless leg syndrome or respiratory ailments.
While many people experience an occasional sleep disturbance and find it a troubling — albeit minor — annoyance, millions of people suffer from chronic, habitual insomnia due to one cause or another. If fact, statistics show that an estimated 40 million Americans are afflicted by sleep disorders, and in the past year, almost two-thirds of American adults experienced some type of sleep problem a few times per week.
In this country alone, sleep-deprived employees cost their employers an estimated $70 billion each year.
Michael Cawley, PharmD, RRT, CPFT, describes sleep as part of the restorative process that our bodies cycle through daily. "Various neurochemicals that affect multiple systems throughout our bodies are regulated and produced both during wakefulness and during sleep," he notes. "The basic explanation for sleep is that everyone needs it to maintain emotional and physical health."
In fact, humans are actually programmed for two intervals of sleep in every 24-hour period — once at night and again in mid-afternoon. "If you lived in Europe, you'd be napping in the afternoon," says Robert Doekel, MD. "We've got it wrong here in America and the Europeans have it right." As the medical director of the Sleep Disorders Center at Health South in Birmingham, Ala., Dr. Doekel has been in the field of sleep research for more than 20 years. He continues, "it really does affect us if we don't satisfy that urge to get a quick power nap in the afternoon."
"The exact reason people sleep remains an elusive question," adds Thomas Kilkenny, DO, FAASM, FCCP, the director of the Sleep Center at Staten Island University Hospital in Staten Island, New York. "We do know that sleep deprivation leads to a multitude of abnormalities including fatigue, sleepiness, memory impairment, and difficulty concentrating. As sleep deprivation continues, more abnormalities occur that can ultimately lead to death. Sleep deprivation has even been used as a form of torture."
When pain is a causative factor in sleep disruption, the problem becomes more complicated. What is causing the pain? When is it occurring? Is it hindering the patient from falling asleep, or does it awaken him or her in the middle of the night? Some pain is benign, caused by a transient problem or acute injury, such as a sprained ankle. Other pain is more insidious. For example, bone pain in the night may indicate cancer. On the other hand, it may suggest an arthritic condition. Since any number of factors can cause sleep disturbances, clinicians need to discard the traditional treatment plan for insomnia when pain figures into the mix. The paradigm has to shift from simply getting the patient to sleep to alleviating pain so the patient can go to sleep and stay asleep.
"The first thing that needs to be done," notes Dr. Cawley, "is to determine the cause of the pain. Once the pain is properly diagnosed, the clinician can determine the appropriate prescription and then titrate it to the right dosage with limited side effects."
Pain can disrupt any stage of sleep, but Dr. Doekel indicates that it generally occurs during one of the lighter stages of sleep or even between stages, since that is when most sleepers tend to shift positions. He also points out that pain keeps people from sinking into the deeper stages of sleep, so they feel less rested in the morning, even though it appears they slept for a full eight hours. The amount of sleep a person gets is not enough, as all of these doctors point out; the key is the quality of that sleep.
When pain is a causative factor in sleep disruption, the problem becomes more complicated. What is causing the pain? When is it occurring?
There are four initial stages of NREM — or non-rapid eye movement — sleep, each determined via different EEG waveforms. Stage 1 is the lightest stage, while Stages 3 and 4 — or Delta sleep — are much deeper. "Delta sleep is the stage where it is most difficult to awaken patients from sleep," states Dr. Kilkenny. "When patients do awaken, they are often groggy and confused, while patients who awaken from Stage 1 sleep may not even be aware they were asleep at all."
REM — or rapid-eye movement — sleep is the last stage that follows NREM sleep. This is when people dream, as well as when the brain appears to be most active, and ideally occurs about four to six times per night. "The EEG appears as if the patient is awake, but the body is actually paralyzed," remarks Dr. Kilkenny. "Some people believe that the body rests during REM sleep, while the mind rests in Delta sleep."
A balance between REM and NREM stages is crucial. "People should spend 75 percent of the time in NREM and 25 percent in REM. A patient must enter REM sleep to regulate neurochemicals for proper metabolic function," stresses Dr. Cawley.
Certain pain conditions are especially problematic for clinicians treating sleep disorders. Two of these are restless leg syndrome and fibromyalgia. "If you send a fibromyalgia patient to a rheumatologist, he'll say that the sleep disturbance is causing the patient's pain. But if you send the patient to a sleep specialist, he'll say the pain is disrupting sleep," comments Dr. Doekel. If fibromyalgia is involved in a sleep disorder, treatment is much more difficult. "Several things have been tried — benzodiazepines, antidepressants," he continues, "and nothing works really well."
In restless leg syndrome, the patient perceives pain, aching, or a crawling sensation in the lower extremity and moves the legs in an attempt to get rid of it, leading to sleep disturbances. "For this condition, we use the same drugs that are used to treat Parkinson's disease, which are dopamine agonists." For these two conditions, long-term treatment is often needed, but most other conditions require only short-term therapy.
Dr. Cawley also points out that a variety of pulmonary diseases can interfere with sleep, including asthma, chronic obstructive pulmonary disease (COPD), and congestive heart failure, where the heart's inability to function properly allows fluid to build up in the lungs. The patient often sits up at night, since lying down increases the fluid buildup and leads to dyspnea.