Multiple Sclerosis and Sleep
Multiple Sclerosis (MS) is a disorder in which the body's immune system attacks and destroys myelin, a membrane that covers axons in the brain and spinal cord. Myelin serves both to protect axons and to speed the conduction of electrical impulses along nerve fibers. The destruction of myelin results in scarring and loss of nerve cells and can lead to a whole host of symptoms for MS patients, including paralysis, depression, loss of memory, fatigue and problems with vision, balance, bladder and bowel control. However, because it is a disease that progresses slowly, MS can be very mild for some patients and many people with MS are able to lead full and active lives.
According to the National Institute of Neurological Disorders and Stroke at the National Institutes of Health, MS is more common in women than men and is more than twice as likely to affect white people than people of other races. Also, the prevalence of MS among people in the more northerly climate zone is five times higher than for people in the tropics. The cause of MS is unknown but environmental, viral and genetic causes may play a role. MS is not fatal or contagious, although severe symptoms may lead to a shortened or decreased quality of life for some people.
Fatigue, one of the most common symptoms of MS, can be profoundly disabling. The cause of fatigue in MS is not well understood but some researchers believe that the degree of fatigue felt by MS patients is an indication of how far along the disease has progressed. However, a recent study conducted by researchers from Pennsylvania State University found that depression and sleep disturbance were stronger predictors of fatigue in MS patients than disease severity. Specifically, the results of this study showed that all three contribute to fatigue in MS, but that sleep disturbance is the biggest contributor.
MS is also associated with a number of sleep disorders. According to a study led by W. Elon Fleming, MD, at the Sleep Disorders Center at Island Hospital in Anacortes, Washington, the most common sleep disorders in MS patients are insomnia, nocturnal leg spasms, narcolepsy, REM sleep behavior disorder, and sleep disordered breathing. Restless legs syndrome (RLS) is also highly prevalent among MS patients. One study revealed that among 156 MS patients, 51% met the criteria for RLS based on neurological examination and medical interview and that RLS was associated with higher MS-related disability. Medications used to treat MS may also cause or worsen these problems. The study also showed that pain, medications and frequent nighttime urination influenced sleep among MS patients.
Reducing fatigue and improving sleep is critical to improving the lives of people with MS. There are many options for improving sleep, including both behavioral and pharmaceutical remedies. It is very important that physicians screen for sleep problems among their MS patients and that they are aware of the options to treat them.
Initial symptoms of MS may be brief and mild and usually first occur in people between the ages of 20 and 40. Each MS patient has a unique set of symptoms, depending on where in the brain the destruction of myelin occurs. Some patients are most affected by severe fatigue while others complain of blurred vision and loss of balance. Still others may suffer most profoundly due to loss of bladder and bowel control. MS patients might experience any of these and other symptoms either fully or partially while others go for months or years with no symptoms whatsoever. Another feature of the disease is unpredictability; MS patients may have severe symptoms one day and be symptom-free the next.
Many of the body's essential functions depend on the brain and spinal cord, at least as a relay station, and damage to it in people with MS results in a wide variety of symptoms. Here are some of the most common:
- Visual impairments – eye twitching, blurred vision, double vision, loss of color vision, blindness
- Muscular effects – weakness, loss of muscle tone, slurred speech, muscle contractions, foot drop, paralysis
- Sensory symptoms – numbness, tingling, pain, burning, itching, loss of awareness of location of body parts
- Coordination and balance – loss of coordination or balance, shaking, over or undershooting limb movements, nausea, vomiting, stuttering, loss of ability to move to a rhythm
- Bowel, bladder and sexual dysfunction – urinary incontinence, bowel incontinence, impotence, lack of ability to achieve orgasm
- Cognitive abnormalities – short and long-term memory problems, speech impairments
- Mood disorders - mood swings, anxiety, depression
- Sleep disorders – insomnia, nocturnal movements, sleep disordered breathing, narcolepsy, and REM sleep behavior disorder
- Other – epileptic seizures, problems breathing, acid reflux, impaired taste and smell, difficulty swallowing, problems regulating heat and cold, fatigue
There is no single test for MS. When a person seeks treatment for MS-related symptoms, a doctor will consider neurological exams, laboratory tests and the patient's medical history to confirm the diagnosis. The clinical diagnosis is usually confirmed by an MRI examination of the brain.
There is no cure for MS at the present time. The goal in treating MS is to limit the destruction of myelin, which typically requires suppression of the body's immune system. If you are diagnosed with MS, your doctor may prescribe pharmaceutical therapies that achieve this and address your related symptoms. However, some people with MS lead healthy lives without any treatment at all.
Because of its connection to symptom severity, sleep problems should be given special consideration in MS patients. There are many options for improving sleep, including both behavioral and pharmaceutical remedies. If you have MS and are suffering from sleep problems, talk to your doctor about diagnosing and treating them.
Getting a good night's sleep helps to alleviate many common symptoms of MS, including chronic fatigue, mood and memory problems. Daytime naps can also help, but only if napping does not interfere with night-time sleep.
Evidence suggests that exercise can reduce fatigue symptoms as well as muscle control and balance problems. Some MS patients report a worsening of symptoms caused by warm weather or body heat that results from heavy exercise. If this occurs, try taking a cold bath or going swimming.
Some people report that alternative therapies have helped with MS symptoms, though there is no scientific data to support such claims.
When a person is diagnosed with MS, his or her life may be disrupted. His or her career or education may be jeopardized by the onset of MS symptoms at a time when treatment costs are at their highest. This can be a difficult situation to cope with.
Reviewed by Mark Mahowald, MD, and Robert Y. Moore, MD, PhD.