The parts of the brain that control movements and many internal body processes degenerate.
Symptoms include symptoms that resemble those of Parkinson disease, low blood pressure when a person stands (orthostatic hypotension), problems with urination, and constipation.
Doctors base the diagnosis on a person's response to levodopa (used to treat Parkinson disease) and results of magnetic resonance imaging and tests of autonomic function.
Simple measures and drugs can help lessen symptoms, but the disorder is progressive and ultimately fatal.
(See also Overview of the Autonomic Nervous System Overview of the Autonomic Nervous System The autonomic nervous system regulates certain body processes, such as blood pressure and the rate of breathing. This system works automatically (autonomously), without a person’s conscious... read more .)
Multiple system atrophy usually begins when people are in their 50s. It affects about twice as many men as women.
There are two types of multiple system atrophy (MSA), based on which symptoms occur first:
MSA-C is characterized by loss of coordination and difficulty maintaining balance, which indicates cerebellar dysfunction (indicated by the C).
MSA-P is very similar to Parkinson disease (indicated by the P) except that tremor often does not develop and levodopa often does not relieve symptoms.
Both types involve autonomic nervous system dysfunction. Although multiple system atrophy begins as one of these types, symptoms of the other type eventually develop. After about 5 years, symptoms tend to be similar regardless of which disorder developed first.
Causes of MSA
Multiple system atrophy results from degeneration of several parts of the brain and spinal cord:
The basal ganglia (collections of nerve cells at the base of the cerebrum, deep within the brain), which help control voluntary muscle movements by balancing the actions of muscle groups that move the same muscles in opposite ways (for example, a group that bends an arm and a group that straightens the arm)
The cerebellum, which coordinates voluntary movements (particularly complex movements done simultaneously) and helps maintain balance
Areas that control the autonomic nervous system, which regulates involuntary body processes, such as how blood pressure changes in response to changes in posture
The cause of the degeneration is unknown, but degeneration in multiple system atrophy probably results when synuclein changes shape (misfolds) and accumulates in support cells in the brain. Synuclein is a protein in the brain that helps nerve cells communicate, but whose function is not yet fully understood. Abnormal synuclein can also accumulate in people with pure autonomic failure Pure Autonomic Failure Pure autonomic failure is dysfunction of many of the processes controlled by the autonomic nervous system, such as control of blood pressure. It is not fatal. Pure autonomic failure is caused... read more , Parkinson disease Parkinson Disease (PD) Parkinson disease is a slowly progressive degenerative disorder of specific areas of the brain. It is characterized by tremor when muscles are at rest (resting tremor), increased muscle tone... read more , or dementia with Lewy bodies Dementia With Lewy Bodies and Parkinson Disease Dementia Dementia with Lewy bodies is progressive loss of mental function characterized by the development of Lewy bodies in nerve cells. Parkinson disease dementia is loss of mental function characterized... read more .
Rapid eye movement (REM) sleep behavior disorder Rapid eye movement sleep behavior disorder Parasomnias are unusual behaviors that occur just before falling asleep, during sleep, or when waking up. (See also Overview of Sleep.) Various unconscious and largely unremembered behaviors... read more often occurs in people with disorders that involve accumulation of synuclein, including multiple system atrophy.
Locating the Cerebellum and Basal Ganglia
The cerebellum is located below the cerebrum just above the brain stem. The cerebellum coordinates the body’s movements. With information it receives from the cerebral cortex and the basal ganglia about the position of the limbs, the cerebellum helps the limbs move smoothly and accurately. (The cerebral cortex is the convoluted layer of tissue that forms the outer surface of the cerebrum. It contains most of the nerve cells in the nervous system.)
The basal ganglia are collections of nerve cells located deep within the brain. They include the following structures:
The basal ganglia help smooth out muscle movements and coordinate changes in posture.
Symptoms of MSA
Multiple system atrophy is a progressive disorder. Early symptoms of multiple system atrophy vary, depending on which part and how much of the brain is affected first. The disorder causes three groups of symptoms.
Parkinsonism Parkinsonism Parkinsonism refers to symptoms of Parkinson disease (such as slow movements and tremors) that are caused by another condition. Parkinsonism is caused by brain disorders, brain injuries, or... read more —symptoms that resemble those of Parkinson disease—may occur. These symptoms result from degeneration in the basal ganglia. Muscles are stiff (rigid), and movements become slow, shaky, and difficult to initiate. When walking, people may shuffle and not swing their arms. People feel unsteady and off balance, making them more likely to fall. Posture may be stooped. Limbs may tremble jerkily, usually when they are held in one position. But people with multiple system atrophy are less likely to have tremors during rest than people with Parkinson disease. Articulating words is difficult, and the voice may become high-pitched and quaver.
Loss of coordination may occur. It results from degeneration in the cerebellum. People lose their balance. Later, they may be unable to control movements of their arms and legs. Consequently, they have difficulty walking and take wide, irregular steps. When reaching for an item, they may reach beyond it. When sitting, they may feel unstable. People may have difficulty focusing their eyes on and following objects. Tasks that require rapidly alternating movements, such as turning a door knob or screwing in a light bulb, also become difficult.
Malfunction of internal body processes, controlled by the autonomic nervous system, may also occur. Blood pressure may decrease dramatically when a person stands up, causing dizziness, light-headedness, or fainting—a condition called orthostatic hypotension Dizziness or Light-Headedness When Standing Up In some people, particularly older people, blood pressure drops excessively when they sit or stand up (a condition called orthostatic or postural hypotension). Symptoms of faintness, light-headedness... read more . Blood pressure may increase when a person lies down.
People may need to urinate urgently or frequently or may pass urine involuntarily (urinary incontinence Urinary Incontinence in Adults Urinary incontinence is involuntary loss of urine. Incontinence can occur in both men and women at any age, but it is more common among women and older people, affecting about 30% of older women... read more ). They may have difficulty emptying the bladder (urinary retention Urinary Retention Urinary retention is inability to urinate or incomplete emptying of the bladder. People who have incomplete emptying of the bladder may have urinary frequency or urinary incontinence. If the... read more ). Constipation Constipation in Adults Constipation is difficult or infrequent bowel movements, hard stool, or a feeling that the rectum is not totally empty after a bowel movement (incomplete evacuation). (See also Constipation... read more is common. Vision becomes poor. Men may have difficulty initiating and maintaining an erection (erectile dysfunction Erectile Dysfunction (ED) Erectile dysfunction (ED) is the inability to attain or sustain an erection satisfactory for sexual intercourse. (See also Overview of Sexual Dysfunction in Men.) Every man occasionally has... read more ).
Other symptoms of autonomic malfunction may include the following:
Less sweat, tears, and saliva are produced. As a result, people may become intolerant of heat and have dry eyes and mouth.
People may have difficulty swallowing and breathing.
Breathing may be noisy and high-pitched.
During sleep, breathing may stop repeatedly or become inadequate (sleep apnea Sleep Apnea Sleep apnea is a serious disorder in which breathing repeatedly stops long enough to disrupt sleep and often temporarily decrease the amount of oxygen and increase the amount of carbon dioxide... read more ).
If REM sleep behavior disorder develops, people speak (often profanely) and may wave their arms or legs violently during sleep, possibly because they are acting out vivid, frightening dreams.
Many people are confined to a wheelchair or are otherwise severely disabled within 5 years after symptoms begin. The disorder results in death 9 to 10 years after symptoms begin.
Diagnosis of MSA
A doctor's evaluation
Magnetic resonance imaging
Tests to evaluate the autonomic nervous system
The diagnosis of multiple system atrophy is based on a doctor's evaluation and results of certain tests. For example, doctors may suspect multiple system atrophy if parkinsonian symptoms are rapidly worsening and levodopa (used to treat Parkinson disease) has little or no effect on symptoms.
Magnetic resonance imaging (MRI) is usually done to check for certain changes in the brain.
Tests to evaluate the autonomic nervous system Diagnosis The autonomic nervous system regulates certain body processes, such as blood pressure and the rate of breathing. This system works automatically (autonomously), without a person’s conscious... read more are done. They include the thermoregulatory sweat test and measurement of blood pressure while the person is sitting and after the person stands to check for orthostatic hypotension.
If MRI shows changes that suggest multiple system atrophy and test results are abnormal, multiple system atrophy is likely.
Treatment of MSA
No treatment can cure multiple system atrophy. However, a combination of simple measures and drugs may help relieve symptoms.
Parkinsonism Treatment Parkinsonism refers to symptoms of Parkinson disease (such as slow movements and tremors) that are caused by another condition. Parkinsonism is caused by brain disorders, brain injuries, or... read more : Continuing to do as many daily activities as possible helps maintain muscle strength and flexibility. Stretching and exercising regularly may also help. Drugs used to treat Parkinson disease, such as levodopa plus carbidopa, taken by mouth, may be tried, but this combination usually has little effect or is effective for only a few years.
Orthostatic hypotension: Measures are taken to stabilize the sudden changes in blood pressure. Consuming more salt and water may increase the volume of blood and thus help increase blood pressure. Standing up slowly may help prevent blood pressure from decreasing too much or too fast when a person stands, as may wearing an abdominal binder or compression stockings. These garments help maintain blood pressure by promoting blood flow from the legs to the heart and thus prevent too much blood from staying (pooling) in the legs. Raising the head of the bed by about 4 inches (10 centimeters) can help prevent blood pressure from increasing too much when the person lies down. Fludrocortisone may be taken by mouth. It helps the body retain salt and water and thus may increase blood pressure as needed when a person stands. Other drugs, such as midodrine or droxidopa, taken by mouth, may also help.
Decreased production of body fluids: If sweating is reduced or absent, people should avoid warm environments to avoid overheating the body. Good dental care and regular check-ups are essential for people with dry mouth. Artificial tears (eye drops containing substances that resemble real tears) applied every few hours may relieve dry eyes.
Urinary retention Treatment Urinary retention is inability to urinate or incomplete emptying of the bladder. People who have incomplete emptying of the bladder may have urinary frequency or urinary incontinence. If the... read more : If needed, people can learn to insert a catheter (a thin rubber tube) into the bladder themselves. They insert it several times a day. It is inserted through the urethra, allowing urine in the bladder to drain out. People remove the catheter after the bladder is empty. This measure helps prevent the bladder from stretching and urinary tract infections from developing. Washing the hands, cleansing the area around the urethra, and using a sterile or clean catheter also help prevent infections. Inserting a catheter becomes more difficult as coordination deteriorates. Sometimes drugs such as bethanechol are used to stimulate contractions of the bladder and thus help the bladder empty.
Urinary incontinence Treatment Urinary incontinence is involuntary loss of urine. Incontinence can occur in both men and women at any age, but it is more common among women and older people, affecting about 30% of older women... read more : Oxybutynin, mirabegron, tamsulosin, or tolterodine, taken by mouth, may be used to relax the muscles of an overactive bladder. If incontinence persists, using a catheter inserted into the bladder may help. People may learn to insert it themselves.
Constipation Treatment Urinary incontinence is involuntary loss of urine. Incontinence can occur in both men and women at any age, but it is more common among women and older people, affecting about 30% of older women... read more : A high-fiber diet and stool softeners are recommended. If constipation persists, enemas may be necessary.
Erectile dysfunction Treatment Erectile dysfunction (ED) is the inability to attain or sustain an erection satisfactory for sexual intercourse. (See also Overview of Sexual Dysfunction in Men.) Every man occasionally has... read more : Usually, treatment consists of drugs such as sildenafil, tadalafil, vardenafil, or avanafil, taken by mouth.
As the multiple system atrophy progresses, people may need a breathing tube, feeding tube (usually surgically inserted), or both.
Physical, occupational, and speech therapists can teach people ways to compensate when walking, doing daily activities, and speaking become difficult. Social workers can help people find support groups and, when symptoms become disabling, home health care or hospice services.
Because the disorder is progressive and ultimately fatal, people should prepare advance directives Advance Directives Health care advance directives are legal documents that communicate a person’s wishes about health care decisions in the event the person becomes incapable of making health care decisions. There... read more soon after the disorder is diagnosed. These directives should indicate what kind of medical care people want at the end of life.