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Multiple System Atrophy (MSA)


Elizabeth Coon

, MD, Mayo Clinic

Reviewed/Revised Jul 2023
Topic Resources

Multiple system atrophy is a progressive, fatal disorder that causes symptoms resembling those of Parkinson disease (parkinsonism), loss of coordination, and malfunction of internal body processes (such as blood pressure and bladder control).

  • The parts of the brain that control movements and many internal body processes degenerate.

  • Symptoms include symptoms that resemble those of Parkinson disease, loss of coordination, 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 medications can help lessen symptoms, but the disorder is progressive and ultimately fatal.

Multiple system atrophy usually begins when people are in their 50s. It affects men and women equally.

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 the usual 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 Multiple System Atrophy

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

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:

  • Caudate nucleus (a C-shaped structure that tapers to a thin tail)

  • Putamen

  • Globus pallidus (located next to the putamen)

  • Subthalamic nucleus

  • Substantia nigra

The basal ganglia help smooth out muscle movements and coordinate changes in posture.

Locating the Basal Ganglia

Symptoms of Multiple System Atrophy

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.

Other symptoms of autonomic malfunction may include the following:

Many people are confined to a wheelchair or are otherwise severely disabled within 5 years after symptoms begin. The disorder results in death usually about 9 to 10 years after symptoms begin.

Diagnosis of Multiple System Atrophy

  • 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 Diagnosis 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 Multiple System Atrophy

  • Symptom relief

No treatment can cure multiple system atrophy. However, a combination of simple measures and medications may help relieve symptoms.

As the multiple system atrophy progresses, some people 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. Specialists in palliative medicine focus on relieving pain and treating symptoms and helps people deal with end-of-life issues. Social workers can help people find support groups and, when symptoms become disabling, home health care or hospice services.

End-of-life issues

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.

Drugs Mentioned In This Article

Generic Name Select Brand Names
INBRIJA, Larodopa
Orvaten, ProAmatine
Duvoid , Urecholine, Urecholine Solution
Ditropan, Ditropan XL, Gelnique , Oxytrol, Oxytrol for Women
Detrol, Detrol LA
LiQrev, Revatio, Viagra
Adcirca, ALYQ, Cialis, Tadliq
Levitra, Staxyn
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