Multiple system atrophy is a progressive, fatal disorder that makes muscles stiff (rigid) and causes problems with movement, loss of coordination, and malfunction of internal body processes (such as blood pressure and bladder control).
Multiple system atrophy usually begins when people are in their 50s. It affects about twice as many men as women. It results from degeneration of several parts of the brain and spinal cord:
The cause of the degeneration is unknown.
Multiple system atrophy includes three disorders previously thought to be separate disorders:
Multiple system atrophy is a progressive disorder. Early symptoms vary, depending on which part and how much of the brain is affected first. The disorder causes three groups of symptoms.
Parkinsonism—symptoms that resemble those of Parkinson disease—may occur early. 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 also occur early. It results from degeneration in the cerebellum. People 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 early. Blood pressure may decrease dramatically when a person stands up, causing dizziness, light-headedness, or fainting—a condition called orthostatic hypotension. Blood pressure may increase when a person lies down. People may need to urinate urgently or frequently or may pass urine involuntarily (urinary incontinence). They may have difficulty emptying the bladder (urinary retention). Constipation is common. Vision becomes poor. Men may have difficulty initiating and maintaining an erection (erectile dysfunction).
Other symptoms of autonomic malfunction may occur early or late. 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). People may have vivid, frightening dreams that they sometimes act out while they are asleep. People may lose control of bowel movements (fecal incontinence).
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.
The diagnosis is based on symptoms. However, symptoms may resemble those of other disorders, making the disorder difficult to diagnose.
The only sure way to diagnose multiple system atrophy is to examine brain tissue after death. Nonetheless, some tests help with the diagnosis. For example, if the combination of levodopa plus carbidopa relieves parkinsonism, the cause is probably Parkinson disease. This combination has little or no lasting effect on similar symptoms due to multiple system atrophy. Magnetic resonance imaging (MRI) of the brain may help rule out other neurologic disorders.
Tests to evaluate the autonomic nervous system may be done. For example, blood pressure may be measured while the person is sitting and after the person stands to check for orthostatic hypotension. The presence of orthostatic hypotension supports the diagnosis of multiple system atrophy.
No treatment can cure multiple system atrophy. However, a combination of simple measures and drugs may help relieve symptoms.
As the disorder progresses, people may need a breathing tube, a 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 soon after the disorder is diagnosed. These directives should indicate what kind of medical care people want at the end of life (see Advance directives).
Last full review/revision July 2013 by Phillip Low, MD