Multiple system atrophy
Multiple system atrophy is a degenerative disorder characterized by progressive damage to the autonomic nervous system (the portion of the nervous system that controls involuntary functions such as blood pressure, heart rate, digestion and sexual function), muscle tremor and rigidity, slow movement, and other widespread neurologic losses. The term "Multiple System Atrophy" is synonymous with striatonigral degeneration (SND) when Parkinsonism predominates,
olivopontocerebellar atrophy (OPCA) when cerebellar signs predominate, and Shy-Drager syndrome when autonomic failure is dominant. The Parkinsonism of MSA is generally an akinetic rigid syndrome, similar to that of PSP. Rest tremor may occur but is not a predominant feature. Postural instability is common. Parkinsonism is generally the most common initial sign and eventually develops in about 90% of all patients.
Multiple system atrophy (MSA) is a rare degenerative condition. It is a condition that appears similar to Parkinson's disease in that patients may be slow moving, tremulous and have a shuffling gait but with more widespread neurologic damage and damage to the autonomic nervous system (the portion of the nervous system that controls involuntary functions). The cause is unknown. There is progressive damage (degeneration) of the nervous system, with damage to all parts of the nervous system. The disorder develops gradually. It is most often diagnosed in men over 60 years old.
Symptoms of MSA vary in distribution, onset and severity from person to person. Because of this, three different diseases were initially described to encompass this range of symptoms: Shy-Drager syndrome, striatonigral degeneration, and olivopontocerebellar atrophy. In Shy-Drager syndrome, the most prominent symptoms are those involving the autonomic system, the body system that regulates blood pressure, urinary function, and other functions not involving conscious control. Striatonigral degeneration causes parkinsonian symptoms such as slowed movements and rigidity, while olivopontocerebellar atrophy principally affects balance, coordination, and speech.
MSA usually is diagnosed in people in their 50s to 70s. The condition occurs twice as often in men as women. For men, predominant symptoms early in the disease are the parkinsonian symptoms and the autonomic dysfunction problems such as unrelenting constipation and sexual impotence. Shy-Drager may be difficult to diagnose in the early stages because it can take years for key symptoms to develop. For most patients, the unstable, fluctuating blood pressure causes severe headaches. The fluctuating blood pressure also makes the condition difficult to treat. Medications are used to control some symptoms. Dietary changes, such as increasing salt and fluid intake, may help elevate blood pressure. A breathing or feeding tube may have to be surgically inserted to manage swallowing and breathing difficulties. Most people who are diagnosed with Shy-Drager syndrome die within seven to 10 years after symptoms begin. Pneumonia is the most common cause of death, although irregularities in heartbeat or choking may be responsible for death in some patients.
There is no cure for MSA, and there is no known means to slow progression. Treatment is aimed at controlling symptoms such as postural hypotension and parkinsonian movements. Anticholinergic medications may be used to reduce early or mild tremors. Levodopa may improve movement and balance. Carbidopa may reduce the side effects of Levodopa and make it work better. However, the response to medications may be disappointing. Many affected individuals respond poorly to treatment with anticholinergics or Levodopa. A pacemaker programmed to stimulate the heart to beat at a rapid rate (faster than 100 beats per minute) may increase blood pressure for some people. |