Multiple system atrophy (MSA) is a slowly progressive neurodegenerative disease that afflicts approximately 25,000-75,000 Americans, with approximately 10,000 new cases diagnosed each year. The number of cases is hard to estimate because MSA is similar to other disorders and many patients do not get the correct diagnosis during their lifetime.
MSA is one of the parkinsonian disorders that starts with non-motor symptoms and sleep disturbances.
The autonomic nervous system is the body's internal system that controls most of the involuntary functions of the body. Examples of this include: controlling urinary bladder function, maintaining blood pressure, and controlling breath and heart rate, and bowel motion. The failure of the function of this system is called "dysautonomia."
Studies have shown that blood pressure, urinary bladder and genital organs are affected early by MSA. The autonomic nervous system normally works to increase blood pressure when standing up quickly from a sitting or lying position to maintain blood supply to the brain. But
orthostatic hypotension occurs when the autonomic system fails, which can result in feeling about to faint, fatigue, tiredness or a partial or complete loss of consciousness. The main danger is the risk of falls and fall-related consequences.
Other examples of dysautonomia affecting the urinary bladder include: increased urinary frequency, urinary urgency, and feeling of incomplete urinary bladder emptying. The inability to maintain erection during sexual intercourse or losing morning erection could also occur as early manifestation of the disease.
Sleep disorders in MSA include rapid eye movement sleep behavior disorder (RBD), fragmented sleep, restless leg syndrome (RLS), and excessive daytime sleepiness. RBD is the most common among these symptoms, which usually precedes motor symptoms or may occur with its onset. It involves abnormal behavior during the sleep phase with rapid eye movement (REM sleep) in which the content of the dreams can be vivid, violent, and frightening and patients may act out their dreams. Obstructive sleep apnea (OSA), a frequent cessation of breath during sleep, may also occur.
MSA is one of the atypical parkinsonian syndromes. As in Parkinson's disease, MSA is characterized by slowness of movement that may lead to an increase in the amount of time needed to accomplish the activities of daily living (bradykinesia), decrease in amplitude of movement that may lead to decrease associated movements when walking, lower tone of voice (hypophonia), and stiffness of the muscles (rigidity). People with MSA may develop tremor, clumsiness, early shuffling gait, and frequent falls.
MSA has two main forms, depending on which symptoms are most prominent at the time we examine a person:
- The parkinsonian type (MSA-P), has primary characteristics similar to Parkinson's disease (such as moving slowly, stiffness, and tremor) along with problems of balance, coordination, and autonomic nervous system dysfunction
- The cerebellar type (MSA-C), features ataxia (problems with balance and coordination), difficulty swallowing, speech abnormalities or a quavering voice, and abnormal eye movements. Cerebellar relates to the part of the brain that controls coordination.
Both forms of MSA have similar survival rates, but MSA-P may affect quality of life more. Commonly, patients may end up having both parkinsonism and cerebellar features.