Our bodies carry out many autonomous or involuntary actions, such as breathing, blinking, and pumping blood. Some neurodegenerative diseases interfere with the body’s ability to automate these internal processes. One of these disorders is multiple system atrophy or MSA, a rare and devastating condition that shares many similarities with Parkinson’s. MSA affects the ability of nerve cells to communicate with the rest of the body and the voluntary nervous system functions that control movement. The condition only affects approximately four out of every 100,000 people.
Overview
Multiple system atrophy was first introduced to medical literature in 1969. The less-well-known cousin of Parkinson’s disease, the two share many symptoms, including a buildup of the same protein in the brain. For those with MSA, the part of the brain that controls the muscles and autonomic processes starts to shut down. This affects involuntary bodily functions such as bladder and muscle control, blood pressure, and breathing, as well as voluntary muscles.
Causes
Multiple system atrophy (MSA) seems to occur randomly and without discrimination towards ethnicity or gender. The hallmark of MSA is the degeneration of these areas in the brain and spinal cord:
- The basal ganglia, a collection of nerve cells deep in the brain, is responsible for controlling and smoothing out muscle movements and posture
- The cerebellum controls and coordinates voluntary movements and helps maintain balance.
- The autonomic system involves other regions of the brain that control involuntary movements
Although the cause of the degeneration is still unknown, theories suggest the accumulation of an abnormal protein, alpha-synuclein, in the brain. Alpha-synuclein helps the nerve cells communicate; too much abnormal of this protein interferes with these open lines of communication.
Symptom Clusters
The symptoms of MSA vary depending on the severity and the part of the brain that is most affected. The condition can be categorized into three symptom clusters: cerebellar, Parkinsonian, and autonomic. These clusters used to be considered three separate conditions — Shy-Drager syndrome, striatonigral degeneration, and sporadic olivopontocerebellar atrophy — but experts now recognize them as distinct presentations of MSA.
Cerebellar Symptom Cluster
About 20% of those with multiple system atrophy present with cerebellar degeneration. Since that part of the brain is in charge of coordinating body movements and balance, people with this type of MSA typically experience
- loss of coordination, particularly in tasks that require multiple actions at once
- inability to control arm and leg movements
- lack of balance
- difficulty walking
- trouble focusing their eyes on subjects
- difficulty reaching for objects
- feelings of instability even when sitting
- slurred speech
Parkinsonian Symptom Cluster
Roughly 60% of people with multiple system atrophy experience symptoms similar to those of Parkinson’s disease. Parkinsonian MSA occurs when the degeneration begins in the basal ganglia deep within the brain. Degeneration of this area, therefore, can result in:
- stiff or rigid muscles
- slow, shaky movements
- shuffling when walking and other gait issues
- increased risk of falling due to instability
- stooped posture
- trembling or jerky limbs when attempting to hold them still
- a high-pitched and quivering voice
- poor articulation
Autonomic System Cluster
The autonomic system keeps the body functioning efficiently without thought by controlling involuntary processes. When degeneration occurs in this system, people with multiple system atrophy can experience a wide range of distressing symptoms, including
- fainting, dizziness, lightheadedness
- fluctuating blood pressure (orthostatic hypotension)
- involuntary muscle contractions
- erectile or sexual dysfunction
- loss of bladder or bowel control
- constipation
- vision disturbances
- difficulty swallowing
- breathing problems
- sleep apnea and sleep disorders
- reduced sweat, tears and saliva leading to heat intolerance, dry mouth, and dry eyes
Diagnosis
Some doctors initially misdiagnose multiple system atrophy as Parkinson’s disease; however, if symptoms do not respond to Parkinson’s medications, the physician may start to suspect MSA. To diagnose MSA, he or she will take an MRI to check for changes in the brain. Assessing the function of the autonomic nervous system requires thermoregulatory sweat tests and blood pressure measurements testing for orthostatic hypotension or a sudden drop in blood pressure upon standing. If both the MRI and the autonomic tests show abnormalities, the doctor may then confirm a diagnosis of MSA.
Treatment
Treatment focuses on managing the symptoms of multiple system atrophy through medications, lifestyle changes, and disability accommodations. Doctors will recommend increasing salt and water intake and wearing compression stockings to deal with orthostatic hypotension. Eye drops can alleviate dry eye, and drugs can treat sexual dysfunction. Anticholinergic medications can address bladder control problems. Therapies help people with MSA adjust to speech and movement challenges and teach them to use any necessary mobility aids. In advanced stages of multiple system atrophy, some individuals require a breathing tube, feeding tube, or both.
Mortality
There is currently no cure for multiple system atrophy, and once the condition develops, the symptoms will get worse over time. More than half of people with MSA are bound to a wheelchair or severely disabled within five years after the onset of motor symptoms, and most do not live more than ten years after this point. Fatalities are usually due to respiratory failure or cardiac arrest.
Ongoing Research
Because multiple system atrophy is so rare, scientists and doctors have limited resources with which to experiment. Therefore, those with MSA often make arrangements before their death for the donation and harvesting of their brain to help further medical research into diagnostic testing, treatments, and a possible cure. Current medical research is focused on confirming causes, identifying risk factors and trait markers, learning to distinguish MSA from other neurodegenerative diseases, and the development of drugs to prevent or slow progression.