Multiple-System Atrophy (MSA)

By Sally Robertson, BSc

Aug. 11, 2016

Multiple-system atrophy (MSA) is a progressive neurological condition in which specific areas of the brain undergo neural degeneration. The three brain areas primarily affected are the brain stem, basal ganglia and cerebellum, portions of the brain that regulate bodily functions and motor control.

Previously referred to as Shy-Drager syndrome, this condition presents with many symptoms similar to those seen in Parkinson’s disease such as poor balance and movement control and loss of automatic functions such as blood pressure, bladder and bowel control. Although MSA often presents similarly to Parkinson’s disease, it does not respond to any of the treatments for Parkinson’s disease. MSA also tends to progress more quickly than Parkinson’s disease, with patients not usually surviving for more than 7 or 8 years after diagnosis.

Cause

It is not yet clear what causes nerve cells to become damaged in MSA. Nerve cells in the affected brain areas deteriorate and shrink (atrophy). Microscopy studies have shown that structures referred to as glial inclusion bodies are seen in cells affected by this atrophy and that these bodies over-express a protein called alpha-synuclein. Mutation of the synuclein gene, SNCA, which codes for alpha-synuclein, is a potential risk factor for MSA. It is not yet clear whether or not environmental factors play a role.

Recent estimates suggest that the prevalence of MSA is about 5 people per 100,000, which translates as almost 3,000 individuals living with the condition in the U.K at any one time. Parkinson’s disease is much more common, affecting around 200 per 100,000 people in the UK. MSA usually starts to present with symptoms between the ages of 50 and 60 years and then advances rapidly over the course of 5 to 10 years.

Symptoms

The first symptoms of MSA are often difficult to distinguish from those of Parkinson’s disease and include the following:

• Slowed movement, rigidity and tremor
• Impaired speech and quivering voice
• Clumsiness and lack of coordination
• Problems controlling the bladder, with urgency to urinate or difficulty emptying the bladder
• Orthostatic hypotension, where blood pressure drops when standing up from a sitting or lying position

MSA is divided into two types, depending on what the most prominent symptoms are. These are described below:

The parkinson type - Here, the main features of disease are those that resemble the symptoms seen in Parkinson’s disease such as slowed movement, stiffness, tremor, poor coordination, problems with balance and autonomic nervous system dysfunction.

The cerebellar type - Cerebellar refers to the cerebellum, the brain area involved in coordination. The primary symptoms of this type are ataxia, abnormal speech or quivering voice, difficulty swallowing and abnormal eye movements.

Additional general symptoms of MSA include the following:

• Contractures in the hands or limbs
• Involuntary gasping or sighing
• Antecollis, where the neck bends and the head droops
• Constipation, incontinence
• Reduced perspiration and reduced production of saliva and tears
• Impaired temperature regulation causing cold feet and abnormal sweating
• Agitated sleep and abnormal breathing pattern during sleep
• Impotence, lack of libido
• Irregular heart rhythm
• Depression, anxiety

Diagnosis and treatment

The diagnosis of MSA can be challenging due to symptoms of the condition being shared with other disorders. After checking a patient’s medical history and performing a neurological examination, a doctor may order tests to assess autonomic function such as control of heart rate, blood pressure and bladder function. They may also arrange an MRI scan to check for brain lesions that may be triggering MSA symptoms. Patients with MSA do not experience continued improvement when taking a drug for Parkinson’s disease called levodopa, a finding that can support an MSA diagnosis.

Although there are currently no drugs that can cure MSA, medications are available that can alleviate symptoms and help to manage the condition. Fludrocortisone or midodrine are often used to correct the orthostatic hypotension that can increase the risk of fainting and injury. A drug called dihydroxyphenylserine can help to replace the loss of neurotransmitters in the autonomic nervous system. A high-fibre diet and laxatives may be recommended to help constipated patients and anticholinergic treatment can help improve poor bladder control.

Other treatments and approaches that may be used to manage the symptoms of MSA include the following:

• Melatonin, clonazepam or antidepressants to help with sleep problems
• Speech therapy to address speech problems and swallowing difficulties
• Physiotherapy to sustain mobility, reduce contractures and decrease abnormal posture and spasms
• Walking aids or wheelchairs to aid mobility
• Occupational therapy to develop safe ways of carrying out day-to-day activities such as washing, dressing and cooking.

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