Atypical Parkinsonism (PSP, MSA, CBD)
What is Atypical Parkinsonism?
Atypical Parkinsonism disorders are progressive diseases that present with some of the signs and symptoms of Parkinson's disease, but they generally do not respond well to drug treatment with levodopa. They are associated with abnormal protein buildup within brain cells. Listed below are descriptions and symptoms for PSP-Progressive Supranuclear Palsy, MSA-Multiple System Atrophy and CBD-Corticobasal Degeneration.
Progressive supranuclear palsy is a brain disorder that affects movement, vision, speech, and thinking ability (cognition). The signs and symptoms of this disorder usually become apparent in mid- to late adulthood, most often in a person's 60s. Most people with progressive supranuclear palsy survive 5 to 9 years after the disease first appears, although a few affected individuals have lived for more than a decade.
Loss of balance and frequent falls are the most common early signs of progressive supranuclear palsy. Affected individuals have problems with walking, including poor coordination and an unsteady, lurching gait. Other movement abnormalities develop as the disease progresses, including unusually slow movements (bradykinesia), clumsiness, and stiffness of the trunk muscles. These problems worsen with time, and most affected people ultimately require wheelchair assistance.
Symptoms of PSP include:
- Loss of balance
- Changes in personality
- Weakness of eye movements, especially in the downward direction
- Weakened movements of the mouth, tongue, and throat
- Slurred speech
- Difficulty swallowing
Progressive supranuclear palsy is also characterized by abnormal eye movements, which typically develop several years after the other movement problems first appear. Restricted up-and-down eye movement (vertical gaze palsy) is a hallmark of this disease. Other eye movement problems include difficulty opening and closing the eyelids, infrequent blinking, and pulling back (retraction) of the eyelids. These abnormalities can lead to blurred vision, an increased sensitivity to light (photophobia), and a staring gaze.
Additional features of progressive supranuclear palsy include slow and slurred speech (dysarthria) and trouble swallowing (dysphagia). Most affected individuals also experience changes in personality and behavior, such as a general loss of interest and enthusiasm (apathy). They develop problems with cognition, including difficulties with attention, planning, and problem solving. As the cognitive and behavioral problems worsen, affected individuals increasingly require help with personal care and other activities of daily living.
Estimates vary, but only about three to six in every 100,000 people worldwide, or approximately 20,000 Americans, have PSP—making it much less common than Parkinson's disease (another movement disorder in which an estimated 50,000 Americans are diagnosed each year).
PSP was first described as a distinct disorder in 1964, when three scientists published a paper that distinguished the condition from Parkinson's disease. It was sometimes referred to as Steele-Richardson-Olszewski syndrome, reflecting the combined names of the scientists who defined the disorder.
Currently there is no effective treatment for PSP, but some symptoms can be managed with medication or other interventions.
For more info: Progressive Supranuclear Palsy (PSP)
Multiple system atrophy (MSA) causes movement symptoms and affects the network of nerves — the autonomic nervous system — that controls blood pressure, digestion and other involuntary processes.
Symptoms of MSA include:
- Slowness, stiffness, and walking and balance problems
- Clumsiness and incoordination
- Slurred speech
- Low blood pressure, constipation and bladder problems
- Difficulty controlling emotions (laughing or crying at inappropriate times)
- Acting out dreams (REM sleep behavior disorder)
- Breathing problems, especially at night
The exact cause of MSA is not yet known. Lumps of the protein alpha-synuclein are seen in brain cells, in the support (glial) cells. Researchers are investigating these clumps to find out more about the disease and how to slow or stop it.
For more info: Multiple System Atrophy (MSA)
Corticobasal degeneration (CBD) causes movement, memory and thinking (cognitive), and behavioral symptoms. Movement symptoms typically start in one hand, arm or leg and later may involve other parts of the body.
In CBD, a protein called tau builds up in certain brain cells. Exactly why this protein accumulates and cells die isn't understood, but researchers are examining these mechanisms to understand the disease and find ways to target it.
Symptoms of CBD include:
- Slowness and stiffness
- Dystonia (muscle contractions causing abnormal postures)
- Myoclonus (rapid muscle jerks)
- Difficulty paying attention or concentrating, or other cognitive changes
- Language problems; trouble finding words or speaking in full sentences
- Behavioral changes, such as acting or speaking crudely
When the arm is involved, a person may be unable to control it, even though they know what they want to do and have the muscle strength to do so. For example, they may have trouble combing their hair or turning a key in a lock. Sometimes the arm may even move on its own; this is called "alien limb syndrome." CBD also may eventually lead to walking and balance problems.
For more info: Corticobasal Degeneration (CBD)