Parkinsonism refers to symptoms of Parkinson disease (such as slow movements and tremors) that are caused by another condition.
Parkinsonism is caused by brain disorders, brain injuries, or certain drugs and toxins.
People with parkinsonism, like those with Parkinson disease, have tremors that occur when muscles are relaxed, stiff muscles, slow movements, and problems with balance and walking.
Doctors try to identify the cause of parkinsonism by asking about conditions known to cause it and by using brain imaging to look for a possible cause.
The cause is treated if possible, medications may be used to relieve symptoms, and general measures (such as simplifying daily tasks) may help people function better.
(See also Overview of Movement Disorders.)
Parkinsonism does not include Parkinson disease although the disorders included in parkinsonism resemble Parkinson disease in some ways. There are two main types of parkinsonism:
Secondary parkinsonism refers to a group of disorders that have a different cause from Parkinson disease.
Atypical parkinsonism refers to a group of degenerative disorders that have some different symptoms and different changes in the brain and that respond to treatment differently. People with these disorders have a worse prognosis.
Causes of Parkinsonism
The most common cause of parkinsonism is
Use of medications that block or interfere with dopamine’s action
Certain drugs and toxins interfere with or block the action of dopamine and other chemical messengers that help nerve cells communicate with each other (neurotransmitters). For example, antipsychotic medications, used to treat paranoia and schizophrenia, block dopamine’s action. Dopamine is a key neurotransmitter in the basal ganglia (collections of nerve cells located deep within the brain), which help smooth out muscle movements.
Various other conditions can cause parkinsonism:
Degenerative disorders, such as Alzheimer disease, multiple system atrophy, corticobasal ganglionic degeneration, frontotemporal dementia, and progressive supranuclear palsy
Viral encephalitis, including West Nile virus encephalitis and a rare brain inflammation that follows a flu-like infection
Structural brain disorders, such as brain tumors and strokes
Head injury, particularly the repeated injury that occurs in boxing (making a person punch-drunk)
Wilson disease (mainly in young people)
Certain spinocerebellar ataxias
Symptoms of Parkinsonism
Parkinsonism causes symptoms that are similar to those of Parkinson disease. They include
A tremor that occurs in one hand while the muscles are relaxed (a resting tremor)
Stiff muscles
Slow movements
Difficulty maintaining balance and walking
The disorders that cause parkinsonism may also cause other symptoms or variations of parkinsonian symptoms.
Some symptoms may indicate the cause is probably not Parkinson disease. They include
Prominent memory loss that occurs during the first year of the disorder (indicating dementia)
Symptoms of parkinsonism on only one side of the body (often due to certain brain tumors or corticobasal ganglionic degeneration)
Low blood pressure, difficulty swallowing, constipation, and urinary problems (sometimes due to multiple system atrophy)
Falls and confinement to a wheelchair within the first months or years of a disorder
Abnormalities in eye movements
Hallucinations and visual-spatial problems (such as difficulty finding rooms at home or parking a car) that develop early in the disorder
Inability to express or understand spoken or written language (aphasia), inability to do simple skilled tasks (apraxia), and inability to associate objects with their usual role or function (agnosia) due to corticobasal ganglionic degeneration
In corticobasal ganglionic degeneration, the cerebral cortex (the part of the brain that contains most of the nerve cells) and the basal ganglia deteriorate progressively. Symptoms usually begin after age 60 (see figure Locating the Basal Ganglia).
People with corticobasal ganglionic degeneration have stiff muscles that affect one side of the body more than the other. As the disorder progresses, moving their limbs becomes increasingly difficult. Coordination and balance are poor, muscle twitch, and swallowing becomes difficult. Thinking is impaired, and people have difficulty finding, saying, and understanding words. Many people lose control of one hand (on the more affected side)—called alien hand syndrome. The hand may move on its own. For example, it may spontaneously open or make a fist.
Diagnosis of Parkinsonism
A doctor's evaluation
Usually brain imaging
Doctors ask about previous disorders, exposure to toxins, and use of drugs that could cause parkinsonism.
Brain imaging, such as computed tomography (CT) or magnetic resonance imaging (MRI), is usually done to look for a structural disorder that may be causing the symptoms.
levodopa results in clear improvement, Parkinson disease is the likely cause.
Treatment of Parkinsonism
Treatment of the cause if possible
Sometimes medications to help relieve symptoms
General measures, such as staying as active as possible
The cause of parkinsonism is corrected or treated if possible. If a drug is the cause, stopping the drug may cure the disorder. Symptoms may lessen or disappear if the disorder causing them can be treated.
The medications used to treat Parkinson disease (such as ) are often not effective in people with parkinsonism but can sometimes result in temporary improvement.
The same general measures used to help people with Parkinson disease maintain mobility and independence are useful. For example, people should
Remain as active as possible
Simplify daily tasks
Use assistive devices as needed
Take measures to make the home safe (such as removing throw rugs to prevent tripping)
Physical therapists and occupational therapists can help people implement these measures.
Good nutrition is also important.
