Parkinson's Disease: Classification

Topic Overview

Parkinson's disease and parkinsonism

Parkinson's disease is named for Dr. James Parkinson, who in 1817 first described the features of this illness. Features of Parkinson's disease include tremor, slow movement (bradykinesia), and rigid muscles (rigidity). People with parkinsonism may have Parkinson's disease or another illness with similar symptoms.

Other conditions and diseases that cause parkinsonism may also cause symptoms that are not seen with Parkinson's disease. These conditions may be treated differently than Parkinson's disease. Unlike Parkinson's, some conditions that cause parkinsonism are reversible.

• Parkinson's-plus syndromes are a group of disorders characterized by the degeneration of nerve cells in different parts of the brain. They include progressive supranuclear palsy (PSP), corticobasal degeneration (CBD), and multiple system atrophy (MSA), among others. Parkinson's-plus syndromes have parkinsonian features as well as features that are not associated with Parkinson's disease. These syndromes usually respond poorly to levodopa or dopamine agonists.
• Secondary or symptomatic parkinsonism describes the syndrome of parkinsonism when it occurs as the result of an identifiable cause. For example, certain medicines, brain tumors, strokes, infections (such as encephalitis), and toxins (such as carbon monoxide or manganese) can cause secondary parkinsonism.

Stages of Parkinson's disease

It may be helpful for people with Parkinson's disease and their families to be familiar with some of the ways the disease is described. Experts describe symptoms and stages of the disease differently.

Parkinson's disease sometimes is described as early, moderate, or advanced.

• Early disease describes the stage when a person has a mild tremor or stiffness but is able to continue work or other normal daily activities. This often refers to a person who has been newly diagnosed with Parkinson's disease.
• Moderate disease describes the stage when a person begins to experience limited movement. A person with moderate Parkinson's disease may have a mild to moderate tremor with slow movement.
• Advanced disease describes the stage when a person is significantly limited in his or her activity, despite treatment. Daily changes in symptoms, medicine side effects that limit treatment, and loss of independence in activities of daily living are common. A person with advanced Parkinson's disease may have significant problems with posture, movement, and speech.

Parkinson's disease may also be described by five stages:

• Stage I: Symptoms affect only one side of the body.
• Stage II: Both sides of the body are affected, but posture remains normal.
• Stage III: Both sides of the body are affected, and there is mild imbalance during standing or walking. But the person remains independent.
• Stage IV: Both sides of the body are affected, and there is disabling instability while standing or walking. The person in this stage requires substantial help.
• Stage V: Severe, fully developed disease is present. The person is restricted to a bed or chair.

Medical professionals may refer to this scale when discussing the disease and decisions about treatment.