Progressive Supranuclear Palsy

Progressive Supranuclear Palsy Overview

Progressive supranuclear palsy (PSP) is a rare degenerative disease of the brain. The disease impairs movements and balance. Many people with PSP also experience changes in mood, behavior, and personality. A decline in cognitive mental processes, such as thinking, memory, attention, and speech, is not uncommon. When these mental changes are severe enough to interfere with everyday activities, they are called dementia.

The name progressive supranuclear palsy seems like a mouthful, but it accurately describes the disease. PSP is progressive, meaning that it gets worse over time. The disease affects the part of the brain above the nuclei (“supranuclear”), which are pea-sized structures in the part of the nervous system that controls eye movements. Palsy means weakness, and it is this characteristic weakness in eye movements for which the disease is named. PSP is sometimes called Steele-Richardson-Olszewski syndrome, after the 3 scientists who first described it in 1963.

About 20,000 people in the United States have PSP. The disease usually develops in people aged 60 years or older. Symptoms typically become noticeable in the early 60s, although the disease sometimes affects people in their 40s or 50s. PSP is slightly more common in men than in women.

Because PSP mainly affects older people and has somewhat similar symptoms, it is often mistaken for Parkinson disease, a much more common movement disorder. The distinction is important, because treatments that help many people with Parkinson disease do not help those with PSP. Unfortunately, we do not yet have an effective treatment for PSP.

Progressive Supranuclear Palsy Causes

The cause of PSP is not known. In a few rare cases, the disease runs in families, but it usually does not. No links have been uncovered between PSP and surroundings, occupation, or lifestyle. Research is focusing on genes that may predispose a person to developing the disease.

Progressive Supranuclear Palsy Symptoms

The symptoms of PSP usually appear very slowly. Many people experience a prolonged phase of symptoms such as fatigue (feeling tired), headaches, joint pains, dizziness, and depression. Gradually, the following more specific symptoms appear:

• Unexplained balance problems
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• Stiff or awkward steps while walking
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• Very slow movements
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• Frequent falls, clumsiness
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• Visual problems - Blurry or double vision, problems controlling eye movements (inability to maintain eye contact), light sensitivity
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• Behavior or personality changes - Irritation, grouchiness
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• Memory loss, forgetfulness
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• Apathy (indifference)
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• Slowed thinking, reasoning, planning
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• Inappropriate laughing or crying
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• Angry or aggressive outbursts
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• Slurred speech
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• Swallowing problems - Solids and liquids
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• Mask-like facial expression (no expression)
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• Muscle spasms
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• Inability to hold urine (incontinence) - Late stages only

No one has all these symptoms. The pattern of symptoms varies widely from person to person. Often, friends and family members are more aware of these changes than the affected person.

Most patients with PSP display the characteristic findings of slowness of movement, stiffness, balance difficulty, and eye movement problems. The classic eye movement problem is an inability to voluntarily move the eyes downward, although this problem may take time to develop. Ultimately, all voluntary eye movements may be lost.

Generally, the cognitive and behavioral symptoms are mild and less severe than in other types of dementia, such as Alzheimer disease and stroke-related dementia. These symptoms are more likely to occur in later stages of the disease.