What is progressive supranuclear palsy?

Progressive supranuclear palsy (PSP) is a rare neurological disorder that affects body movements, walking and balance, and eye movements. PSP is caused by damage to nerve cells in areas of the brain that control thinking and body movements. It is one of a family of neurological conditions called atypical parkinsonism and belongs to the category of frontotemporal disorders.

PSP is different from Parkinson's disease, although some of their symptoms are similar. PSP typically begins in a person’s mid- to late-60s, later than when Parkinson’s disease symptoms typically develop. The disease usually worsens rapidly and most people with PSP develop severe disability within three to five years of symptom onset. PSP can lead to serious complications such as pneumonia, choking, or head injuries from falls.
Symptoms of Progressive Supranuclear Palsy

PSP affects a person’s movements, and can lead to loss of balance, difficulty walking or swallowing, slurred speech, problems with eye movements. PSP can also affect a person’s mood, behavior, and thinking. The most frequent first symptom of PSP is a loss of balance while walking which can lead to abrupt and unexplained falls. People with PSP may also have stiffness and slow movement.

As the disease progresses, most people develop eye problems. Eye and vision symptoms may include:

Slow eye movements
Trouble looking up or down
Trouble controlling eyelids, involuntary closing of the eyes, decreased blinking, or difficulty opening the eyes
Tendency to move the head rather than just the eyes to look in different directions
People with PSP and their loved ones may notice changes in mood or behavior. These may include:

There are several key differences between PSP and Parkinson's:

• People with PSP tend to lean backwards and extend their neck. The unexplained falls that accompany PSP usually arise from falling backward. This is termed “axial rigidity.” People with Parkinson's tend to bend forward rather than backward.
• Problems with speech and swallowing are much more common and severe in PSP than in Parkinson's and usually show up earlier in the disease.
• People with PSP develop unique eye movement problems with looking up and down.
• Tremor is rare in PSP but very common in individuals with Parkinson's.
• Individuals with Parkinson’s disease often show great benefit from levodopa therapy, while people with PSP have minimal or no response.
• A signature of PSP is the accumulation in affected brain cells of a protein known as tau, whereas in Parkinson's, a different protein called alpha-synuclein accumulates in diseased brain cells.

Who is more likely to get PSP?
The exact cause of PSP is unknown, but research suggests that it involves progressive damage to cells in a few specific areas in the brain, mainly in the brain stem. The death of brain cells in one of these areas, the substantia nigra, accounts in part for the motor symptoms that PSP and Parkinson's have in common.