Progressive Supranuclear Palsy

What Is Progressive Supranuclear Palsy?

Progressive supranuclear palsy (PSP) is a rare brain condition that affects body movements such as walking, balance, and eye function. PSP is caused by damage to nerve cells in areas of the brain that control and coordinate movement. This damage results in gradual weakness or paralysis of the muscles controlled by this region, including eye muscles.

What Causes Progressive Supranuclear Palsy?

People with progressive supranuclear palsy have higher amounts of a protein called tau in the brain. Higher levels of tau cause nerve cells to die. This protein also occurs in other conditions characterized by nerve damage in the brain, such as Alzheimer’s disease. Researchers aren’t sure what causes higher tau levels.

Progressive Supranuclear Palsy Symptoms

Progressive supranuclear palsy is one of several atypical parkinsonism disorders. Early symptoms of PSP are often mistaken for Parkinson’s disease, but symptoms of PSP progress more quickly. Most symptoms affect control of muscle movement or motor control, while other non-motor symptoms may affect mood or behavior.

Motor symptoms of PSP may include:

• Stiff or slow movements in the limbs, trunk (axial rigidity), or neck

• Problems with walking, balance, clumsiness, and frequent falls

• Tendency to lean or lunge forward to avoid falling backward

• Problems with moving the eyes, looking down, keeping eyes open, and sensitivity to bright light

• Changes in facial expressions/deeply lined face

• Tremors or muscle spasms (especially in the jaw or face)

• Difficulty speaking/swallowing

Non-motor symptoms of PSP may include:

• Behavioral changes, including impulsivity or poor judgment

• Dizziness

• Dementia (mild-to-moderate memory loss, difficulty with reasoning, making decisions, and solving problems)

• Personality or mood changes (depression, anxiety, irritability, laughing or crying without reason)

• Sensitivity to bright light

• Sleep disturbances (insomnia, rapid eye movement sleep behavior disorder)

What Are the Stages of Progressive Supranuclear Palsy?

Doctors track the progression of PSP in four stages:

• Early stage usually occurs within the first year after disease onset. These symptoms may look like normal changes associated with aging. At this stage, people may have trouble with balance and walking. Visual problems may impact the ability to read. Voice changes start to occur with reduced speaking volume. Some people experience mood and behavior changes, including apathy, anxiety, and decreased interaction with other people.

• Mid-stage PSP usually occurs between the second and third years with the condition. People with PSP often need walking aids and experience more vision problems. Speaking and swallowing may become more difficult.

• Advanced stage PSP usually occurs between years three through six. People with PSP have significant problems with walking, muscle stiffness, and pain, often requiring a wheelchair for mobility. They depend on others for most or all care aspects. Vision, speech, and swallowing are significantly impaired. The risks for inhaling food (aspiration) and developing pneumonia are very high.

• End-of-life PSP typically spans six to eight weeks. Reduced consciousness and marked deterioration in the ability to eat or drink resulting in rapid weight loss occur during this stage. A fall, major fracture, or infection may also occur during this period.

Diagnosing PSP

Progressive supranuclear palsy is difficult to diagnose, especially in early stages. No standard laboratory tests or imaging studies can confirm this brain condition.

Doctors typically rule out all other possibilities in order to diagnose PSP. Early PSP symptoms mimic those of Parkinson’s disease or other nerve conditions, but these symptoms often do not respond well to standard Parkinson’s disease treatments.