Progressive supranuclear palsy (PSP)

Progressive supranuclear palsy (PSP) is a rare condition that impacts various motor functions such as walking, balance, swallowing and eye movements. It’s a progressive disease that stems from cell damage in specific brain areas responsible for controlling movement, coordination and thinking.

Also known as Steele-Richardson-Olszewski syndrome, PSP may result in severe complications such as pneumonia and difficulty swallowing.

What is PSP?

Progressive supranuclear palsy is characterized by two key features – abnormal protein aggression and neurodegeneration in the brain.

The hallmark of PSP is the abnormal accumulation of tau proteins within certain brain cells. Tau proteins normally help stabilize the structure of nerve cells, but in PSP, they form tangled clumps, disrupting cell function and leading to cell death.

PSP primarily affects specific areas of the brain, including the brainstem and basal ganglia. These regions play critical roles in movement, balance, coordination and eye movement control. The degeneration of nerve cells in these areas contributes to the characteristic motor and cognitive symptoms found in those with PSP.

The four stages of PSP

PSP typically has four stages to characterize how far along the disease has progressed. Each stage has its own unique symptoms. These stages include:

• Early stage: Symptoms may look like normal signs of aging, such as trouble walking or vision problems. Some people develop anxiety and decreased desire to interact with others.
• Mid-stage: At this stage, you may need walking aids and vision problems may worsen. Trouble swallowing and speaking are also common.
• Advanced stage: Motor abilities worsen in this stage. You may require a wheelchair and will become more dependent on others for most or all care. Vision and speech are significantly impaired as well. The risks for inhaling food (aspiration) and developing pneumonia are very high.
• End of life: You may likely not be able to eat or drink on your own. The risk of falling, major fracture or an infection is high.

PSP symptoms as disease progresses

As progressive supranuclear palsy moves into the middle and late stages, symptoms often mimic those of other diseases such as Parkinson’s disease, dementia and multiple system atrophy (MSA).

Later stage symptoms of PSP might include:

• Stiffness, particularly in the neck and clumsy movements
• Increased frequency of falling, particularly backward
• Speech slowness or slurring
• Difficulty swallowing, potentially leading to gagging or choking
• Sensitivity to bright light
• Sleep disturbances
• Decreased interest in previously enjoyable activities
• Impulsive behavior, unexplained laughter or crying
• Impaired reasoning, problem-solving and decision-making abilities
• Onset of depression and anxiety
• A fixed or startled facial expression due to rigid facial muscles
• Feelings of dizziness

What are the early symptoms of PSP?

Symptoms of progressive supranuclear palsy are often mild and may go unnoticed or be mistaken for other conditions.

Early symptoms may include subtle changes in balance, gait instability, difficulties with eye movements and cognitive changes such as mild executive dysfunction.

Some individuals may experience changes in mood or behavior during this stage.

As the disease progresses into later stages, symptoms become more pronounced and impact daily functioning. Gait and balance problems worsen, leading to an increased risk of falls.

What is the cause of PSP?

The exact cause of progressive supranuclear palsy remains unknown. However, symptoms stem from cell damage in specific brain regions.

Studies have revealed that individuals with PSP have an accumulation of tau proteins in their damaged brain cells. Similar tau protein clumps are also found in other brain disorders like Alzheimer's disease.

It’s possible for PSP to be passed down genetically, but that’s not always the case. Most individuals with this condition haven’t inherited it.

PSP diagnosis

Diagnosing progressive supranuclear palsy can pose challenges due to its resemblance to Parkinson's disease symptoms.

Your provider might consider PSP instead of Parkinson's disease if you:

• Don't have any tremors
• Fall frequently and cannot explain why
• Aren’t responding to Parkinson’s disease medications
• Struggle to move your eyes, especially down

Your provider may recommend an MRI or a PET scan to confirm a PSP diagnosis. An MRI helps discover any shrinking in the brain regions that are impacted by PSP. This imaging technique can also help rule out other conditions that mimic its symptoms.

A PET scan might be recommended to detect early brain changes not visible on an MRI.

Treating and managing PSP

With no cure, treatment is centered around making you comfortable and alleviating your symptoms. There are several treatments that help symptoms of progressive supranuclear palsy. These include:

• Parkinson's disease medications: These medications elevate levels of a brain chemical that’s crucial for smooth muscle movements. However, their effectiveness tends to be limited and temporary.
• Botox: Neurotoxin can be injected in tiny amounts into the muscles around the eyes, effectively blocking the chemical signals responsible for muscle contractions.
• Antidepressants: Some antidepressant medications may offer relief for symptoms like impulsive behavior.
• Therapies: Physical therapy, occupational therapy and speech therapy aim to enhance balance and may include facial exercises, the use of talking keyboards and gait and balance training, all of which can help manage various symptoms of progressive supranuclear palsy.
• Palliative care: Palliative care is provided in hospitals, clinics, nursing facilities or in your home. The goal of palliative care is to provide relief from the symptoms of a serious illness, regardless of the stage of the disease.

To minimize the effects of progressive supranuclear palsy, you can take certain steps at home such as using eye drops, walking with a walker and removing falling hazards.