Progressive supranuclear palsy (PSP) is a rare, degenerative neurological condition. It usually starts in middle age and can cause symptoms similar to those of Parkinson’s disease.

PSP can cause Parkinson’s-like symptoms, including issues with balance and muscle stiffness. This similarity can delay a correct diagnosis of PSP.

There is currently no cure for PSP. However, working with a multidisciplinary healthcare team can help someone cope with the wide range of possible symptoms they may experience.

Read on to learn about PSP, its symptoms, risk factors, diagnosis, and more.

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PSP affects the basal ganglia, cerebellum, and brainstem. As it advances, it can also affect the brain’s frontal and temporal lobes. It occurs due to damage to cells in parts of the brain that control movement and thinking.

The rare, degenerative neurological condition affects 5–6 in every 100,000 people and can cause problems with:

  • body movement
  • walking
  • balance
  • eye movement

It usually starts in late middle age and gradually worsens with time. People who develop the condition are generally over the age of 40, but the symptoms usually start at the age of 60 years.

During the early stages of the disease, PSP symptoms can mimic those of other conditions: commonly Parkinson’s disease and dementia. PSP typically causes cognitive changes that are more severe and start earlier than Parkinson’s symptoms, so doctors can easily mistake it for dementia.

The main signs of PSP include:

  • balance and mobility problems, including frequent falls
  • behavior changes — for instance, becoming irritable or apathetic
  • muscle stiffness
  • limitations in eye movements
  • slow, quiet, or slurred speech
  • dysphagia, or difficulty swallowing
  • cognitive impairment and memory problems

The symptoms of PSP gradually worsen over time. For instance, in the early stages, a person may suddenly lose balance while walking and fall over.

The mid-stages of the condition may cause them to have difficulty swallowing and moving their eyes in certain directions. In the latter stages, they may experience incontinence and require a feeding tube.

However, it is important to note that the rate of progression can vary from person to person.

The development of PSP has links to an excessive buildup of tau, a naturally occurring protein in the brain.

Tau usually breaks down before it reaches problematically high levels. However, people with PSP are unable to break it down typically, so the substance can accumulate and form tangles, or clumps, with neurons. These are the information messenger cells in the brain.

The amount and exact location of these clumps vary.

Although experts do not know the precise reason why PSP occurs, they know there is a link between the condition and certain genetic mutations. However, individuals do not inherit these mutations, so the condition likely does not run in families.

There is no definitive test for PSP, so doctors base the diagnosis on the pattern of a person’s symptoms. However, the wide range of possible PSP symptoms can make diagnosing the condition difficult, so it may take some time to reach a diagnosis.

Testing

Part of a doctor’s assessment involves ruling out other similar conditions such as Parkinson’s disease. A healthcare professional will also carry out a physical examination, as those with PSP would not have muscle weakness relating to the disease. They can use this exam to rule out a stroke, nutritional deficiency, or brain tumor.

Other tests a doctor may order include:

  • brain scans
  • cognitive tests of memory and thinking skills
  • mental focus tests
  • language comprehension tests

It is not uncommon for people with PSP to receive a delayed diagnosis. This delay can be due to a person putting off consulting a doctor because they do not see these early symptoms as anything to worry about.

The delay can also happen because doctors often misdiagnose PSP as Parkinson’s disease, Alzheimer’s disease, dementia, depression, or another neurodegenerative disorder.

ICD-10

In October 2015, PSP received a specific diagnostic code in the International Statistical Classification of Diseases, known as ICD-10.

ICD facilitates the reporting and coding of diseases and death worldwide, providing researchers with important insight into the extent, causes, and consequences of certain conditions. This new code may help healthcare professionals correctly diagnose PSP sooner.

Doctors do not have a cure for PSP, so treatments will focus on managing a person’s symptoms.

Some people may benefit from taking medicines typically for Parkinson’s disease in the early stages of PSP. Additionally, doctors may prescribe other medications depending on a person’s symptoms. For instance, these may include drugs to help with sleep problems.

This can involve a person taking a short course of a medication called levodopa. This can determine whether their symptoms represent PSP or Parkinson’s disease.

A team of healthcare professionals with a range of skills works together to treat someone with PSP.

For instance, a physical therapist can provide a safe exercise plan to help a person make the most of their mobility. Additionally, a speech and language therapist can help someone who experiences difficulty with talking or swallowing.

An occupational therapist can also suggest home modifications, such as grab handles beside the bathtub, to reduce a person’s risk of trips or falls.

People who develop eye movement problems due to PSP may benefit from Botox injections to help relax the muscles. Some people may need additional eye lubrication due to reduced blinking, while others can benefit from special glasses to help them look downward or to cope with bright light.

Pneumonia is the most common cause of death in people with PSP. However, with a supportive healthcare team and appropriate symptom management, a person can expect to live well into their 70s or longer.

Additionally, while recent clinical trials did not find an effective neuroprotective treatment for PSP, they led to better-designed ongoing trials.

If a person shows any signs or symptoms of PSP, such as trouble with balance, changes in mood or memory, or difficulty looking up or down, they should contact a doctor as soon as possible.

While there is no cure for PSP, proper symptom management from a multidisciplinary healthcare team can make living with the condition more comfortable. The sooner someone receives a diagnosis, the sooner they can receive the support they need.

PSP is a rare degenerative neurological condition that can cause a wide range of symptoms. In the early stages, the disease can mimic Parkinson’s disease and other conditions, so doctors often misdiagnose PSP.

Once a person receives a correct diagnosis, treatment focuses on managing their unique set of symptoms.

This may include medications, physical therapy, speech therapy, and nutrition advice. While living with the condition can bring various challenging symptoms for a person to deal with, it is possible to maintain a high quality of life with the right support.