What is progressive supranuclear palsy?
Progressive supranuclear palsy (PSP) is a rare and progressive condition in which increasing numbers of brain cells become damaged over time. This is known as neurodegeneration.
The causes of PSP are unknown, although current research suggests that it is caused by a combination of environmental and genetic factors. Most cases of PSP first develop in people who are 60-65 years of age, although the condition has been diagnosed in people as young as 40.
What are the symptoms of PSP?
As PSP is a progressive condition, the initial symptoms will become more severe over time, and new symptoms can develop. The rate at which the symptoms of PSP progress can vary widely from person to person but early symptoms can include:
- progressive problems with balance and mobility
- changes in behaviour, such as irritability or apathy (lack of interest)
- an inability to control eye and eyelid movement, including focusing on specific objects or looking down at something (dystonia)
Later symptoms can include:
- increasing difficulties with speaking and swallowing (dysphagia)
- changes in thought, such as becoming increasingly forgetful or having difficulty concentrating
Although PSP itself is not life-threatening, it can lead to serious complications. One of the common complications of PSP is difficulty swallowing (dysphagia), leading to choking or inhaling food or liquid into the airways (aspiration). Aspiration can develop into pneumonia.
Good care and assistance can help people with PSP to have better quality of life and more independence.
How common is PSP?
It used to be thought that PSP was a very rare condition, but research has found that, while PSP is rare, it is much more widespread than previously thought. A recent study estimated that five new cases of PSP are diagnosed each year in every 100,000 people who are over 50 years of age.
However, this figure may be higher because many cases may have been misdiagnosed. PSP is often misdiagnosed as Parkinson’s disease, which shares some of the same symptoms. Read more about diagnosing PSP.
Although research into PSP continues, there is currently no cure for the condition. Treatment focuses on relieving symptoms while trying to ensure that someone with PSP has the best possible quality of life.
Treatment for PSP is provided by a team of health and social care professionals working together, as a person may be affected in many different ways. Specific symptoms of PSP might be treated with:
Progressive supranuclear palsy symptoms
As the name suggests, progressive supranuclear palsy (PSP) is a progressive condition. This means that the symptoms often develop gradually.
This makes it easy to mistake the symptoms of PSP for the symptoms of other, more common conditions.
The symptoms gradually become more severe over time, although only a few people will experience all the symptoms listed below. Individual symptoms can also vary in severity from person to person.
Initial symptoms of PSP may include:
- sudden loss of balance when walking that usually results in repeated falls, often backwards
- muscle stiffness, particularly in the neck
- changes in personality such as irritability, apathy (lack of interest) and sudden mood swings
- changes in behaviour such as recklessness and poor judgement
- a dislike of bright lights (photophobia)
- difficulty controlling the muscles of the eyes, particularly problems with looking up and down (this is the supranuclear palsy that gives the condition its name)
- blurred or double vision
Over time, the initial symptoms of PSP will become more severe and new symptoms will develop. The loss of balance can become so severe that walking becomes impossible and a wheelchair will eventually be required. People may develop slow, quiet or slurred speech with some swallowing problems.
Controlling the eye muscles will become more difficult, increasing the risk of falls and making everyday tasks, such as reading or eating, more problematic.
Some people with PSP will also experience problems controlling their eyelids, including:
- reduced blinking reflex, which can cause the eyes to dry out and become irritated
- involuntary closing of the eyes, which can last from several seconds to hours
- difficulties opening the eyelids
As PSP progresses to an advanced stage, people with the condition may begin to experience increasing difficulties controlling the muscles of their mouth, throat and tongue.
Speech may become increasingly slow and slurred, making it harder to understand. There may also be some problems with thinking, concentration and word finding, although severe dementia is rare.
The loss of control of the throat muscles leads to difficulties swallowing (dysphagia). At some point, many people with PSP will need to consider using a feeding tube.
Many people with PSP also develop problems with their bowel and bladder functions. Constipation and difficulties in passing urine are common, as is the need to pass urine several times during the night.
Due to dysphagia, many people with PSP will experience repeated chest infections that are caused by fluids or small particles of food inadvertently passing into their lungs. This is known as aspiration pneumonia and it is a leading cause of death in cases of PSP. Read more about the complications of PSP.
Progressive supranuclear palsy causes
Progressive supranuclear palsy (PSP) is caused by damage to brain cells in the parts of the brain that help control movement, balance, vision and speech.
Some of the brain cells are damaged by clumps of a protein called tau. Tau occurs naturally in the brain, but people with PSP have much higher levels.
Tau is normally broken down in the brain. In PSP the tau changes slightly, allowing clumps to build up and damage cells.
PSP has similar symptoms to another neurodegenerative condition called corticobasal degeneration (CBD), although the pattern of brain damage is slightly different. It may be the case that both PSP and CBD are in fact two related syndromes that are the result of the same underlying cause (or causes).
It is not known what leads to the overproduction of the tau protein and the resulting death of brain cells. Recent research has indicated that genetic factors can make someone more likely to develop PSP, but cases of PSP are nearly always a one-off in a family. The risk to other members of the family, including children or siblings of someone with PSP, is extremely low.
It is important to note that there is no evidence that PSP can be passed down from a parent to their child, and most experts think that it is unlikely that PSP is an inherited condition.
Further research is ongoing to identify what other factors may trigger PSP. Suggested environmental triggers include:
- an, as yet, unidentified virus or other type of infection, which may slowly infect the brain over the course of many years
- an unidentified neurotoxin (a poison that damages brain and nerve cells) that may be present in the environment
Progressive supranuclear palsy diagnosis
There is no single test to diagnose progressive supranuclear palsy (PSP). Instead, the diagnosis is based on the type and pattern of your symptoms, while other conditions that can cause similar symptoms are ruled out.
The diagnosis must be made or confirmed by a consultant with expertise in PSP (usually this will be a neurologist).
If you have symptoms of PSP that suggest there is something wrong with your brain it is likely that you will be referred for a scan.
Brain imaging scans may include:
- magnetic resonance imaging (MRI) scan - where strong fluctuating magnetic fields are used to produce a detailed image of the inside of the brain
- positive emission tomography (PET) scan - similar to an MRI scan, a PET scan has the added advantage of being able to assess how different parts of the brain are functioning
They can also detect abnormal changes to the brain that are consistent with a diagnosis of PSP, such as shrinkage in the cortex and basal ganglia.
Ruling out Parkinson’s disease
You may be prescribed a medication called levodopa which can help to determine whether your symptoms are caused by PSP or Parkinson’s disease. People with Parkinson’s disease usually experience a marked improvement in their symptoms after taking levodopa.
However, this is not the case for people with PSP as levodopa usually only has a limited beneficial effect in one in three people with the condition.
It is also likely that you will be referred to a neurologist (nerve and brain specialist) and possibly also a psychologist for what is known as neuropsychological testing.
This involves having a series of tests that are designed to evaluate the full extent of your symptoms and their impact on your mental abilities.
The tests will look at abilities such as:
- ability to understand language
- the ability to process visual information, such as words and pictures
Most people with PSP have a distinct pattern in terms of their mental abilities, including poor concentration, a low attention span and problems with spoken language and processing visual information. Their memory of previously learned facts is usually unaffected.
Once other possible causes of your symptoms have been ruled out, a confident diagnosis of PSP can usually be made.
Being told that you have PSP can be an emotionally devastating experience, and the news can often be difficult to take in. Therefore, at this time, it is important that you have the support of your family and care team who will be able to help you to come to terms with the diagnosis.
As your symptoms progress you will require full-time care and equipment, such as a wheelchair, to help with activities.
Progressive supranuclear palsy treatment
Progressive supranuclear palsy (PSP) can affect many different aspects of your life and health. Because of this, treatment is given by a team of health and social care professionals who work together. This type of team is known as a multidisciplinary team (MDT) because it contains experts from many different healthcare disciplines. The team will include:
- a neurologist - a specialist in treating conditions that affect the nervous system
- a physiotherapist - a therapist who helps people to improve their co-ordination and range of movement
- a speech and language therapist
- an occupational therapist - a therapist who helps people to improve the skills and abilities that they need for daily activities, such as washing or dressing
- a psychologist
- a social worker - who will be able to advise you about the support available from social services
- an ophthalmologist or orthoptist - specialists in treating eye conditions
- a palliative care specialist - a healthcare professional who specialises in treating people with terminal conditions
- a specialist neurology nurse - who might be your first point of contact with the rest of the team
While there is no cure for PSP, there are medications that may help to control symptoms. They include:
- [levodopa], amantadine and other medications used for Parkinson's disease, which can improve balance and stiffness in around 1 in 3 people
- antidepressants, which are used to help with depression, which can come with PSP, but these may only be effective on a short-term basis
- amitriptylline, which, in low doses, is sometimes used for pain and sleep problems in PSP
Also, people with PSP can be more sensitive to side effects of other medications, and your specialist may suggest stopping them.
A physiotherapist can advise you about how to make the most of your remaining mobility by using exercise. Regular exercise can help to strengthen your muscles, improve your posture and prevent stiffening of your joints.
Your physiotherapist will also be able to advise you about any aids that could be of benefit to you, such as a walking frame, or shoes that have been specially designed to reduce your risk of slipping and falling.
A physiotherapist will also be able to teach you breathing exercises that you can use when you eat to reduce your risk of developing aspiration pneumonia (a chest infection that is caused by small particles of food falling into your lungs). Read more about the complications of PSP.
Speech and language therapist (SLT)
A speech and language therapist (SLT) can help to improve your speech and swallowing problems (dysphagia). They can also teach you a number of techniques to make the most of your speech function by making your voice as clear as possible.
As PSP progresses, you may need some sort of assistive technology to help you to communicate. A range of communication aids are available, and your SLT will be able to advise you about the devices that will be most suitable for you.
Your SLT may be able to teach you exercises that can stimulate the nerves that are used to trigger your swallowing reflex, as well as strengthening the muscles that are used during swallowing.
There are also physical techniques that can be used to make swallowing easier. For example, some people find that moving their chin forward while swallowing helps to prevent any food from entering their airways.
As the symptoms of your dysphagia become more severe, you will require additional treatment to compensate for your swallowing difficulties (see below).
Diet and severe dysphagia
You may be referred to a dietitian, who will advise you about making changes to your diet, such as including food and liquids that are easier to swallow while ensuring that you receive a healthy, balanced diet.
For example, mashed potatoes are a good source of carbohydrates, while scrambled eggs and cheese are high in protein and calcium.
Feeding tubes may be recommended in severe cases of dysphagia that increase your risk of developing malnutrition or dehydration. You should discuss the pros and cons of feeding tubes with your family and care team, preferably when your symptoms of dysphagia are at an early stage.
There are two types of feeding tubes:
- nasogastric tube - a temporary tube that is passed down your nose and into your stomach
- percutaneous endoscopic gastrostomy (PEG) tube - a tube that is surgically implanted directly into your stomach, which passes through a small incision on the surface of your stomach or abdomen
Nasogastric tubes are designed for short-term use and last for 10-28 days before they need to be replaced. PEG tubes are designed for long-term use.
Read more information about how dysphagia is treated.
An occupational therapist (OT) can provide advice about the best ways of increasing your safety and preventing trips and falls during your day-to-day activities.
For example, many people with PSP benefit from having bars placed along the sides of their bath to make it easier to get in and out.
The OT will also be able to spot potential hazards in your home that could lead to a fall, such as poor lighting, badly secured rugs and crowded walkways and corridors.
Treating eye problems
If you are having problems controlling your eyelids, botulinum toxin (BTA) can be used to help relax the muscles of your eyelids. BTA works by blocking the signals from the brain to the affected muscles. The effects of the injection normally last for up to three months.
If you are experiencing dryness of your eyes due to reduced blinking, eyedrops can be used to lubricate them and reduce irritation.
Glasses that contain specially designed lenses can help some people who are having problems looking down. Wearing wraparound, dark glasses can help those who are vulnerable to bright light.
Palliative care can be offered at any stage of PSP alongside other treatments.
It aims to relieve pain and other distressing symptoms while providing psychological, social and spiritual support.
Palliative care can be received:
- in a hospice
- at home or in a residential home
- as a day patient in a hospice
- in a hospital
Many people with PSP draw up an advance decision. An advance decision is where you make your treatment preferences known in advance in case you cannot communicate your decisions later because you are too ill.
Issues covered by an advance decision include:
- whether you want to be treated at home, in a hospice or in a hospital once you reach the final stages of PSP
- what type of painkillers you would be willing to take
- whether you would be willing to use a feeding tube if you were no longer able to swallow food and liquid
- whether you are willing to donate any of your organs once you die (the brains of people with PSP are particularly useful for research purposes)
- if you experience respiratory failure (loss of lung function) due to aspiration pneumonia, whether you would be willing to be resuscitated by artificial means, for example by having a breathing tube inserted into your neck
You cannot request anything illegal in your advance decision, such as assisted suicide.
Your care team will be able to provide you with more information and advice about advance decisions.
Complications of progressive supranuclear palsy
Progressive supranuclear palsy (PSP) can have serious complications including choking and pneumonia caused by problems with swallowing (dysphagia), or injuries caused by falls.
Falls are a common complication of PSP due to the associated problems with balance and vision. They can be very serious as people often fall backwards and without warning.
In the most serious cases falls can cause fractures or head injuries, which can be life-threatening.
The risk of a fall can often be reduced through good care and assistance. Treatment includes the use of walking aids, methods to improve balance and eyesight problems, and identifying potential hazards in the home. Read more about how PSP is treated.
Aspiration pneumonia is one of the most potentially serious complications of progressive supranuclear palsy (PSP). Aspiration pneumonia is a lung infection that is triggered when fluids or small pieces of food enter your lungs.
People with PSP are particularly vulnerable to aspiration pneumonia because their impaired swallowing reflexes mean that their larynx (voice box) does not close during swallowing, leaving their lungs unprotected.
The symptoms of aspiration pneumonia include:
- high temperature (fever) above 38°C (100.4°F)
- chest pain
- shortness of breath
- blue skin (cyanosis) - due to a lack of oxygen
You may also have a cough which sometimes produces foul-smelling phlegm and may contain traces of blood and pus.
Contact your care team immediately if you are being treated for PSP and you develop the above symptoms. If this is not possible, you should contact your local out-of-hours service.
The symptoms of aspiration pneumonia can range from mild to severe. Severe cases will require hospital admission and treatment with intravenous antibiotics (antibiotics that are given through a vein).
In particularly vulnerable or frail people, there is a risk that the infection could lead to their lungs becoming filled with fluid, preventing them from working properly. This is known as acute respiratory distress syndrome (ARDS).
Unfortunately, as most people with advanced PSP are vulnerable and frail, repeated episodes of aspiration pneumonia can be fatal.