It’s also common for someone with CBD to experience personality changes, such as becoming apathetic, irritable, agitated or anxious.
As CBD reaches an advanced stage, muscle stiffness will continue to get worse. People with the condition may lose the ability to move 1 or more limbs. Some people are unable to walk and need a wheelchair or assistance to transfer (such as help getting into and out of bed).
The condition tends to develop gradually, which means it can be mistaken for another condition at first – such as Parkinson’s disease, dementia or a stroke.
Problems affecting the limb can include:
As CBD progresses, it may eventually start to cause problems in your other limbs.
The symptoms typically become more severe over several years, although the speed at which they worsen varies.
Some of the main symptoms of CBD are outlined below. Most people with the condition won’t experience all of these.
Walking, balance and co-ordination may get worse. Many people have problems with their speech, which will become slow and slurred.
Some people also develop problems with walking and co-ordination.
You may need to have a brain scan to look for other possible causes of your symptoms, as well as tests of your memory, concentration and ability to understand language.
Read more about the symptoms of CBD.
The diagnosis must be made or confirmed by a consultant with expertise in CBD. This will usually be a neurologist (a specialist in conditions affecting the brain and nerves).
There’s no single test for CBD. Instead, the diagnosis is based on the pattern of your symptoms. Your doctor will try to rule out other conditions that can cause similar symptoms, such as Parkinson’s disease or a stroke.
CBD occurs when brain cells in certain parts of the brain are damaged as a result of a build-up of a protein called tau.
What causes CBD?
The symptoms of CBD get gradually worse over time. They are very variable and many people only have a few of them.
Difficulty swallowing can cause choking, or inhaling food or liquid into the airways. This can lead to pneumonia, which can be life-threatening.
We would like to thank Prof Carlo Colosimo (Università La Sapienza, Rome, Italy) for his help in reviewing this infomation.
Content last reviewed: March 2020
A diagnosis should be made by a specialist with experience in CBD, usually a neurologist. He or she may ask for a brain scan to rule out other causes, and they may also carry out tests to check memory, concentration, and understanding of verbal communication.
There is currently no cure or treatment to stop CBD’s progression but medication and various therapies can relieve symptoms and improve quality of life.
Swallowing difficulties: eating, drinking, and swallowing become progressively more difficult and food may ‘go down the wrong way’. This can lead to chest infections or pneumonia.
CBD has similarities with Progressive Supranuclear Palsy (PSP). Some people with CBD go on to develop PSP, and vice versa.
It is thought there may be some weak genetic link too but the risk of other family members developing CBD is very low.
Corticobasal Degeneration (CBD) is a rare type of parkinsonism that affects people from the age of 40, typically between the ages of 50 to 70. It tends to affect one side of the body more than the other initially, gradually spreading over a few years.
The most common symptoms are outlined below, but many people have only a few symptoms.