Corticobasal Degeneration: How This Terrifying Brain Disorder Affects Body And Mind

Corticobasal degeneration is a progressive brain disorder characterized by nerve cell loss and shrinking in many areas of the brain. These portions of the brain can include the basal ganglia and cerebral cortex. The disease starts gradually, and usually begins at or around the age of 60. It can also be called “corticobasal ganglionic degeneration” and it is part of the “pick complex” of neurodegenerative diseases because it shares similarities with frontotemporal dementia.

CBD's History And Background

Corticobasal degeneration was first identified in 1968 by Rebeiz and his research associates. Initially, the researchers referred to this neurodegenerative disease as “corticodentatonigral degeneration with neuronal achromasia.” Although the precise cause of CBD is not currently known, the disease causes serious damage to the basal ganglia. Much of the recent advancements in the understanding of the disease comes within the past decade, due to it being formally recognized by medical science.

Corticobasal Degeneration: What Are The Signs And Symptoms?

People who are suffering from corticobasal degeneration will usually have a movement disorder or cognitive deficits. As the disease gets worse, most will have both types of symptoms and often with a delay of onset for about two to three years. The movement issues associated with the disease can mimic Parkinson’s disease (PD). However, unlike Parkinson’s disease, people with CBD will typically not improve with medications and many of the symptoms are not found in those with Parkinson’s. A key feature of movement issues in corticobasal degeneration is muscle rigidity, though tremors are not as common. Most often the symptoms will start in one hand, leg or arm.

Many people with CBD will complain of subtle changes in feeling or have an inability to make the affected limb or limbs follow a command. This deficit is called apraxia and it may be confused with weakness or clumsiness. There could also be trouble with doing specific tasks such as opening a door or brushing one’s hair. 

Uncontrolled jumping of the limbs when it is gently tapped is called myoclonus. Lastly, individuals will often complain the affected limb doesn’t feel like a part of their body, it’s a phenomena called “alien limb.” Sometimes it will raise up on its own, with the person having no control. 

Cognitive Disabilities

Those with CBD who present with cognitive difficulties are often misdiagnosed with some form of dementia or Alzheimer’s disease. It’s only after developing movement issues that most people will receive a proper diagnosis. Occasionally, a diagnosis of corticobasal degeneration isn’t made until after a person’s brain is examined during an autopsy and it has ballooned neurons, neuronal inclusions and other abnormalities from deposits of the tau protein.

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Another issue associated with this disease is language difficulties. This is most commonly witnessed as having difficulty with the expression of language, such as finding the “right” word or naming something correctly. Solving mathematical equations, reading and writing can also be impaired. It’s very common to see personality changes, repetitive or compulsive behaviors, and inappropriate behaviors in those with CBD.

Corticobasal Degeneration: Diagnosis, Complications And Outlook

Diagnosis 

Corticobasal degeneration is diagnosed based upon the signs and symptoms a patient presents with. Most often, it involves a blood test and an MRI of the brain to rule out any other disorder. There are currently no medications that can be used to treat CBD. 

However, some medications can help control the symptoms of the disorder. Some individuals show improvement in their movements when they are prescribed the same drugs used to treat the symptoms of Parkinson’s disease. For those with severe muscle stiffness, muscle relaxers and Botox injections could be useful. In people who experience depression and motivational issues, being treated with antidepressants can be beneficial. In severe symptoms, antipsychotic drugs can alleviate agitation but should not be taken unless absolutely necessary.

Complications Of Corticobasal Degeneration 

In itself, CBD is not fatal, but it can wind up causing serious health complications. Having difficulty swallowing and a higher risk of choking or inhaling foods or liquids into the airway. If a person aspirates on food or liquids, it can result in aspiration pneumonia. This is an infection which is caused by a small piece of food entering the lungs.

The symptoms associated with aspiration pneumonia include a high temperature, fatigue, shortness of breath, chest pains, bluing of the skin and wheezing upon breathing in. Sometimes there is also a cough that can produce a bad smelling phlegm and it could contain small amounts of pus or blood. 

It’s important to get emergency medical attention if you suspect inhalation pneumonia or acute respiratory distress syndrome, because without treatment these conditions can be fatal. 

Prognosis for Corticobasal Degeneration

The gradual loss of brain tissue and the symptoms of CBD usually start between the ages of 45 and 70 years old. Initially, a person can experience stiffness, shakiness, slowness and clumsy movements and difficulty with comprehension and speaking. While in the past, many individuals were misdiagnosed with Parkinson’s disease, those with CBD may also get other symptoms that are not common with PD and it is sometimes referred to as a ‘Parkinson’s plus” syndrome.

A person with corticobasal degeneration will commonly become disabled and immobile within five years of the onset of the disease. Within about a decade, pneumonia or another bacterial infection could lead to life-threatening or fatal complications.

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There have been many significant advancements made in the field of understanding corticobasal degeneration, but more research is needed for better treatment options to become available. The University of California San Francisco is actively involved in researching the cause or causes of CBD and how the disease progresses. With the wealth of information available online and ongoing research concerning CBD, it’s possible to find a trial study or to locate a support group of others dealing with the same prognosis. As with many diseases, CBD has a bleak outlook, but the more a person knows and becomes educated about it, the less threatening the future may be.