Bruce Willis' functions will get "worse and worse" as his frontotemporal dementia continues to advance, CBS News medical contributor Dr. David Agus told "CBS Mornings."
"This is a progressive disorder ... He won't be able to do many activities that we all do in life," Agus said.
Agus, according to CBS, says that Willis will probably go through some of the symptoms of FTD and may require in-home care as a result.
The announcement came from Willis' family about the diagnosison Thursday in a statement, writing that while it is a challenging diagnosis, the family was relieved to have "clear answers."
Agus told CBS Mornings that on average it usually takes several years to make the diagnosis of frontotemporal dementia from when symptoms first present.
It’s caused by damage to neurons, the brain’s information carriers, but the underlying reasons for a particular case are often unclear. People with a family history of the condition are more likely to develop it. It’s rare and tends to happen at a younger age than other forms of dementia, between ages 45 and 65.
The terms frontotemporal disorders and frontotemporal dementia are sometimes shortened to FTD.
It makes up about 20% of dementia cases, second only to Alzheimer's, making FTD not "uncommon" and, Agus said, often underdiagnosed.
WHAT ARE OTHER SYMPTOMS OF FTD?
Symptoms can include emotional problems and physical difficulties, such as trouble walking. Symptoms tend to worsen over time, though progression varies by person.
The statement from the actor's family said communication problems “are just one symptom of the disease Bruce faces.”
CAN FTD BE TREATED?
There are no treatments to slow or stop the disease, but some interventions can help manage symptoms.
Some patients receive antidepressants or drugs for Parkinson's, which has some overlapping symptoms with frontotemporal dementia. Many also work with speech therapists to manage communication difficulties and physical therapists to try to improve movement.
People with the condition are more likely to have complications from things like falls, injuries or infections. The average life expectancy after symptoms emerge is seven to 13 years, according to researchers.
The Associated Press and CBS News contributed to this article.
