Bruce Willis diagnosed with frontotemporal dementia: What to know about the disorder

Blockbuster action movie star Bruce Willis stepped away from acting in spring 2022 after being diagnosed with aphasia, a neurological disorder that impacts the ability to produce and understand words. Now, Willis' condition has progressed and he's received a new diagnosis of frontotemporal dementia, his family announced Thursday (Feb. 16).

"Unfortunately, challenges with communication are just one symptom of the disease Bruce faces," the statement reads. "While this is painful, it is a relief to finally have a clear diagnosis."

The prevalence of frontotemporal dementia (FTD) is somewhat uncertain, because historically, doctors sometimes misidentified the condition as depression, schizophrenia or Alzheimer's disease, according to University of California, San Francisco (UCSF) Health. Current estimates suggest that FTD is the most common form of dementia diagnosed in people ages 60 and younger, although the condition can affect older people, as well. (Bruce Willis is 67 years old.)

FTD actually describes a group of related conditions, all of which arise from the deterioration of cells in the brain's frontal lobe, located behind the forehead, and temporal lobes, situated on either side of the head near the ears, according to the National Institute on Aging (NIA). These conditions are progressive, meaning they get worse over time, and their exact cause is unknown, although studies have flagged several genetic mutations and abnormal proteins that may be involved. 

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The three types of FTD are behavioral variant frontotemporal dementia (bvFTD), primary progressive aphasia (PPA) and movement-related disorders. The first and most common type, bvFTD, primarily involves cognitive symptoms, including having difficulty planning and remembering the order of steps required to complete a task, acting impulsively and losing interest in activities they used to enjoy. Problems with language or movement may emerge as the condition progresses, according to the NIA.

PPA affects a person's ability to use and understand language; it comes in several forms, which differ in their specific symptoms. As their condition progresses, people with PPA can lose the ability to speak, develop problems with memory and reasoning, and show behavior changes similar to those with bvFTD. 

Finally, there are several movement disorders associated with FTD. These impact the regions of the brain that control movement, as well as those involved in thinking and language, in some cases, according to the NIA.

There is no cure for FTD, nor are there any treatments to slow disease progression, according to Johns Hopkins Medicine. People with FTD may be prescribed medications, such as antidepressants, antipsychotics and sleeping aids, to treat individual symptoms of the disorders. They may also work with speech and language pathologists and physical and occupational therapists to adjust to the changes in their abilities. 

People with FTD can live with the disorders for many years, but as they worsen, they may engage in dangerous behaviors and otherwise lose the ability to care for themselves, according to Stanford Medicine. They also face an increased risk of infections and fall-related injuries. 

"Bruce always believed in using his voice in the world to help others, and to raise awareness about important issues both publicly and privately," the Wills family's statement reads. "We know in our hearts that — if he could today — he would want to respond by bringing global attention and a connectedness with those who are also dealing with this debilitating disease and how it impacts so many individuals and their families."