Bruce Willis, the world-renowned star of cinematography, was diagnosed with frontotemporal dementia, the family announced.

Relatives of the 67-year-old Hollywood actor said he would be "stepping away" from his successful career after being diagnosed with aphasia, a condition affecting his cognitive abilities.

In a post on Instagram Thursday, Willis’s daughter Rumer offered an update on her father’s health, confirming his condition has "progressed" and he had been given the "more specific" diagnosis of frontotemporal dementia.

Rumer, who Willis shares with his former partner, actress Demi Moore, wrote: "Our family wanted to start by expressing our deepest gratitude for the incredible outpouring of love, support, and beautiful stories we have all received since sharing Bruce’s original diagnosis."

"In the spirit of that, we wanted to update you about our beloved husband, father and friend since we now have a deeper understanding of what he is experiencing.

"Since we announced Bruce’s diagnosis of aphasia in spring 2022, Bruce’s condition has progressed, and we now have a more specific diagnosis: frontotemporal dementia (known as FTD). Unfortunately, challenges with communication are just one symptom of the disease Bruce faces. While this is painful, it is a relief to have a clear diagnosis finally," Moore said.

According to the NHS, frontotemporal dementia is an "uncommon" form of the disease that causes the sufferer problems with behavior and language and mainly affects those between the ages of 45 and 65.

Willis’ family further explained the condition in a comprehensive statement on the Association for Frontotemporal Degeneration website in which they acknowledged frontotemporal dementia (FTD) is a "cruel disease" and "can strike anyone."

The family added that they hoped media attention on the actor’s condition would raise awareness.

"FTD is a cruel disease that many of us have never heard of and can strike anyone," their statement read.

"For people under 60, FTD is the most common form of dementia, and because getting the diagnosis can take years, FTD is likely much more prevalent than we know.

"Today, there are no treatments for the disease, a reality that we hope can change in the years ahead.

"As Bruce’s condition advances, we hope that any media attention can be focused on shining a light on this disease that needs far more awareness and research."

They added: "Bruce always believed in using his voice in the world to help others and raise awareness about important public and private issues."

"We know in our hearts that – if he could see 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."

Members of Willis’ family signed the statement, including his wife Emma Heming, former wife Moore, and his daughters.

Willis has starred in hit films, including the Die Hard series, Pulp Fiction, Armageddon, Moonrise Kingdom, 12 Monkeys and Looper.

He has five daughters, sharing his three eldest – Rumer, Scout and Tallulah – with Moore, whom he married in 1987. Despite separating in 2000, the pair remained on amicable terms. Willis married actress Heming in 2009. The pair share two daughters, Mabel and Evelyn.

Following Willis’s diagnosis, the charity Dementia UK said: "We’re sorry to hear that Bruce has been diagnosed with frontotemporal dementia (FTD)."

"By choosing to speak publicly about his diagnosis, more awareness can be raised about FTD, and hopefully, it will encourage others to seek advice if they are experiencing concerns about their brain health."

"FTD is the third most common form of dementia in people under the age of 65, but there is still limited awareness among the public and health and social care professionals. This can negatively impact the care that people with the condition receive."

Throughout his career, Willis has been highly commended for many performances, receiving multiple award nominations, including five Golden Globes, of which he won one, and three Primetime Emmys, of which he won two.

What is FTD?

There are different types of dementia, and the frontotemporal form affects regions in the front and sides of the brain. Because it causes problems with behavior and language, aphasia can be a symptom.

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 younger than other forms of dementia, between ages 45 and 65.

The terms frontotemporal disorders and frontotemporal dementia are sometimes shortened to FTD.

What are the other symptoms?

Symptoms can include emotional problems and physical difficulties, such as trouble walking. Symptoms 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 overlapping symptoms with frontotemporal dementia. Many also work with speech therapists to manage communication difficulties and physical therapists to improve movement.

People with the condition are more likely to have complications like falls, injuries, or infections. According to researchers, the average life expectancy after symptoms emerge is seven to 13 years.