What is primary progressive aphasia? When actor Bruce Willis was diagnosed with aphasia in the spring of 2022 sparked interest in exactly what the condition is and how it affects those who have it.
While Willis later received a more specific diagnosis of frontotemporal dementia in February of this year, the two conditions are closely related.
Primary progressive aphasia
Generally, aphasia is classified as a neurogenic language disorder that causes a loss of language—both the ability to produce language and the ability to understand it. The condition can be caused by a stroke, head injury, brain tumor, or other brain infection or disease.
The primary progressive aphasia (PPA) with which Willis was diagnosed is a progressively worsening form of aphasia that is also recognized as a subtype of frontotemporal dementia. Unlike some other forms of aphasia, there is no way to slow this condition and there is no way to cure it.
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Early symptoms of aphasia
PPA is considered rare: Fewer than 50,000 people in the U.S. have it, according to the Genetic and Rare Disease Information Center.
But Aaron Wilkins, PhD, speech-language pathologist and assistant clinical professor at Northwestern University, has particular expertise in such degenerative communication conditions. He says most people who develop PPA first realize there’s a problem when they exhibit word-finding difficulties or anomia.
“We all have trouble finding words sometimes, but it’s the frequency that really changes [PPA]says Wilkins. “For every conversation, or even for every sentence, it is difficult to find a word.”
At first, people with PPA may fill sentences with pauses and hesitation, while others may use the wrong words entirely—resulting in sentences that don’t make sense. Progressive anomia usually leads to medical referrals during which investigations and then diagnosis are made.
Later symptoms of aphasia
Although PPA usually begins with a person’s inability to speak properly, these symptoms gradually become much worse as the left temporal lobe (the part of the brain responsible for recalling language) deteriorates. Often patients lose the ability to write, read and even understand the words spoken by other people.
“While their communication partner is talking, they may not understand anything that’s being said,” says Wilkins. “They’ll know the person is talking, but they won’t be able to put meaning to those words.”
Despite this loss of language function, the disease often does not bring with it any other loss of cognitive function—especially in the first two years after onset. PPA changes the brain at a cellular level, Wilkins says, but only in areas involving language. This differs dramatically from other forms of dementia such as Alzheimer’s, which involve much more than the overall structure of the brain.
Only about half of PPA diagnoses actually result in behavioral or cognitive changes. Although these patients do not lose track of how the world works or who someone is – and can still function normally in many other ways – they are forced to endure the gradual cessation of communication forever.
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Stages of primary progressive aphasia
The typical onset of PPA occurs around age 60, but it can strike anywhere between the ages of 40 and 80.
The disease progresses in a highly variable manner, and Wilkins has seen both rapid and gradual declines in the patients he treats. The average rate of progression is five to 10 years, he says, although some people experience complete language loss in four to five years and others won’t get there for 15 or 20.
Cognitive testing, independent of language function, is usually performed to confirm the diagnosis of PPA in the first two years. But if other cognitive or behavioral changes occur in the same time period, Wilkins says, it indicates some other condition.
And while PPA is usually associated with frontotemporal dementia, rarer cases may be associated with Alzheimer’s disease. In this case, patients usually see symptoms beyond language loss over time.
Behaviorally, about half of PPA patients experience depression due to the overwhelming frustration and nature of their condition. Others with more advanced PPA may have difficulty inhibiting certain behaviors because the frontal lobe of the brain — responsible for executive functioning — is affected, Wilkins says.
Treatment of aphasia
Even with such a dire prognosis, Wilkins and other speech therapists have seen positive effects as they help patients cope with the gradual loss of language skills.
“We’re trying to keep communication as natural as possible as we move to a more global way of communicating,” he says. “And then, ultimately, it’s really limited to these alternative systems that we’ve created.”
While a person can still speak but has trouble finding words, for example, therapists often encourage workarounds: like describing things or using associations and synonyms for words they can’t remember.
Relying on multiple methods of communication as early as possible, Wilkins says, helps both patients and their families better adjust to their new normals.
Other therapies for aphasia
Patients are also encouraged to use their hands while communicating, he adds, using functional gestures such as pantomime, body language and facial expressions. Therapists also use imagery to aid communication; on the low-tech end, this includes pictographic books that allow one to simply point to what one needs or wants.
From a high-tech perspective, devices such as mobile phones and electronic tablets can speak for the patient when they activate images by touch. In some cases, Wilkins says, patients have recorded their own voices while they still can—allowing them to digitally store the words in their own voice for the future.
Working with communication partners like loved ones is also critical, he says. Although there is no way to cure PPA, there are still ways to make the best of a terrible diagnosis.
“Usually the best results are when you can work with both the patient and family members or other support systems they may have,” Wilkins says. “That combination makes a big difference.”
Read more: The man who lost his tongue overnight