Understanding Primary Progressive Aphasia, The Lesser Known Dementia

Older woman sitting in chair with a younger woman with arms around her

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Key Takeaways

  • Primary progressive aphasia (PPA) is a less common form of dementia, and one that not as many people are aware of.
  • It primarily affects speech and language, with memory loss becoming more apparent further on in the condition.
  • While it's less common, research into PPA is ongoing and there is support available for people living with the condition and their loved ones.

According to the Centers for Disease Control and Prevention, around five million adults were living with dementia in the U.S. in 2014. Most of these adults would have been living with Alzheimer’s disease—it’s the most common form, and it’s the one that probably comes to mind for many of us when we think about dementia.

However, there are many different types—some of which we’re far less familiar with. One such type of dementia is primary progressive aphasia, or PPA.

Aphasia has been in the news in recent months, largely because Bruce Willis’ family announced that the actor has the condition. Affecting language and speech, it can be caused by brain damage or a stroke, while migraines can cause temporary aphasia.

However, while recovery from some forms of aphasia can be possible, PPA will only get worse over time. 

What is Primary Progressive Aphasia?

Primary progressive aphasia is a form of dementia characterized by the loss of language function.

Whereas we often associate dementia with memory loss, memory in people with PPA is generally not overly affected until the later stages.

The loss of speech skills often begins subtly, before progressing to an almost complete inability to speak. As the condition progresses, it can begin to resemble other dementias more readily, with changes in memory, personality, judgment, and attention, and eventually movement and swallowing may be affected.

Charles Marshall, PhD, MRCP

We need to improve awareness that dementia can affect language as well as memory to ensure that people with PPA are diagnosed promptly and accurately.

— Charles Marshall, PhD, MRCP

People tend to be affected with PPA in late-middle-age, meaning that it can be an early-onset dementia.

The age of onset can differ from patient to patient, however, as can the progression of the condition; someone may live for over a decade after diagnosis, and keep a high level of independence for a number of years.

Why there can be so much difference between individuals with PPA is something that scientists are researching.

PPA can, in around 10% of cases, be genetic. This means that “a specific faulty gene might be causing these problems, but this is only the case for a small minority of people with PPA,” says Chris Hardy, PhD, a senior research fellow at the Dementia Research Centre at the University College London Queen Square Institute of Neurology.

How is PPA Caused?

Because PPA differs from other forms of dementia like Alzheimer’s, people with the condition can often take care of themselves independently, live their normal life, and even work, while they have the condition.

While there is some research on PPA, it’s not as widely understood as some other dementias—however, it has been studied by a number of researchers, and there is an understanding of how it occurs.

Charles Marshall, PhD, MRCP

We hope that research to improve this understanding will allow us to develop treatments for these devastating conditions.

— Charles Marshall, PhD, MRCP

“Primary progressive aphasias are unusual types of dementia where certain proteins build up in the brain and damage nerve cells in the brain’s language areas,” says Charles Marshall, PhD, MRCP, a clinical senior lecturer and honorary consultant neurologist at the Wolfson Institute of Population Health.

“We need to improve awareness that dementia can affect language as well as memory to ensure that people with PPA are diagnosed promptly and accurately,” Marshall explains.

“We don’t completely understand why the abnormal proteins accumulate in the brain, or how it is that they selectively damage nerve cells that are important for language. We hope that research to improve this understanding will allow us to develop treatments for these devastating conditions.”

There’s currently more research being carried out into PPA, including at the Dementia Research Centre, something that Hardy hopes “will lead to breakthroughs in the future in terms of diagnosis, care, support, and clinical trials.”

The Subtypes of PPA

There are three main types of PPA: the nonfluent/agrammatic variant, the semantic variant, and the logopenic variant.

  • Nonfluent/agrammatic variant PPA (nfvPPA): Individuals with this variant tend to have slower, more hesitant, and distorted speech, with mispronunciations, grammar and syntax errors, and missing words. 
  • Semantic variant PPA (svPPA): Individuals with the semantic variant present with well-structured speech, but difficulty in naming words—particularly nouns—and understanding the meaning of some words. "People with svPPA can usually speak quite fluently until fairly late into the disease," says Hardy, "although they will often start to use more general words because they’ll also have difficulties remembering the correct words to use."
  • Logopenic variant PPA (lvPPA): Individuals with the logopenic variant may find it difficult to find the right words, or to understand others.

“In nfvPPA and svPPA, the types of proteins that we see going awry are usually the same as those seen in a larger group of dementias called frontotemporal dementia (FTD), whilst lvPPA is most often caused by problems with the same proteins that we see in typical (memory-led) Alzheimer’s disease,” says Hardy.

What Are the Symptoms?

With different types of PPA, the symptoms can differ. However, across the condition as a whole, the following are among the initial symptoms to watch out for:

  • Slowed speech and hesitations
  • Abnormal word order
  • Substitution of words
  • Forgetting the names of familiar objects or people
  • Spelling errors
  • Difficulty following a conversation or understanding what words mean
  • Mispronouncing words

It’s worth remembering that not everyone will have symptoms fitting into one of the three main types, and Hardy explains that these individuals might be described as having a diagnosis of “mixed PPA” or “PPA not otherwise specified.”

Getting Support

There’s no cure for primary progressive aphasia, but there are ways to help manage the condition.

Some people with PPA find it useful to have speech therapy, while some carry identification cards that explain the condition to other people for ease of communication—particularly when they’re independent enough to be able to go out on their own but perhaps not capable of explaining their condition through speech.

Supporting a loved one with PPA can be difficult, but there are things that you can do to help them.

Do your best to be patient and understanding, checking that you understand what they mean, and speak clearly too. Your loved one might find talking one-on-one easier than talking in larger group settings, or find it easier to write things down than speak.

Hardy suggests joining groups or organizations, like the U.K.-based Rare Dementia Support, while there’s also the U.S.-based Association for Frontotemporal Degeneration.

There are various barriers preventing people from getting the right care, which can include speech and language therapies and even just healthcare providers who are familiar with the condition.

As PPA is still something many people aren’t familiar with, getting the right support can be tricky, but it makes raising awareness all the more important.

What This Means For You

Dementia can be difficult to think about or discuss—particularly when it comes to types we don't know as much about. If you think that you or a loved one might be experiencing symptoms of primary progressive aphasia, speak to your doctor, or get in touch with the Dementia Research Centre to find out more about ongoing research into the condition.

5 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Centers for Disease Control and Prevention. What is Dementia?

  2. Mesulam M. Primary progressive aphasiaAnn Neurol. 2001;49(4):425-432. doi:10.1002/ana.91

  3. Marshall C, Hardy C, Volkmer A, et al. Primary progressive aphasia: a clinical approachJ Neurol. 2018;265(6):1474-1490. doi:10.1007/s00415-018-8762-6

  4. National Aphasia Association. Primary Progressive Aphasia.

  5. Mesulam Center for Cognitive Neurology and Alzheimer’s Disease. Symptoms & Causes of PPA.