What is Frontotemporal Dementia? Miller School of Medicine

The name frontotemporal degeneration refers to the loss of cells in the frontal and temporal lobes of the brain. Conditions affected by this cell loss include disorders affecting behavior, language and movement. These conditions include behavioral variant of FTD (bvFTD), progressive primary aphasia (PPA), progressive supranuclear palsy (PSP), corticobasal syndrome (CBS) and amyotrophic lateral sclerosis with FTD (ALS-FTD).

The term Frontotemporal Dementia (FTD) often refers to both bvFTD and PPA. Approximately 5% of all dementia patients present with FTD, but it is a lot more common (>30%) amongst dementia patients under the age of 60. Frontotemporal dementia is sometimes also referred to as Pick’s disease.

FTD is unique in its loss of social cognition or language disturbances; though it often gets misdiagnosed as Alzheimer’s disease (AD), depression or other psychiatric conditions. FTD differs from AD as generally memory itself is not affected and it typically starts at an earlier age. The majority of FTD cases occur between 35y and 64y, whereas AD is typically a late onset (>65y) disease.

Our study at the HIHG focuses on genetic factors underlying FTD (bvFTD and PPA).

Different forms and symptoms of FTD

As the frontal and temporal lobes of the brain are particularly responsible for language and behavior, we can generally classify symptoms in a behavioral form and a language variant form of FTD; though patients can present with symptoms of both forms.

Behavioral variant of FTD (bvFTD)
The behavioral variant of FTD (bvFTD) is the most common form of Frontotemporal Degeneration (~50%) as well as subgroup FTD, affecting over 60% of patients with FTD. Patients with bvFTD often present with personality changes, apathy and a progressive reduction of appropriate social behavior, judgment, empathy and self-control. Patients with bvFTD often do not recognize the changes in their behavior or exhibit concern for the effect of their behavior.

Examples of such changes include
- Disinhibition; e.g. making uncharacteristic rude comments
- Apathy; e.g. loss of interest in previous hobbies
- Changes in eating habits; e.g. binge eating
- Executive dysfunction; e.g. difficulty planning daily activities
- Lack of insight; e.g. failure to recognize consequences of actions
Due to the type of symptoms, bvFTD is commonly misdiagnosed as depression, Alzheimer’s disease or a psychiatric disorder.
Language variant of FTD or Progressive Primary Aphasia (PPA)

The language variant of FTD or Progressive Primary Aphasia (PPA) is mostly hallmarked through the progressive loss of the ability to speak, read and understand what others are saying. A recent example of someone affected by aphasia is Bruce Willis, the actor. Aphasia can be caused by brain cells loss (described here as Progressive Primary Aphasia or PPA), stroke, brain injury or a brain tumor. Bruce Willis’s aphasia was determined to be PPA.

Depending on the most common elements of language that are affected, three subforms of PPA are used.

Nonfluent variant of PPA (nfvPPA)

These patients find it increasingly difficult to speak because of difficulty forming sounds with their lips and tongue and make more mistakes grammatically (e.g. leaving out words, mixing up word order), but meaning of individual words is not affected.

Semantic variant of PPA (svPPA)

These patients progressively lose the meaning of individual words. The ability to speak is unaffected but words are omitted or replaced with incorrect ones, as patients are unable to recall the names of objects.

Logopenic variant of PPA (lvPPA)

These patients have trouble finding words while speaking. They are still able to speak/form sounds and are still able to recognize words but their speech will be distorted as they are unable to retrieve the correct word when talking.

For more information on FTD in general, national resources, caregivers information, etc., please visit the Association for Frontotemporal Degeneration’s website: https://www.theaftd.org/

If you are looking for an evaluation, please make an appointment with UHealth neurologists here.

What is Frontotemporal Dementia?

Different forms and symptoms of FTD

Behavioral variant of FTD (bvFTD)

Examples of such changes include

Language variant of FTD or Progressive Primary Aphasia (PPA)

Nonfluent variant of PPA (nfvPPA)

Semantic variant of PPA (svPPA)

Logopenic variant of PPA (lvPPA)