Frontotemporal dementia Q&A

Frontotemporal dementia Q&A

Frontotemporal dementia is a type of dementia caused by gradual destruction of neurons in the frontal and temporal lobes of the brain, although the precise cause(s) remains unclear. The initial symptoms are personality changes and behavioral abnormalities, such as an inability to give consideration to others and acting just as he/she pleases, irrespective of the circumstances, but forgetfulness is not a characteristic manifestation. Therefore, the disease tends to be discovered late, as the family/people around simply think that the patient’s personality has changed. Personality changes and behavioral abnormalities are more prominent than other symptoms from the start to the end of the disease. Frontotemporal dementia is also called Pick’s disease.

What is the prevalence of frontotemporal dementia?

The precise incidence of frontotemporal dementia has not yet been established. Available data indicate that approximately 7% of patients visiting dementia outpatient clinics have frontotemporal dementia.

What type of people commonly have frontotemporal dementia?

Frontotemporal dementia often occurs at a younger age than other types of dementia. According to Japanese statistics, frontotemporal dementia is the third most common type of early-onset dementia, occurring in persons younger than 65 years, after vascular dementia and Alzheimer’s disease. Most patients with frontotemporal dementia have developed the disease by the age of approximately 70 years.

Is frontotemporal dementia inherited?

Although 30% to 50% of patients overseas have a family history, almost none of the patients in Japan has a positive family history. Therefore, frontotemporal dementia is not a clearly inherited disease in most patients in Japan. Genetic abnormalities have been found in a very small proportion of patients, indicating that only some types of frontotemporal dementia are inherited.

What are the symptoms of frontotemporal dementia?

Patients become unable to follow rules or give consideration to others, and just act as they please, irrespective of the circumstances. For example, they take out goods from shops without permission or ignore traffic signals when crossing the road. Other symptoms also occur, such as strong preferences, and performing the same tasks at the exact same time each day.

What are the imaging findings of frontotemporal dementia?

Typically, brain MRI shows severe atrophy limited to the frontal and temporal lobes. In addition, in some patients, while MRI may show only mild atrophy, cerebral blood flow single photon emission computed-tomography (SPECT) shows clear hypoperfusion of the frontal and temporal lobes. An accurate diagnosis is often made by specialists’ interpretation of the imaging findings.

What course does frontotemporal dementia follow?

Recently, the course of frontotemporal dementia has been summarized.

Patients with frontotemporal dementia often persist in doing the same thing at the exact same time each day and act without giving consideration to people around them from the early stages. In addition, BPSD, such as getting excited or behaving violently when such acts are stopped, may also be prominent from the early stages of the disease.
Therefore, some patients are admitted to special psychiatric or other hospitals from a relatively early stage.
However, decreased motivation and activity become severe as the disease progresses in all patients. Conversely, behavior without consideration to others, excitement, violence, etc., that are frequently seen in the early stages become less prominent. In regard to repeating the same behaviors at the same time each day, complex behaviors decrease and simple behaviors, e.g., rubbing the knees and tracing wrinkles in the trousers with a finger, persist. With further progression, patients with frontotemporal dementia utter no words and spend time without trying to do anything while sitting in a chair or lying on a bed. Motor functions also become gradually impaired due to disuse syndrome.

What are the currently available treatments for frontotemporal dementia?

Unfortunately, there are no drugs available at present that can cure frontotemporal dementia or stop its progression. When a behavior that causes problems in social life is observed, an attempt could be made to change the behavior to another, more acceptable behavior by adjusting the living environment, or in some cases by admitting the patient to a hospital for a short period.

Source of reference: To know dementia to feel relieved. A guide to dementia management according to symptoms (Medical Review Co., Ltd.)
Supervised by: Masatoshi Takeda
Authors: Hiroaki Kazui, Hiromichi Sugiyama, Shioko Bando