Introduction on dementia

Dementia is a collective term for diseases that affect the health of the brain. There is a memory disorder in combination with one or more other cognitive disorders (aphasia, apraxia, agnosia, disorder in the executive functions) and a negative influence on daily functioning.
It will have to be investigated whether there are other causes for the cognitive disorders.

Both mentally and physically, the body will deteriorate. There are over fifty types of dementia. These types are different, but they have in common that the brain is damaged and that the process is
progressive.
Although there are over fifty types of dementia, the following types are the most common:

• Alzheimer's disease
• Vascular dementia
• Frontotemporal dementia (this page)
• Lewy body dementia

Of these four types, Alzheimer's disease is the most common. Vascular dementia is the next most common.

Frontotemporal dementia (FTD) is a form of dementia that sometimes begins at a younger age. FTD is also called Pick's disease. The most common cause of dementia, especially in people under 60, is frontotemporal degeneration.

Changes in behavior and language are usually the first to be noticed. Changes can occur insidiously. A person may take less initiative and appear more apathetic. Some people withdraw socially or show less emotion.

Apathy even predicts some forms of dementia years before the first symptoms appear, researchers from the Donders Institute and the University of Cambridge concluded in December 2020.

Language and speech may be affected. The cause is the death of brain cells in the frontal lobe (behavioral area) and in the temporal lobe (behavioral and language area). These brain areas are also responsible for decision-making, coordination and for emotional responses and language skills.

Frontal Lobe

Temporal Lobe

Symptoms

Frontotemporal disorders are classified into three groups depending on the first symptoms that occur:

• Slow change in behavior/personality: This form is characterized by changes in personality, behavior (disinhibition, agitation, apathy), judging situations/critical thinking, social norms, etiquette, emotional flattening and a lack of insight into the disease. It is the behavioral variant of FTD and is called frontal syndrome.

• Change in language: This form is characterized by early changes in language skills, such as speaking, understanding, reading and writing (Primary progressive aphasia, Semantic dementia).
  • Semantic dementia is a form of frontotemporal dementia which causes a person to have problems with words and language. The language is becoming impoverished. The words lose meaning and the person replaces words with standard words. The words apparently still come out of the mouth easily, but with less and less vocabulary. The damage is therefore in the area of ​​the brain where language is regulated, the left temporal lobe. More information behind this link.

• Changes in motor skills: This form is characterized by difficulties with movement, such as tremors, difficulty walking, frequent falls and problems with coordination; Corticobasal Syndrome (CBD) and Progressive Supranuclear Palsy/Paralysis (PSP).

Distinguishing from other forms of dementia

FTD can be distinguished from other forms of dementia in two important ways:

• FTD is a gradual, progressive decline in behavior and/or language (with memory initially functioning well). As the disease progresses, people have more difficulty planning or organizing, behaving appropriately in social or work settings, and taking care of themselves, resulting in dependency on others. Behavioral changes, disinhibited, agitated, and/or apathetic, changes in speech and language are often the first to be noticed.
• FTD often begins to manifest around the age of 50 or 60, but it can occur as early as age 21 and also as late as age 80. Roughly 60% of cases occur in people aged 45-64. (Knopman, 2011). As a result, FTD can affect work and family life in a way that is different from dementia that starts in an older person.
• Putting objects in the mouth (hyperorality) was added to the diagnostic criteria in 2011. This often occurs in the early stages of FTD.
• Sound hallucinations occur in FTD. The hallucinations are usually auditory in nature, in contrast to the hallucinations in Lewy Body dementia, which are usually visual (seeing) in nature.

Causes

• In 25 to 40% of cases, FTD is hereditary. Some hereditary forms of FTD are caused by an abnormal gene. As a result, the tau protein, which plays a role in the transport of substances in the brain cell, no longer functions properly and the brain cell eventually dies.

• Protein clumping

  Some clinical symptoms of FTD are associated with different types of protein clumping in the brain.

• Loss of specific nerve cells
  Spindle neurons (also called von Economo neurons) are unique nerve cells responsible for complex behavior. These cells are part of a larger group of cells that selectively disappear in the brains of people with FTD.

• Disruption of Lysosomal Processes
  Within the different disease subgroups of FTD, a disruption of the lysosomal processes has also been identified. In both FTD-TAU and FTD-TDP, more lysosomes were found.
  Lysosomes contain enzymes that can break down and digest foreign particles, substances, micro-organisms or food that have entered the cell. One of the functions of the lysosome is the breakdown of bacteria and cell organelles that no longer function, such as mitochondria.
  The lysosomal protein HEXA was found to be present in higher amounts in FTD-TDP compared to FTD-TAU, Alzheimer's and healthy brain bank donors.

Treatment

There is no treatment yet that can stop or reduce the progression of the disease. Research into FTD is expanding, which increases knowledge about this disease.
The risk of a wrong diagnosis is high because the first symptoms occur when people are still young, too young to become demented. A wrong diagnosis is often made initially, for example a psychiatric disease or Parkinson's disease.
The importance of a correct diagnosis is great. Medicines that are wrongly prescribed can be harmful to a person with FTD.

More information:
Association for Frontotemporal Degeneration

Inheritance of Frontotemporal Degeneration

FTD Talk (a website by a group of scientists in the UK)

The association for Frontotemporal Degeneration

From the site of the association you can download this PDF:

Guide for Managing a New Diagnosis – FTD

Information from a Dutch care professional about clients with FTD:

• https://www.braininjury-explanation.com/information/brain-injury-professionals/specialized-caregiver-in-psychogeriatrics#ftd

More information about two frontotemporal diseases: