Frontotemporal dementia

Frontotemporal dementia (FTD) is a form of dementia that often occurs at a young age. Most diagnoses occur between 40 and 60 years old. At a young age it is, after Alzheimer's disease, the most common form of dementia. Genetics play a more significant role in FTD compared to other forms of dementia.

Cause of frontotemporal dementia

Frontotemporal dementia affects the frontal lobe (behavioral area) and/or the temporal lobe (language area). 

In 25 to 40% of cases, frontotemporal dementia is hereditary.  An abnormal gene affects the tau protein, which plays a crucial role in the transport of substances within brain cells. Ultimately, brain cells die due to this genetic abnormality.

Previously, frontotemporal dementia was also known as Pick's disease. In some patients, cells in the frontal and temporal lobes swell into balloon-like shapes. These cells are called "Pick cells." However, these specific cells are not present in all cases, which is why the term is becoming less common.

Symptoms of frontotemporal dementia

Changes in behavior, language, or motor skills can indicate FTD. Memory problems often follow in later stages. The initial symptoms depend on which part of the brain is damaged.

We refer to the behavioral variant when the frontal lobe is first affected. This part of the brain regulates whether our behavior aligns with our norms and values. The initial symptoms of frontal lobe dementia include:

• Disinhibited behavior, such as eating quickly and excessively without stopping.
• Inappropriate comments and jokes.
• Lack of consideration for others, reduced empathy.
• Lack of initiative in activities one used to enjoy.
• Impulsive decisions, such as sudden big expenditures.

We refer to the language variant when the temporal lobe is first affected. The initial symptoms concern writing, language, and speech:

• Reduced vocabulary, difficulty finding the right words.
• Difficulty with grammar, formulating incorrect sentences.
• Difficulty with writing.
• Difficulty understanding spoken or written language.

Some people with frontotemporal dementia experience motor symptoms as the first signs, including:

• Problems with balance.
• Weak or trembling muscles.
• Stiff movements.

In FTD, damage can extend to the parietal lobes of the brain. The parietal lobe area is involved in spatial orientation and language comprehension. This leads to difficulties in navigation and exacerbates language problems.

Progression of frontotemporal dementia

Frontotemporal dementia often occurs at a relatively young age. Most people who develop the disease are between 40 and 60 years old. Life expectancy averages six to eight years after diagnosis.

The initial phases of all three variants generally progress gradually. There are stable periods lasting several weeks or months, which complicates symptom recognition. Initial symptoms of the behavioral variant often resemble depression or burnout.

The progression in later stages is unpredictable. Some people experience a gradual decline, while others deteriorate rapidly.

Initially, clear differences exist between the three variants. Later in the disease, these differences blur. In most cases, behavioral, language, and motor problems are present.