Dementia is the blanket term given to a number of symptoms caused by disorders in the brain; there are many different types of Dementia.
Alzheimer’s is the most common type of dementia overall, but Frontotemporal Dementia (FTD) is the most common form of dementia for people under the age of 60.
FTD is also hereditary, and can sometimes occur in several people in one family across different generations.
What is Frontotemporal Dementia?
FTD is the name given to dementia caused by progressive damage to the frontal and / or temporal lobes of the brain.
The frontal lobes control mood, social behaviour, attention, judgement, planning and self control; damage to that area of the brain can lead to reduced intellectual abilities and changes in personality, emotion and behaviour.
In a healthy brain, the two sides of the temporal lobes function together to help us understand what we hear and see. Those who are living with FTD may experience difficulty recognising objects or understanding and taking part in conversation.
Unlike some other forms of dementia, people with FTD often don’t lose their memory, particularly in the early stages. In the early stages of FTD, the most common change observed is change of personality.
The different types of FTD
There are three different types of FTD – Behavioural Variant FTD, and two language variants – Progressive Non-Fluent Aphasia, and Semantic Dementia.
Behavioural Variant FTD
The Behavioural Variant is the most common type of FTD.
The most common symptoms of Behavioural Variant FTD are:
- Loss of inhibitions
- Become apathetic towards people and things
- Lose motivation but they aren’t sad
- Lose empathy
- Show repetitive behaviours
- Crave sweet food
- Forget table etiquette
- Struggle with planning
- Find it difficult to make decisions
- Tend not to lose memory in the early stages
There are two Language Variants of FTD, Progressive Non-Fluent Aphasia and Semantic Dementia
Both progressive non-fluent aphasia and semantic dementia involve difficulty with language. The symptoms usually emerge gradually over a couple of years.
Progressive Non-Fluent Aphasia
The symptoms of Progressive Non-Fluent Aphasia are:
- Slow, hesitant speech
- Mistakes in grammar
- Leaves out link words such as ‘to’ or ‘the’
- Failure to understand complex sentences
The symptoms of Semantic Dementia are:
- Speech is fluent
- Lose understanding of what objects are
- Vocabulary is lost, for example, they might ask, ‘What is water’
- Might have trouble finding the right word
- Might use less precise words, for example ‘animal’ instead of ‘dog’
- Difficulty recognising familiar people
- Difficulty recognising common objects
What are the causes of FTD?
In FTD, abnormal ‘clumps’ of proteins kill nerve cells in the frontal and temporal lobes of the brain.
FTD is more hereditory than other types of dementia. Around one third of the people who are diagnosed with FTD have some family history of dementia. Around 10-15 per cent of people with FTD have a very strong family history of the condition, with several close relatives in different generations affected. Children or siblings of a person with FTD have a 50 per cent chance of carrying the same gene mutation.
Hereditary FTD is inherited from a parent as a defect in one of three genes:
- GRN, or
Getting a diagnosis
If you suspect that you, or someone you care about, is showing signs of dementia, the first place to visit is the GP.
People who have FTD may not realise there is a problem with their behaviour, and may be reluctant to seek medical help.
The symptoms of FTD can easily be confused with other conditions such as Alzheimer’s, depression, or even stroke, so testing, scans, and close examination are required before an accurate diagnosis can be made.
A specialist will gather information from the person themself, someone who knows them well, and make their own observations, before making a diagnosis.
Tests for memory, social awareness, and behavior are also sometimes used in a diagnosis of FTD. Computerised Tomography and Magnetic Resonance Imaging (MRI) scans can provide evidence of patterns of damage in the brain.