Frontotemporal Dementia
Frontotemporal dementia is caused by a group of disorders that gradually damage the brain’s frontal and temporal lobes. These damages cause changes in thinking and behaviours. Symptoms can include unusual behaviours, emotional problems, trouble communicating, challenges with work, and difficulty with walking. Frontotemporal dementia (FTD), sometimes called frontotemporal disorders, is rare and tends to occur at a younger age than other dementias. About 60% of people with frontotemporal dementia are 45 to 64 years old.
FTD is progressive, meaning symptoms get worse over time. Some people live more than 10 years after diagnosis, while others live less than two years after they are diagnosed. High levels of care, such as 24-hour care, may be needed over time. Once the person is diagnosed, it is important to plan ahead for financial, legal, and care arrangements that may be needed as the disease progresses.
What Are the Types of Frontotemporal Dementia?
There are several disorders that can result in frontotemporal dementia, all of which can affect middle-aged and older adults.
Behavioural variant frontotemporal dementia (bvFTD) is the most common frontotemporal disorder. It causes changes in personality, behaviour, emotions, and judgment.
Primary progressive aphasia (PPA) involves changes in the ability to communicate — to speak, read, write, and understand what others are saying.
Movement disorders happen when the parts of the brain that control movement are affected. There are two types of rare movement disorders associated with FTD: corticobasal syndrome and progressive supranuclear palsy. Other movement-related disorders include frontotemporal dementia with parkinsonism and frontotemporal dementia with amyotrophic lateral sclerosis (FTD-ALS). Symptoms can vary among these movement disorders.
What Causes Frontotemporal Dementia?
The underlying causes of frontotemporal dementia are not yet fully understood. People with FTD have abnormal amounts or forms of proteins called tau and TDP-43 inside nerve cells, or neurons, in their brain. The neurons die because the build-up of these proteins causes damage. In some cases, mutations or changes in genes can be identified as the cause of FTD. For example, about 10% to 30% of bvFTD cases can be attributed to genetic causes. People with a family history of FTD are more likely to have a genetic form of the disease.
What Are the Signs and Symptoms of Frontotemporal Dementia?
The signs and symptoms of frontotemporal dementia vary from person to person and the order in which they appear can also vary. Changes in the frontal lobe of the brain are generally associated with behavioural symptoms and may also lead to movement symptoms. Changes in the temporal lobe generally lead to disorders of language and emotion.
Symptoms of frontotemporal dementia and associated disorders may include:
- Decreased energy and motivation
- Lack of interest in others
- Inappropriate and impulsive behaviours
- Not acting considerate of others
- Repeating an activity or word over and over again
- Changes in food preferences and compulsive eating
- Increased interest in sex
- Neglect of personal hygiene
- Emotional flatness or excessive emotions
- Difficulty making or understanding speech
- Inability to make common motions, such as using a fork
- Problems with balance and walking
- Increased clumsiness
- Slow movement, falling, body stiffness
- Restricted eye movements
- Shaky hands
- Muscle weakness and loss, fine jerks, wiggling in muscles