Frontotemporal Dementia

Original Editor - Kirenga Bamurange Liliane Top Contributors - Kirenga Bamurange Liliane, Lucinda hampton, Kim Jackson and Aminat Abolade

Introduction

Frontotemporal lobar degeneration (FTLD) is the pathological description of a group of neurodegenerative disorders characterised by focal atrophy of the frontal and/or temporal cortices. These results in variable clinical manifestations collectively known as frontotemporal dementia (FTD) syndromes.

FTD belongs to the family of tauopathies.  

FTD is characterized by loss of intellectual functions, eg memory problems, impaired abstract thinking, reasoning, and executive function, being severe enough to hamper activities of daily living. The clinical manifestations include behavior changes, dietary changes, loss of empathy, apathy, and executive function. Memory is intact earlier in the disease course.

Frontotemporal Dementia age of onset can be as early as the age of 40, with 54 being the average age of onset, and is often misdiagnosed in younger adults as a psychiatric issue and in older adults as Alzheimer’s. Older adults can start to see symptoms all the way into their 80s .

Classification

There are three types of FTD disorders:

1. Behavioural variant frontotemporal dementia (bvFTD)
2. Primary progressive aphasia (PPA) aka language variant frontotemporal dementia (lvFTD); non-fluent variant primary progressive aphasia (nfvPPA); semantic variant primary progressive aphasia (svPPA); logopaenic variant primary progressive aphasia (lvPPA)
3. Motor disorders: Amyotrophic lateral sclerosis (ALS); Corticobasal degeneration; Progressive supranuclear palsy (PSP)

Viewing

This 3 minute video is a good introduction.

Etiology

Tau in the cohesion of microtubules

FTLD is mainly a sporadic disease. A key role also is genetics, with approximately 40% of cases being familial in origin.

Scientists are beginning to understand the biological and genetic basis for the changes observed in brain cells that lead to FTD. The FTD group of diseases that can be characterised based on the type of glial and neuronal proteinaceous inclusions or underlying genetic mutation.

1. FTLD-tau: misfolded tau protein
2. FTLD-TDP: transactive response DNA binding protein 43
3. FTLD-FUS: fused in sarcoma protein (rare)

Head trauma and thyroid disease have been linked with the development of FTD with a 3.3-fold higher risk and 2.5-fold higher risk, respectively.

Epidemiology

FTD

• Is a common early-onset dementia (occurring in patients aged < 65 years).
• It has a prevalence rate of 3–26%, being one of the more common forms of dementia across all age groups
• Survival time is usually 7.5.years.

Symptoms

Symptoms of FTD are often misunderstood. Family members and friends may think that a person is misbehaving, leading to anger and conflict. It is important to understand that people with these disorders cannot control their behaviors and other symptoms and lack any awareness of their illness.

The three types of frontotemporal disorders (FTD present differently

1.Behavioral variant frontotemporal dementia: The most common FTD, bvFTD, involves changes in personality, behavior, and judgment. People with this disorder may have problems with cognition, but their memory may stay relatively intact. Symptoms can include:

• Problems planning and sequencing (thinking through which steps come first, second, and so on)
• Difficulty prioritizing tasks or activities
• Repeating the same activity or saying the same word over and over
• Acting impulsively or saying or doing inappropriate things without considering how others perceive the behavior
• Becoming disinterested in family or activities they used to care about
• Over time, language and/or movement problems may occur, and the person living with bvFTD will need more care and supervision.

2. Primary progressive aphasia PPA: Changes in the ability to communicate (use of language to speak, read, write, and understand what others are saying). eg difficulty using or understanding words (aphasia) and difficulty speaking properly (e.g., slurred speech). People with PPA may have one or both of these symptoms and may become mute or unable to speak. Many people with PPA develop symptoms of dementia. Problems with memory, reasoning, and judgment are not apparent at first but can develop over time. In addition, some people with PPA may experience significant behavioral changes, similar to those seen in bvFTD, as the disease progresses.

3. Motor disorders: Amyotrophic lateral sclerosis (ALS); Corticobasal degeneration; Progressive supranuclear palsy (PSP), rare neurological movement disorders associated with FTD, may affect thinking and language abilities. Note: The motor disorders are generally considered separate entities but, however, frequently have overlapping features of FTD

Diagnosis

FTD can be hard to diagnose because the symptoms are similar to those of other conditions. Many different tools are used to diagnose FTD. The diagnosis is made on a clinical basis, although genetic testing can confirm some specific subtypes .

The below may help with diagnosis

• Subjective and objective examination
• Personal and family medical history
• Laboratory tests to help rule out other conditions
• Genetic testing
• Conduct tests to assess memory, thinking, language skills, and physical functioning
• Order imaging of the brain

Treatment

So far, there is no cure for FTD and no way to slow down or prevent these diseases. However, there are ways to manage symptoms. A team of specialists eg doctors, physical, speech, and occupational therapists, familiar with these disorders can help guide treatment.

1. Non Drug Treatment

• Interventions for helping or adjusting behaviors.
• Speech Therapy to improve communication abilities.

2. Drug Treatment

• Antidepressant and antipsychotic medications for emotional and behavioral changes.
• Cholinesterase inhibitors for memory and attention.
• Antioxidant tocopherol (vitamin E) to counteract the damage in brain cells that causes PiD/ FTD and slow the worsening of the disease.
• Anti-inflammatory drugs and hormone replacement therapy are also being used by some specialists who treat PiD/ FTD as experimental treatments and are therefore not widely accepted.

Life with FTD - Home Care Program

It is recommended for People with FTD to remain physically, mentally and socially active as long as they can. In order to this, they need to:

• Daily physical activity such as walking for at least 20 minutes.
• Mental activity and stimulation such as puzzles, games, reading to slow the progression of the disease.
• Social interaction is recommended as a stimulating and enjoyable activity.
• Have balanced diet to maintain a healthy weight and prevent malnutrition and constipation.
• Smoking is prohibited for health and safety reasons.

The below 10 minute video gives a larger insight into FTD

References