FTD Flashcards
What is FTD?
A group of disorders marked by progressive degeneration of the frontal and temporal lobes, affecting personality, behavior, language, and sometimes movement.
*It is a leading type of early-onset dementia
What age group is most commonly diagnosed with FTD?
60% are diagnosed between ages 45–64.
What makes diagnosing FTD difficult?
Its symptoms often resemble psychiatric disorders, especially in behavioral variant cases.
What happens in FTD and why?
- The frontal and temporal lobes shrink with symptoms varying depending on the area affected
- 1/3rd of cases are associated with genetics but there are no known risk factors for FTD
- No treatments exist, although medications can reduce behavioral symptoms
FTD Progression
- Primary symptoms are often speech and movement
- Continually progresses, however, rate of decline varies between people
- People often show progressive muscle weakness and coordination problems
- Average life expectancy is 7-13 years after the start of symptoms
What are the risk factors of FTD
- The only known risk factor for FTD is family history
- At least 8 genes - including some with very rare mutations - are known to cause FTD
- The behavioral variant of FTD is most often inherited; semantic FTD is only rarely inherited
Causes of FTD
- Loss of neurons and abnormal amounts of proteins called tau and TDP-43
- Tau: protein that is normally present and stabilizes neurons. Forms tangles inside neurons and leads to destruction of brain cells
- TDP-43: involved with gene expression and RNA/DNA processing and metabolism
- Become mislocated from nucleus to cytoplasm and forms inclusions interfering with cell functions
Difference between tau in FTD and AD
In FTD, tau pathology is one of several possible underlying mechanisms and tends to be more variable and focal. In contrast, AD always involves tau (as neurofibrillary tangles) and amyloid-beta plaques, forming the classic pathological signature of the disease.
Behavioral Variant FTD (BvFTD)
The most common variant of FTD and includes changes in personality, behavior, and judgment
- Lack of motivation
- Disinterested in activities / people
- Disinhibition / impulsivity
- Problems planning
Problems with cognition may present but memory stays intact
Over time language and or movement problems may occur
Brain Changes in BvFTD
- Typical changes include atrophy of frontal lobes and anterior temporal (although temporal tends to be a to a lesser degree)
- Degree can be asymmetric (typically worse on right)
Language Variant FTD (PPA)
- Changes in ability to communicate (speak, read, write, and understand)
- Language dysfunction is the main symptom for the first 2 years of the illness
- Deficits include language production, object naming, syntax, or word comprehension
Two forms of PPA
- Non-fluent PPA - speaking is hesitant, labored, or ungrammatical
- Semantic variant – lose ability to understand or formulate words
Brain Changes: non-fluent PPA (nfvPPA)
- Atrophy is more variable, typically in posterior frontal, and temporal lobe
- Generally left hemisphere is thought to be most affected but not universal
Brain Changes: semantic variant PPA (svPPA)
- Left hemisphere (anterior) temporal lobe atrophy
- More anterior than posterior
- Includes many areas including, amygdala, hippocampus, fusiform gyrus
Motor Disturbances
- About 1 in 10 people with FTD will also develop a motor neuron disease
- Three main movement/muscle function disorders in both types of FTD:
1. Amyotrophic lateral sclerosis (ALS)
2. Corticobasal syndrome
3. Progressive supranuclear palsy (PSP)
Amyotrophic lateral sclerosis (ALS):
muscle weakness/wasting
- These changes are the same observed in people with ALS
- Muscle weakness and atrophy
- Muscle jerks / wiggling in muscles
- Difficulty grasping a pen or cup
- Difficulty lifting arms above the head
- Clumsiness when completing find motor movements with hands or fingers
Corticobasal syndrome:
arms and legs become uncoordinated and/or stiff
- Most common symptom is apraxia – inability to use hands or arms to perform movements
- Muscle rigidity and difficulty swallowing are also common
- Symptoms often appear on one side of the body then progress to the other side
- Can develop the motor symptoms after language difficulties and orientation objects in space
- Not everyone with corticobasal syndrome has problems with memory, cognition, language, or behavior
Palsy (PSP):
muscle stiffness, difficulty walking, changes in posture, with changes in eye movements also observed
- Typically move more slowly
- Experience unexplained falls
- Lose facial expression
- Body stiffness observed particularly in the next and upper body
- Eye movement tend to involved difficulty looking down
Diagnostic Criteria - Frontotemporal Dementia FTD
● Insidious onset
● Gradual progression
Exclusion criteria:
➢ Deficits better explained by other medical disorders
➢ Deficits better explained by a psychiatric disorder
➢ Biomarkers strongly suggest other neurodegenerative process
Diagnostic Criteria - Behavioral Variant (BV-FTD)
At least three:
● Behavioral disinhibition
● Apathy or inertia
● Loss of sympathy or empathy
● Stereotypical, compulsive, or perseverative behavior
● Hyperorality or dietary changes
● Executive deficits with relative sparing of visuospatial skills and memory
Diagnostic Criteria - Language Variant (PPA)
● Prominent language impairment
● Language deficits impair daily functioning
● Aphasia is the most prominent initial-phase deficit
Exclusion criteria:
➢ Prominent early deficits in episodic memory, visual memory, or visual perception skills
➢ Prominent early behavior disturbances
Diagnostic Criteria - Semantic Variant (SV-PPA)
● Impaired confrontation naming
● Impaired single-word comprehension
● At least three: impaired object knowledge, surface dyslexia or dysphasia, spared repetition and
speech production
Diagnostic Criteria - Non-Fluent Variant (NFV-PPA)
● At least one:
➢ Agrammatism in production
➢ Apraxia of speech
● At least two:
➢ Impaired comprehension of complex sentences
➢ Spared single-word comprehension
➢ Spared object knowledge
Behavioral Variant FTD (BV-FTD) - Key Features
- Profound personality changes: disinhibition, impulsivity, and inappropriate behaviors (e.g., sexual remarks, lack of embarrassment).
- Loss of empathy: individuals may seem emotionally cold or indifferent.
- Emotional blunting: apathy, lack of motivation, and depression are common.
- Poor judgment: including risky behaviors or financial decisions.
- Compulsive behaviors: motor stereotypies (e.g., pacing, clapping) and repetitive routines.
- Eating changes: overeating, preference for sweet foods, hyperorality (putting non-food items in the mouth), and loss of food selectivity.
- Reduced pain sensitivity and possible parkinsonism or motor neuron disease in some cases.
- Executive dysfunction is prominent early on.
🟢 Takeaway: BV-FTD is dominated by social, emotional, and behavioral symptoms with early loss of insight and self-awareness. It is often mistaken for a psychiatric disorder due to its dramatic personality shifts.
Semantic Variant PPA (SV-PPA) - Key Features
- Loss of word meaning: difficulty naming objects (anomia), understanding words, or recognizing people or categories.
- Prosopagnosia: inability to recognize familiar faces, even close family members (see definition below).
- Compulsive or ritualistic behavior is common (e.g., collecting objects, rigid routines).
- May show emotional detachment, irritability, or blunted empathy, but usually without dramatic disinhibition.
- Increased selectivity in eating (e.g., only wanting specific foods) and food fads may emerge.
- Sensory hypersensitivity (especially to pain or temperature) can be present.
🟢 Takeaway: SV-PPA is a language and semantic memory disorder that can also present with compulsive behaviors and social-emotional flattening. Personality changes tend to be less overt than in BV-FTD.
Non-Fluent Variant PPA (NFV-PPA) - Key Features
- Agrammatism: difficulty constructing sentences; speech becomes effortful and telegraphic.
- Apraxia of speech: difficulty coordinating mouth movements to produce words.
- Comprehension of complex sentences declines, although single-word understanding is often intact.
- Emotionally, may present with irritability or anxiety, but social behavior is generally preserved.
- Some individuals develop motor symptoms, such as those seen in Progressive Supranuclear Palsy (PSP) or Corticobasal Syndrome (CBS).
- Eating behavior, repetitive behaviors, and neuropsychiatric symptoms are rare.
🟢 Takeaway: NFV-PPA is a speech production disorder with minimal behavioral or emotional disturbance. Some motor decline may appear over time.
