ABC’s of FTLD
What is Frontotemporal lobar degeneration?
Frontotemporal lobar degeneration or frontotemporal dementia is an umbrella term for a group of disorders that primarily affect the frontal and temporal lobes of the brain- the areas generally associated with personality and behavior.
Frontotemporal dementia is a progressive, degenerative brain disease. In people under age 60, FTD is the most common cause of dementia and affects as many people as Alzheimer’s disease in the 45-64 age group. Approximately 40% of patients with FTD have a family history of a similar dementia, while 60% of people with FTD develop it without any known cause.
The term FTD as a “general term” can also refer to
- Pick’s Disease
- Frontotemporal lobar degeneration
- Progressive nonfluent aphasia
- Semantic dementia
Dementia is a problem of the elderly, right? Generally that’s true. But there is one form of the disease that can strike people when they are very young, in their 20′s or even their teens. It’s called Frontotemporal Dementia, or FTD. And while rare, it devastates lives by rapidly turning young, vital people into those who need constant care.
Frontotemporal lobar degeneration (FTLD): The term that describes the specific pathological diseases that result in FTD syndromes. Subtyping is based on the specific proteins found within the neuronal inclusions
Types or Variants of FTLD
Behavioral variant (bvFTD)
Semantic dementia (SD)
Progressive nonfluent aphasia (PNFA)
FTD with Motor Neuron Disease (MND)
Behavioral variant FTD (bvFTD)
Behavioral variant frontotemporal dementia (bvFTD) has also been referred to as “frontal variant FTD” (fvFTD) or “Pick’s disease.” Approximately 60% of people with any form of FTD have bvFTD. By definition, this form of FTD affects social skills, emotions, personal conduct, and self-awareness. Deficits in these functions most often reflect damage to specific regions within the frontal and temporal lobes. With damage to these areas, people may show mood and behavior changes including stubbornness, emotional coldness or distance, apathy and selfishness. Unlike Alzheimer’s disease, which affects a different area of the brain, many people with bvFTD don’t show any confusion or forgetfulness about where they are or what day it is, at least at first.
Semantic dementia, which has also been called “temporal variant FTD,” accounts for 20% of FTD cases. Language difficulty, the predominant complaint of people with SD, is due to the disease damaging the left temporal lobe, an area critical for assigning meaning to words. The language deficit is not in producing speech but is a loss of the meaning, or semantics, of words. At first, you might notice someone substituting a word like “thingy” for more unusual words, but eventually a person with SD will lose the meaning of more common words as well. For example, early in the illness a patient might lose the word for a falcon, later-on forget the word for a chicken, then call all winged creatures “bird” and eventually call all animals “things.” Not only do they lose the ability to recall the word, but the concept of these words is also lost. “What is a bird?” might be a typical response for a patient with advanced SD. Reading and spelling usually decline as well, but the person may still be able to do arithmetic and use numbers, shapes or colors well. Names of people, even good friends, can become quite difficult for people with SD. Like the behavioral variant, memory, an understanding of where they are, and sense of day and time tend to function as before. Muscle control for daily life and activities tends to remain good until late in the disease. Some of these skills may seem worse than they actually are because of the language difficulty people with SD have when they try to express themselves.
When SD starts in the right temporal lobe, people in the early stages have more trouble remembering the faces of friends and familiar people. Additionally, these people show profound deficits in understanding the emotions of others. The loss of empathy is an early, and often initial, symptom of patients with this right-sided form of SD. Eventually people with right-sided onset progress to the left side and then develop the classical language features of SD. Similarly, left-sided cases progress to involve the right temporal lobe and then the person experiences difficulty recognizing faces, foods, animals and emotion. SD patients eventually develop classical bvFTD behaviors including disinhibition, apathy, loss of empathy and diminished insight. The time from diagnosis to the end is longer than for those with bvFTD, typically taking about six years. At least at first.
Progressive non-fluent aphasia
PNFA accounts for only about 20% of all people with FTD. Unlike semantic dementia where the person maintains the ability to speak but loses the meaning of the word, people with PNFA have difficulty producing language fluently even though they still know the meaning of the words they are trying to say. The person may talk slowly, having trouble saying the words, and have great trouble with the telephone, talking within groups of people or understanding complex sentences. In recent years it has become apparent that many patients with PNFA go on to develop severe Parkinsonian symptoms that overlap with progressive supranuclear palsy (PSP) andcorticobasal degeneration (CBD) such as an inability to move the eyes side-to-side, muscle rigidity in the arms and legs, falls, and weakness in the muscles around the throat.
FTD with motor neuron disease
Approximately 15% of patients with FTD also develop motor neuron disease (FTD-MND). Most often, this combination occurs in patients with bvFTD, and only rarely does MND arise in patients with SD or PNFA. MND affects motor nerve cells in the spinal cord, the brain stem (which sits on top of the spinal cord), and the cerebral cortex. Because the brainstem was once referred to as the “bulb”, you may hear some MND symptoms described as “bulbar symptoms”. The most common type of MND is amyotrophic lateral sclerosis(ALS), also called Lou Gehrig’s disease, which can occur as a purely motor disorder. More often, however, patients with ALS also have behavioral or cognitive problems similar to those seen in FTD. MND symptoms include slurring of speech, difficulty swallowing, choking, limb weakness or muscle wasting. In patients with FTD-MND, there is often (but not always) a family history of the disease, and scientists are getting closer to identifying gene mutations that cause the illness.
ABC’S OF FTD
Source: University of California, San Francisco, Department of Neurology, Memory and Aging Center
A – Affect (Mood)
B – Behavior
Dis-inhibition (sexual, social)
C – Cognition
Loss of Abstract Reasoning
Loss of Insight
Loss of Judgement
Visuospatial Dysfunction (getting lost)
Problems with ADLs (Activities of Daily Living: dressing, eating, bathing, taking medications, operating microwaves, remote controls, etc).
ABCs of FTD by Paul E. Schulz, M.D.
Note: Not every FTLD sufferer will exhibit all the following symptoms. This is meant to serve only as a guideline.
Slight mood changes
Difficulty doing math in head
Difficulty finding words
Stopping in mid-sentence
More reclusive, paranoid
More conscious about spending money
Stops favorite activities
Speech harder to understand
Problems with work
More aggressive behaviors
More sexually active
Artistic abilities may change
Repeats familiar phrases
Flips words around
Rarely smiles, joyless
Not able to handle social situations
Little concern about personal hygiene
Rapid mood changes
Failure to show concern
Problems with balance
Less writing, signature change
Artistic abilities fade
Medical Terms in FTD
aphasia: A loss of the ability to produce and/or understand language due to injury to brain areas specialized for these functions.
atrophy: Wasting away or shrinking. Neuronal atrophy is wasting away of neurons, a decrease in neuronal density.
cellular inclusion: Any small intracellular body found within a cell.
dementia: A deterioration of intellectual faculties, such as memory, concentration and judgment, resulting from an organic disease or disorder of the brain. It is sometimes accompanied by emotional disturbance and personality changes.
frontal lobe: The part of each hemisphere of the brain located behind the forehead that serves to regulate and mediate the higher intellectual functions. The frontal lobes have intricate connections to other areas of the brain. In the frontal lobes, we meld emotions, cognition, error detection, volition, a sense of self, and more to create our social brain.
frontal variant FTD (fvFTD): an older term for behavioral variant FTD (bvFTD)
frontotemporal dementia (FTD): The umbrella term for the clinical syndromes of behavioral variant frontotemporal dementia (bvFTD), semantic dementia (SD) and progressive non-fluent aphasia (PNFA). These syndromes share involvement of the frontal and temporal lobes of the brain. This term is sometimes used to refer specifically to bvFTD.
frontotemporal lobar degeneration (FTLD): the term that describes the specific pathological diseases that result in FTD syndromes. Subtyping is based on the specific proteins found within neuronal inclusions.
neuronal inclusion: Any small intracellular body found within a neuron (nerve or brain cell).
Pick bodies: A specific type of cellular inclusion made up of the protein tau and seen in some people with FTD.
Pick’s disease: another name for behavioral variant frontotemporal dementia (bvFTD), which has also been called frontotemporal dementia (FTD) and frontal variant frontotemporal dementia (fvFTD)
PPA (primary progressive aphasia): A neurodegenerative disease marked by the progressive decline of language functions. PPA has now been split into three subgroups: semantic dementia (SD), progressive nonfluent aphasia (PNFA) and logopenic progressive aphasia (LPA).
progressive non-fluent aphasia (PNFA): one of the language variants of frontotemporal dementia (FTD)
semantic dementia (SD): one of the language variants of frontotemporal dementia (FTD)
semantic paraphasia: The substitution of a word that is closely related to the target word, as in “cat” for “dog.”
tau: A protein in the body that aids in the cellular structure (cytoskeleton) and cellular transportation.
temporal lobe: The lobe of the cerebral hemisphere located down on the side of the brain near the ears. The temporal lobe contains the auditory cortex which is responsible for hearing, language comprehension and memory.
temporal variant frontotemporal dementia (tvFTD): an older term for the language variants of FTD (SD and PNFA)