This article will discuss the following topics:
- What is Frontotemporal Dementia (FTD)?
- FTD, Pick’s Disease, and Alzheimer’s
- Alzheimer’s and types of Frontotemporal Dementia
- Symptoms of frontotemporal Dementia
- Causes of Frontotemporal Dementia
- Diagnosis of Frontotemporal Dementia
- Treatment and Management of Frontotemporal Dementia
- Final Thoughts
Frontotemporal dementia is a group of related conditions resulting from the progressive degeneration of the frontal and temporal lobes of the brain. FTD is most commonly referred to as frontotemporal dementia (FTD), fronto-temporal lobar degeneration (FTLD), or Pick’s Disease. Damage in the frontal and temporal areas of the brain causes impairment and changes in personality, behavior, language, and muscle or motor function. FTD usually occurs earlier in life (mid-40s to early-60s), and causes a steady, gradual decline in the ability to complete Activities of Daily Living (ADLs).
The Frontal Lobes of the brain are associated with functions in planning, reasoning, judgment, and problem-solving. Changes in the frontal lobe are generally associated with behavioral symptoms. The Temporal Lobes of the brain are involved with the processing of hearing, speech, emotion, and memory. Changes in the temporal lobes are linked to language and emotional disorders. As a result, different symptoms are present in each FTD patient as various parts of the frontal and temporal lobes are affected.
Behavioral and personality symptoms consist of problems with executive function such as planning, multitasking, prioritizing, sequencing, and self-monitoring and correcting behaviors. Changes in behavior and personality may lead to a decreased concern for social norms, other people, and an overall lack of insight into one’s own behaviors. There are key words that describe some specific FTD behavioral symptoms:
- Perseveration: the tendency to repeat the same activity or word
- Social Disinhibition: acting impulsively without concern over how others may perceive the behavior
- Compulsive Behavior: the compulsive eating of starchy foods such as bread and cookies
- Utilization Behavior: difficulty in resisting impulses to use or touch objects
Emotional symptoms are noticeable through social-interpersonal changes such as difficulty reading and understanding social signs, facial expressions, and body language.
Individuals may also lack empathy, which may make them seem as though they are indifferent, selfish or uncaring. For example, if a close friend is in a terrible accident, an individual with FTD may not display any emotional reactions. Emotions may seem completely disconnected from a situation or expressed at the wrong time, or in the wrong context. An individual may also lack apathy, and may not have the drive, initiative, or interest in doing certain things. Apathy is often incorrectly confused with depression.
As mentioned earlier, the temporal lobes are associated with language and emotion. Two distinct language symptoms are prevalent in those with FTD: aphasia and dysarthria.
- Aphasia is a language disorder that is characterized by the inability to use and understand words. People with aphasia, however, may still be able to pronounce words in what may be comprehensive, but lack clarity or proper understanding.
- Dysarthria is a language disorder that impairs the physical ability to speak properly, causing pronunciation issues such as slurring words. Even though the ability to speak may be impaired, the message or point that an individual may be trying to convey remains intact.
Language problems get worse over time and progress at a quicker rate than other skills such as thinking or social behavior.
Changes in the frontal lobe can initiate two main motor symptoms in FTD patients.
- Dystonia is the abnormal posture of body parts such as the hands and the feet. For example, an individual’s hand can be bent or stiff and not be used in an activity that would normally require the use of two hands.
- Apraxia is a gait disorder that causes abnormalities in walking, frequent falls, tremors, and clumsiness. Individuals with Apraxia also have an inability to do common motions such as buttoning up a shirt or unzipping something, regardless of the normal strength that an individual may have. People may also experience neuromuscular weakness characterized by severe weakness and cramps in muscles.
Effects of FTD Symptoms
- Difficulty in reasoning, judgment, organization, and planning can cause patients to be gullible and fall prey to scams
- Lack of judgement may lead to criminal behavior- shoplifting, indecent exposure, running stop lights, poor financial judgement, impulsive buying
- At the extreme, impulsivity can be self-destructive, as when patients try to get out of moving cars
Frontotemporal disorders are grouped into three sub-types based on the observed symptoms in the patient.
Progressive Behavior/ Personality Decline
- Behavior Variant Frontotemporal Dementia (bvFTD)
- Temporal/Frontal Variant FTD (tvFTD, fvFTD)
- Pick’s Disease
- Primary Progressive Aphasia (PPA)
- Progressive Nonfluent Aphasia
- Semantic Dementia
- Corticobasal Syndrome (CBS)
- Progressive Supranuclear Palsy (PSP)
- FTD with Parkinsonism
- FTD with Amyotrophic Lateral Sclerosis (FTD-ALS)
Only rough estimates are available, but there may be 50,000 to 60,000 people with bvFTD and PPA in the United States; the majority of whom are between 45 and 65 years of age.
Initially, in the late 19th century (1892), Behavioral Variant Frontotemporal Dementia (bvFTD) was known as Pick’s disease, after Dr. Arnold Pick who described a patient with language symptoms. The term Pick’s Disease is now used to describe abnormal aggregates and collections of the protein Tau, coined “Pick Bodies.” Some patients with bvFTD may have Pick bodies in their brain, while others do not.
Frontotemporal Dementia refers to a group of disorders that are caused by progressive nerve cell loss and shrinkage in two regions of the brain: the frontal lobe (manage emotional responses) and temporal lobes (essential for memory, language, and emotions). Symptoms thus vary between individuals based on which parts of the brain are affected, and the stage of disease progression. This variability causes FTD to often be misdiagnosed as a psychiatric problem or even Alzheimer’s disease.
FTD accounts for 20% of young-onset dementia cases.
As expressed above, FTD refers to a family of brain diseases that have similar molecular etiologies. There is not a single cause of FTD, but the two most common causes of FTD are:
- Brain disorders involving the Tau protein
- Brain disorders involving the TDP-43 protein
Abnormal amounts and forms of the Tau and TDP-43 proteins have been identified in autopsies of brains with FTD. Mutations in genes that control the expression and formation of these proteins, for reasons not yet fully understood, damage neurons in specific regions of the brain. About 15 to 40 percent of patients with frontotemporal dementia have the disease because of a genetic abnormality. Individuals with a family history of FTD will more than likely have a genetic form of FTD than those without a family history of FTD.
Mutations in the Tau gene form tangles inside the neurons and eventually lead to the destruction of brain cells due to abnormalities in the Tau protein. Those with a mutation in the Tau gene will most likely develop FTD (most likely bvFTD), although the age at which the onset of symptoms develops cannot be predicted.
A mutation in the PGRN gene can lead to a lower production of the protein progranulin and, as a result, cause abnormalities in the function and expression of the TDP-43 protein. An abnormal build up of the TDP-43 protein forms aggregates that interfere with cell functions and ultimately cause cell death in the brain. A mutation in the PGRN Gene can cause many different symptoms and makes one susceptible to any of the forms of FTD.
A mutation in the VCP, CHMP2B, TARDBP, and FUS genes can lead to very rare familial types of FTD. A rare mutation in the C9ORF72 gene has been observed to be the most common genetic abnormality in familial FTD and familial ALS. A mutation in this gene can cause the development of FTD, ALS, or even both in some individuals.
Frontotemporal dementia is characterized by three distinct types:
Behavioral Variant Frontotemporal Dementia (bvFTD) is the most common type of FTD. This condition is known for its impact on changes in personality, behavior, and interpersonal relationships. Although bvFTD frequently occurs in individuals in their 50’s and 60’s, it can also develop in individuals in as early as in their 20’s, and as late as in their 80’s.
In bvFTD, the nerve cell loss is most prominent in areas that control foresight, conduct, empathy, and judgment, along with other abilities as well. As a result, personality changes in individuals are inevitable and involuntary. While the memory stays intact, some of the main early symptoms consists of apathy or reduced initiative, inappropriate and impulsive behaviors, excessive emotions, or little to no emotions at all.
Primary Progressive Aphasia (PPA) is known for its impact on speech, language skills, and ability to comprehend and write. PPA usually develops mid-life before the age of 65, but can also infrequently occur in later life. There are two forms of PPA that have different and distinct symptoms:
Semantic Variant PPA is when patients lose their ability to understand or formulate words in a spoken sentence. The other form is Non-Fluent or Agrammatic Variant PP which makes a patient’s speaking ability ostensibly hesitant, labored, and ungrammatical or confused.
There are three main disorders that produce changes in motor and muscle functions with or without behavior (bvFTD) or language (PPA) difficulties.
- Amyotrophic Lateral Sclerosis (ALS) is a disorder that causes muscles to weaken or waste. ALS is a motor neuron disease also known as Lou Gehrig’s disease. In approx ¼ of ALS patients, the disease is associated with subtle cognitive deficits, and 3-5% of ALS patients are diagnosed with Fontotemporal Dementia (FTD).
- Corticobasal Syndrome is a disorder that can cause the arms and legs to become uncoordinated or stiff, thus inhibiting motion.
- Progressive Supranuclear Palsy (PSP) is a disorder that can cause muscle stiffness, difficulty walking, and marked changes in posture; it is also known to affect eye movements.
Individuals will show signs of progressive muscle weakness and coordination problems for many years. As a result, patients can become wheelchair-bound or bed-bound. In addition, these muscle challenges can also cause problems with chewing, swallowing, controlling bladder and bowels, and problems with moving about in general. Eventually, individuals will come to their end of life conditions owing to the drastic physical changes that can cause urinary tract, skin, and lung infections.
Both bvFTD and PPA are far less common than Alzheimer’s Disease in those over the age of 65. However, in the 45 to 65 age range, bvFTD and PPA are nearly as common as younger-onset Alzheimer’s.
There is no a single test that can lead to a definitive FTD diagnosis. There are, however, two processes that can help lead to a diagnosis:
- Confirmation through a genetic test in familial cases.
- Conducting a brain autopsy once an individual is deceased
An FTD diagnosis remains in the realm of a “probability” rather than a “definitively”. With a probable diagnosis, one of three doctors (a psychiatrist, psychologist, or neurologist) will usually collect information about the individual and perform appropriate tests. The doctor will compile individual and family medical histories, record symptoms, order testing if necessary to uncover genetic mutations, order blood tests, perform a physical exam, use brain imaging to look for changes in the temporal and frontal lobes, and conduct a neuropsychological evaluation to assess cognitive functions. Despite all those measures, FTD may still be difficult to diagnose because its symptoms are very similar to other conditions.
Like Alzheimer’s and most other types of dementia, there are unfortunately no specific treatments that can cure any of the frontotemporal dementia types. Unlike other types of dementia, there are also no treatments to slow down the progression of FTD. To make matters worse, due to the difficulty of the diagnosis, individuals may go a long time before they get any help in managing the harsher aspects of their symptoms. With the correct medications, however, behavioral symptoms like irritability, depression, and agitation can be better managed.
Even though medications can be taken to help improve the patient’s quality of life, FTD inevitably gets worse over time. It is important to remember that each patient with FTD is different, and the speed of decline and how the symptoms are managed will thus differ. Because FTD is unique in each individual, the signs and symptoms may are different and thus make a proper diagnosis all the more complex.
Changes in the patient’s behavior are often the first noticeable symptoms in bvFTD, the most common type of FTD.
Although Alzheimer’s Disease and FTD have few symptoms in common, the symptoms cannot be treated with the same pharmacological agents. This is because the cholinergic systems, which relate to nerve cells, are not affected in FTD as they are in Alzheimer’s. Moreover, the disinhibition and compulsive behaviors in an individual with FTD can be controlled by selective Serotonin Reuptake Inhibitors (SSRIs). Symptoms of FTD progress at a rapid, steady rate. Individuals that suffer from frontotemporal dementia can survive between two-to-fifteen years and will most likely need 24-hour assistance with their Activities of Daily Living in their later years.
It is important to learn how to live with a person who has FTD. The person that everyone once knew may seem like no longer there. Learning, understanding, and befriending this “new person” is therefore something everyone should try to accomplish. It is best to know how to respond to their actions since a proper response can reduce frustration in all the individuals involved, and it can help cope with the challenges of caring for an individual with FTD.
Managing symptoms in patients with FTD involve several approaches. First, one must remember to always be sensitive and understanding when dealing with a patient with FTD. It is possible that they may say something that is hurtful or unforgivable, but that has to be taken in light of what the disease entails. Another approach is to limit choices and offer specific ways to go about things. Do not ask what shirt they want to wear to the gathering, although having a couple of options may not cause them added stress. Open-ended questions should also be avoided as the individual needs specific pathways for dealing with things. FTD patients also do better when they have a regular routine with perhaps an occasional change in the environment. A regular schedule is less confusing, helps them sleep better, and gives them something to look forward to without the uncertainty of not knowing what to expect.