Frontotemporal dementia is a term encompassing a group of dementias associated with progressive atrophy of the temporal lobe, frontal lobe, or both. Principal symptoms include behavioral disinhibition and personality changes, as well as deficits in language, both in speech production and word comprehension. The diagnosis can be made only after a thorough clinical and imaging workup.
Identified as the second most common type of early-onset dementia and responsible for approximately 10-20% of all dementias, frontotemporal dementia (FTD) is characterized by a progressive neuronal loss in the frontal and temporal lobes . FTD appears at a rate of 3-15 per 100,000 individuals between 55-65 years of age and affects both sexes almost equally . Several distinct clinical syndromes have been described in the literature      :
- Behavioral-variant frontotemporal dementia (bvFTD) - Considered as the most common form of FTD (presumably caused by genetic mutations), this subtype is responsible for about 50% of all cases and is distinguished by various changes in personality and behavior due to loss of neuronal circuits in the frontal lobe  . Disinhibition is the most prominent feature manifested as inappropriate social behavior (insensitive remarks to others, inclination toward violence, assault, excessive eating, hypersexual and sociopathic behavior), absence of empathy, lack of insight and awareness, abnormal behavioral patterns regarding their thoughts or habits, as well as a lack of personal hygiene and sphincter control are present in the majority of patients   . About 50% of bvFTD patients show either probable or possible signs of amyotrophic lateral sclerosis (ALS, which may develop together with all other forms of FTD, but much rarely as comapred to bvFTD). In that case, symptoms of motor neuron disease are present   .
- Semantic dementia (SD) - Progressive neuronal loss in the anterior temporal lobes is the main pathological entity described in SD, consequently leading to aphasia and loss in semantic memory (presenting as the inability to attach words with objects and an overall loss of vocabulary)   . As a result, patients interact by using nonspecific words and imprecise terms, while agnosia and prosopagnosia (inability to recognize visual objects or familiar faces, respectively), as well as behavioral disturbances seen in bvFTD, develop in later stages of the disease    .
- Progressive non-fluent aphasia (PNFA) - Agrammatism, apraxia (difficulties in speech initiation), dysarthria, and a slow speech full of errors are main characteristics of this type of FTD.
- Overlap syndromes - Some authors have confirmed overlapping of FTD and two clinical syndromes - corticobasal syndrome (CBD) and supranuclear palsy (in addition to ALS). Deficits in vertical gaze, postural instability, ophthalmoplegia and disinhibitory symptoms suggest an association of FTD with supranuclear palsy, whereas apraxia, rigidity, and myoclonus indicate CBD as the overlapping syndrome   .
- Abnormal Behavior
[…] and awareness, abnormal behavioral patterns regarding their thoughts or habits, as well as a lack of personal hygiene and sphincter control are present in the majority of patients. [symptoma.com]
Researchers looked at when the dementia symptoms began based on the earliest report from family members telling of persistently abnormal behavior. Survival was defined as from the time symptoms began until death. [psychcentral.com]
Some people with frontotemporal dementia become uninhibited, resulting in increasingly inappropriate behavior. They may speak rudely. Their interest in sex may increase abnormally. Behavior may become impulsive and compulsive. [merckmanuals.com]
- Inappropriate Sexual Behavior
Examples include shoplifting, encroaching on someone’s personal space, and inappropriate sexual behavior. Social skills like tact and empathy may be lost. They may lose interest in everything, or they may suddenly need to be active all the time. [dementiacarecentral.com]
- Motivation Decreased
[…] in motivation, decrease in energy, and generally compulsive behavior. [disabilitybenefitscenter.org]
- Disorganized Behavior
At the age of 58, the patient had a sudden onset of disorganized behavior and meaningless speech. Psychotropic drugs were effective for catatonic symptoms. [ncbi.nlm.nih.gov]
- Memory Impairment
The second patient presented with progressive memory impairment and marked personality changes after a transient ischaemic attack. [ncbi.nlm.nih.gov]
Also, deficits in verbal processing abilities and word retrieval may contribute to the decreased memory performance and to the impression of the caregiver that memory is impaired. [dx.doi.org]
Memory impairment is not an initial symptom, and yet those with PPA/FTD who are in the earlier stages may be perceived by others as having Alzheimer’s disease. [crisisprevention.com]
These possibilities include: Behavioral variant FTD – these patients have prominent, early changes in their behavior (such as being more impulsive or irritable), social interaction with others (kissing strangers, crude or explicit remarks), initiative [alzheimers.emory.edu]
[…] most common symptoms of bvFTD are behavioral or emotional challenges, including compulsively overeating, having an emotionally-detached demeanor, making socially inappropriate responses, and displaying hypersexual conversation and actions, along with irritability [alzheimers.about.com]
Personality changes can also involve increased irritability, anger and even verbal or physical outbursts toward others (usually the caregiver). [brain.northwestern.edu]
There are medications that can reduce agitation, irritability and/or depression. These treatments should be used to help improve quality of life. [alz.org]
Evaluation of patients in whom dementia of any type is suspected must start with a comprehensive history and a thorough physical examination, both being equally important. Physicians should suspect FTD if they detect language deficits and disinhibitory symptoms (which are often noticed by friends or family members, but not by the patients themselves), and if the patients are somewhat younger than the known age for the onset of dementia ( i.e.< 65 years of age). A complete neurological exam (to assess whether motor neuron disease is concomitantly present) and cognitive testing, an integral component in the assessment of dementia, provides vital clues to differentiate between various forms of FTD  . Imaging studies, however, are necessary to rule out other causes of such symptoms (eg. tumors), and magnetic resonance imaging (MRI) is the recommended method    . Atrophy of the frontal and temporal lobes are present, with the dorsolateral prefrontal cortex being involved in the majority of cases  . In addition, the anterior cingulate, orbitofrontal and frontoinsular cortices are commonly affected, often correlating with the extent of manifested symptoms . If findings on MRI are inconclusive, then single photon emission computed tomography (SPECT) or fluorodeoxyglucose positron emission tomography (FDG-PET) are recommended due to their ability to detect dysfunction of specific areas of the brain .
One subject stopped sertraline treatment because of diarrhea, while another stopped paroxetine treatment due to increased anxiety. [ncbi.nlm.nih.gov]
Care plans Before treatment starts, your current and future health and social care needs will be assessed, and a care plan drawn up. This is a way of ensuring you receive the right treatment for your needs. [nhs.uk]
Best prognosis tends to be in those with the semantic type, and survival may be as long as ten years or more. Worst prognosis is associated in the overlap syndrome with motor neurone disease, and there may only be 3-5 years between onset and death. [patient.info]
KEYWORDS: Amyotrophic lateral sclerosis; disease progression; frontotemporal dementia; incidence; primary progressive aphasia; prognosis [ncbi.nlm.nih.gov]
What are The Prognosis and Options for Treatment? FTD worsens over time and impairs the individual’s ability to live and function independently. [uofmhealth.org]
The case highlights the limitations of our diagnostic tools and the complex relationship between clinical symptoms, neuroimaging, and etiology. © The Author(s) 2014. [ncbi.nlm.nih.gov]
Neuroimaging (magnetic resonance imaging) usually demonstrates focal atrophy in addition to excluding other etiologies. [aafp.org]
At a minimum, these SNPs are known to be related, and others may also be Known genetic loci according to "The epidemiology of frontotemporal dementia" [ PMID 23611343 ]: Chromosome 9 open reading frame 72 ( C9orf72 ), chromosomal location 9p21.2, found [snpedia.com]
The clinic is conducting many research projects, including clinical trials and studies of day-to-day care, as well as epidemiologic, neuropsychiatric, neuropathological, and genetic investigations. [hopkinsmedicine.org]
We emphasized the key molecular actors in these processes, proposing them as novel FTD biomarkers that could be crucial for further epidemiological and molecular studies. [ncbi.nlm.nih.gov]
In the meeting the participants refreshed their knowledge in epidemiology, clinical diagnosis, neuropsychology, neuroimaging, neuropathology, genetics, cell biology, animal models and management for their daily practice in patient care. [icftd2016.de]
Discussion While the clinical presentation of frontotemporal dementia was described as early as the nineteenth century, recent advances in genetics have resulted in greater understanding of the pathophysiology of this disease. [racgp.org.au]
Recent advances in the understanding of FTD pathophysiology and genetics have led to the development of potentially disease-modifying therapies. [ncbi.nlm.nih.gov]
Currently, there is no specific treatment available to prevent disease progression. FTD treatment is based on symptomatic management, and most therapies lack quality evidence from randomized, placebo-controlled clinical trials. [ncbi.nlm.nih.gov]
Instead, risk factors for developing FTD include: Mutations in the MAPT and/or GRN genes of chromosome 17 A family history of FTD Treatments Like other varieties of degenerative dementia, there is no cure or treatment that can eradicate, prevent or stop [dementia.org]
Preventing or delaying dementia Recent research suggests that healthy lifestyle habits and mental stimulation may prevent dementia altogether or at least delay its onset. [helpguide.org]
Unfortunately, there is no way to prevent or reverse the damage caused by FTD yet, but medications and lifestyle changes can help relieve the symptoms. [memory.ucsf.edu]
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