Frontotemporal dementia (FTD) is a type of dementia that has often been called Pick’s disease. It encompasses a group of disorders that affect behavior, emotions, communication and cognition. Other names used for FTD include:
- frontotemporal degeneration
- frontal temporal dementia
- Pick's complex
- frontotemporal lobar degeneration
In FTD, the frontal and temporal anterior lobes of the brain are affected and shrink in size. FTD typically strikes relatively young (50s to 60s), but has been identified in people as young as 21 and as old as the late 80s. About 60% of cases of FTD are people between the ages of 45 and 64.
Arnold Pick first identified the abnormal tau protein collections in the brain (called Pick’s bodies) in 1892. Pick’s bodies are present in some types of FTD and can only be seen under a microscope during an autopsy.
Types of FTDFour disorders that fall into the FTD category include:
- Behavioral Variant Frontotemporal Dementia
As the name alludes to, behavioral variant FTD significantly impacts behavior, causing socially inappropriate interactions and emotions.
- Primary Progressive Aphasia
The primary component of this type of FTD is aphasia, which refers to an impairment in language ability. This can affect both the ability to communicate and understand.
- Progressive Supranuclear Palsy
Supranuclear palsy affects balance and movement, as well as cognitive abilities. A distinct symptom is impaired eye movement.
- Corticobasal Degeneration
Symptoms for corticobasal degeneration often appear as muscle weakness and tremors, and usually begin on only one side of the body. Problems with memory and behavior also develop as this disorder progresses.
Symptoms of FTD
- Behavior Changes
People with FTD often demonstrate socially inappropriate behavior, such as tactless comments, lack of insight or empathy, distractibility, increased interest in sex, or significant changes in food preferences. Others display poor hygiene, repetitive comments or behaviors, low energy and poor motivation. They may also have a flat or blunted affect, meaning that their faces display little or no expression of emotion, including sadness, joy, or anger.
- Communication Changes
FTD often affects the ability to communicate in both expressive speech (the ability to use words to express yourself) and receptive speech (the ability to understand speech). Individuals may have trouble finding the right word to say, speak very hesitantly and slowly, have a hard time reading and writing accurately, and not be able to form sentences in a way that makes sense.
- Movement Changes
FTD often affects the ability to control movement and other motor actions. Those with FTD may fall frequently or have unwanted arm and leg movements or shakiness.
Interestingly, a person's memory and understanding of the space around them often remain relatively intact, especially in the earlier stages.
How Do FTD and Alzheimer’s Differ?In Alzheimer’s, the typical initial symptoms are short-term memory impairment and difficulty learning something new. In FTD, the memory usually remains intact initially; early symptoms include difficulty with appropriate social interactions and emotions, as well as some language challenges.
FTD and Alzheimer’s also differ in how the brain is physically affected. FTD mainly affects the brain's frontal and temporal lobes; while Alzheimer’s tends to impact most areas of the brain.
FTD also targets younger individuals. The average age of onset for FTD is about 60 years old. While some people have early onset Alzheimer’s, the majority of patients are over 65 and many of those are well into their 70's or 80's.
What Causes FTD?The cause of FTD is not known. While the majority of cases of FTD appear to develop by chance, genetics does play a role in some cases. Approximately 10% of cases can be traced back to a change in a single gene. This gene mutation is directly inherited, meaning that if your mother or father has that specific gene for FTD, you have a 50% chance of developing FTD.
An additional 20% to 40% of people diagnosed with FTD have a familial connection where more than one relative over two or more generations has been diagnosed with FTD.
DiagnosisSimilar to diagnosing Alzheimer’s disease, there is no single test that can diagnose FTD. Patients typically undergo some imaging testing such as an MRI or a PET scan; cognitive testing to measure memory and language abilities; physical movement testing; possibly a spinal tap; and some blood tests. Diagnosis is made by gathering all of the results from these tests, ruling out other causes such as vitamin B12 deficiency or infections, and comparing your symptoms to other cases of FTD. It is important that a neurologist familiar with FTD and other types of dementia be involved in this evaluation since certain aspects of FTD mimic other disorders.
TreatmentsThere is no medication that targets this type of dementia, so the treatment goal is to control symptoms as much as possible. Physicians may prescribe medications that are often used for the movement problems in Parkinson's disease, including Sinemet. Sometimes the behaviors of FTD are addressed with antipsychotic medications if non-drug approaches are ineffective. Antidepressant medications, specifically selective serotonin reuptake inhibitors (SSRIs), have shown some benefit in treating some of the obsessive or compulsive behaviors of FTD. Some physicians will also prescribe medications usually given to Alzheimer’s patients, including cholinesterase inhibitors. Research, however, has not clearly shown these medications to be effective for FTD yet.
Occupational and physical therapy can also benefit patients by helping maintain or slow the deterioration of the motor and movement abilities, while speech therapy can sometimes assist with communication deficits.
Prevalence of Frontotemporal DementiaAbout 10% to 20% of all dementias are FTD, which translates to an estimated 50,000 to 60,000 Americans. FTD is one of the more common types of dementia in adults younger than age 65, and it is more common in men than women.
PrognosisThe prognosis of FTD is poor. Life expectancy ranges anywhere from from two to 20 years after diagnosis, depending on the speed of progression and the presence of other diseases. FTD does not cause death, but it makes fighting other illnesses and infections more difficult.
The Association for Frontotemporal Degeneration. Diagnosis. Accessed December 12, 2011. http://www.theaftd.org/frontotemporal-degeneration/diagnosis
The Association for Frontotemporal Degeneration. Frontotemporal Degeneration. Accessed December 12, 2011. http://www.theaftd.org/frontotemporal-degeneration/ftd-overview
The Association for Frontotemporal Degeneration. Genetics. Accessed December 12, 2011. http://www.theaftd.org/frontotemporal-degeneration/genetics
The Association for Frontotemporal Degeneration. What is FTD? Accessed December 12, 2011. http://www.theaftd.org/frontotemporal-degeneration
National Center for Biotechnology Information, U.S. National Library of Medicine. Pub Med Health. Pick’s Disease. Accessed December 10, 2011. http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001752/
University of California, San Francisco. Forms of Frontotemporal Dementia. Accessed December 11, 2011. http://memory.ucsf.edu/ftd/overview/ftd/forms/multiple
University of California, San Francisco. Hereditary FTD. Accessed December 11, 2011. http://memory.ucsf.edu/ftd/overview/biology/genetics/multiple/ftd
U.S. National Institutes of Health. National Institute on Aging. Types of Frontotemporal Disorders. Accessed December 12, 2011. http://www.nia.nih.gov/Alzheimers/Publications/FTLD/02.htm