Frontotemporal Dementia (FTD)

About
Symptoms
Diagnosis

Causes & risks
Treatments

About frontotemporal dementia

The cell damage caused by frontotemporal dementia leads to tissue shrinkage and reduced function in the brain's frontal and temporal lobes, which control planning and judgment; emotions, speaking and understanding speech; and certain types of movement.

FTD includes a range of specific disorders with different core symptoms. But there's significant symptom overlap, especially as these disorders progress. The disorders grouped under FTD fall into three broad categories (discussed below). Scientists have identified a range of microscopic brain abnormalities implicated in FTD. The overall term for the brain cell damage and tissue shrinkage associated with FTD is frontotemporal lobar degeneration.

FTD used to be called Pick's disease after Arnold Pick, a physician who in 1892 first described a patient with distinct symptoms affecting language. Some doctors still use the term "Pick's disease." Other terms you may see used to describe FTD include frontotemporal disorders, frontotemporal degeneration and frontal lobe disorders.

FTD was once considered rare, but it's now thought to account for up to 10 to 15 percent of all dementia cases. It's still believed to be less common than Alzheimer's disease, vascular dementia and Lewy body dementia.

In those younger than age 65, FTD may account for up to 20 to 50 percent of dementia cases. People usually develop FTD in their 50s or early 60s, making the disorder relatively more common in this younger age group. Sign up for our enews to receive updates about Alzheimer’s and dementia care and research.

Learn more: Frontotemporal Disorders Guide from the National Institute on Aging (NIA) (PDF)

Symptoms

Experts group frontotemporal dementia into three main categories. Initially, these groups tend to cause different core symptoms based on the first parts of the brain's frontal or temporal lobes they affect. But there's increasing overlap in symptoms as these disorders progress.

Symptoms related tothe three types of FTD include:

• Behavioral variant frontotemporal dementia (bvFTD) takes its greatest toll on personality and behavior. It may begin with subtle changes that may be mistaken for depression. As bvFTD progresses people often develop disinhibition, a striking loss of restraint in personal relations and social life.
  
  
• Primary progressive aphasia (PPA) affects language skills in early stages, but often also affects behavior as it advances. The two chief forms of PPA have somewhat different symptoms:
• In semantic dementia, people speak easily, but their words convey less and less meaning. They tend to use broad general terms, such as "animal" when they mean "cat." Language comprehension also declines.
• In progressive nonfluent aphasia, people lose their ability to generate words easily, and their speech becomes halting, "tongue-tied" and ungrammatical. Ability to read and write also may be impaired.
  
  
• FTD movement disorders affect certain involuntary, automatic muscle functions. These disorders also may impair language and behavior. The two primary FTD movement disorders are:
• Corticobasal degeneration (CBD), which causes shakiness, lack of coordination, and muscle rigidity and spasms.
• Progressive supranuclear palsy (PSP), which causes walking and balance problems, frequent falls and muscle stiffness, especially in the neck and upper body. It also affects eye movements.

Diagnosis

There is no single test — or any combination of tests — that can conclusively diagnose frontotemporal dementia. FTD is a "clinical" diagnosis representing a doctor's best professional judgment about the reason for a person's symptoms. Magnetic resonance imaging (MRI) often plays a key role in diagnosis because it can detect shrinkage in the brain's frontal and temporal lobes, which is  a hallmark of FTD.

In some cases, it may be hard to distinguish FTD from Alzheimer's disease. In the future, tests to detect specific protein abnormalities linked to Alzheimer's and FTD may help clarify the diagnosis in difficult cases.

Key Differences Between FTD and Alzheimer's Age at diagnosis may be an important clue. Most people with FTD are diagnosed in their 50s and early 60s. Only about 10 percent are diagnosed after age 70. Alzheimer's, on the other hand, grows more common with increasing age. Memory loss tends to be a more prominent symptom in early Alzheimer's than in early FTD, although advanced FTD often causes memory loss in addition to its more characteristic effects on behavior and language. Behavior changes are often the first noticeable symptoms in bvFTD, the most common form of FTD. Behavior changes are also common as Alzheimer's progresses, but they tend to occur later in the disease. Problems with spatial orientation — for example, getting lost in familiar places — are more common in Alzheimer's than in FTD. Problems with speech. Although people with Alzheimer's may have trouble thinking of the right word or remembering names, they tend to have less difficulty making sense when they speak, understanding the speech of others, or reading than those with FTD. Hallucinations and delusions are relatively common as Alzheimer's progresses, but relatively uncommon in FTD.

Causes and risks

Researchers have identified abnormal deposits of several proteins inside the brain cells of those who died with frontotemporal dementia. Scientists have not yet learned what causes these protein abnormalities or solved the mystery of why the damage associated with FTD targets the brain's frontal and temporal lobes.

The only known risk factor for FTD is a family history of the disease. Scientists have found several genes linked to FTD.

Recent research suggests a possible connection between FTD and Lou Gehrig's disease, also known as amyotrophic lateral sclerosis (ALS) and motor neuron disease. Although ALS primarily affects nerves controlling voluntary movement, many people with ALS also develop symptoms affecting their behavior or language, and some people with FTD develop ALS.

Help is available The Association for Frontotemporal Degeneration (AFTD) is a nonprofit organization that provides information, education and support to those affected by FTD and their caregivers. Call AFTD at 866.507.7222. The Alzheimer's Association can help you learn more about Alzheimer's and other dementias, and help you find local support services. Call our 24/7 Helpline at 800.272.3900. Social Security Administration (SSA) has a "compassionate allowance" program in which workers diagnosed with Pick's disease, PPA or ALS can qualify for Social Security disability benefits. You can also call the SSA at 800.722.1213

Treatment and outcomes

Current frontotemporal dementia treatment focuses on managing symptoms, primarily those affecting behavior. Emerging insights into specific protein abnormalities associated with FTD may identify targets for new treatments aimed at underlying disease processes.

Antidepressants and antipsychotic drugs are the chief medications used to treat behavioral FTD symptoms. None of these drugs have been approved by the U.S. Food and Drug Administration (FDA) for use in FTD.

FTD inevitably gets worse, usually over several years. In advanced FTD, people typically become mute and bedbound. Like other types of dementia, FTD shortens lifespan. Studies suggest that most people with FTD survive an average of six to eight years, but survival can range from two to 20 years.

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