Frontal temporal dementia is a degenerative condition of the temporal and frontal lobes of the brain. This irreversible form of dementia accounts for about 2-5 percent of all dementia cases.

While 60 percent of people develop frontotemporal dementia (FTD) with no known cause, the other 40% have a family history of the condition, according to the University of California San Francisco.

Frontotemporal dementia was once known as Pick's disease, named for the abnormal protein-filled structures (Pick bodies) that develop in the brain cells of some patients.

Types of FTD

There are three variants of FTD:

  • Behavioral variant FTD (bvFTD): The most common form seen in about 60 percent of FTD patients is behavioral variant FTD. Brain degeneration affects areas controlling social skills, emotions, personal conduct and self-awareness. Unlike most forms of dementia, patients don't show signs of forgetfulness at first. Rather, behavioral changes are most noticeable before the condition spreads.
  • Semantic dementia: Seen in 20 percent of FTD cases, this variant damages areas of the brain that assign meaning to words. Patients may start replacing less common words with “thing" and eventually call even well known words “thing." The loss of empathy is an early symptom in this form of FTD.
  • Progressive nonfluent aphasia (PNFA): The other 20 percent of patients affected by this variant still know the meaning of words, but have difficulty speaking them. They may speak very slowly and struggle to pronounce words. Eventually, patients develop severe Parkinson's disease symptoms, such as: the inability to move eyes side-to-side, muscle rigidity in arms and legs, weakened throat muscles (making swallowing difficult) and being more prone to falls.

Additional Symptoms

In general, FTD patients show impairments in social skills; they may be inappropriate in public and seem to have no inhibitions about what they say or do. FTD affects judgment, so patients are more likely to engage in impulsive behaviors and not recognize the consequences, according to Northwestern University.

They may either stop caring about their personal appearance altogether, or become compulsive about their personal hygiene regimen. Changes in personality can make FTD patients more irritable and easily frustrated. They can be both unsympathetic and overly emotional, since the affected area of the brain controls behavior, insight and reasoning.

About 15 percent of patients develop motor neuron disease (MND) along with FTD, characterized by slurred speech, difficulty swallowing, choking, muscle wasting and arm and leg weakness.

How Common Is FTD?

FTD is the most common cause of dementia in people under 60. Typically the condition first appears in their mid-40s to early 60s. On average, the disease lasts eight years from diagnosis to death.

Due to similarities with other conditions, FTD is often misdiagnosed as Alzheimer's disease, vascular dementia, Parkinson's disease or another psychiatric problem. An MRI will determine whether or not a patient has FTD, since specific areas of the brain are damaged.

Although there is no cure for FTD, lifestyle changes and medications can ease symptoms. Mayo Clinic suggests speech therapy for patients dealing with language difficulties.