What is Frontotemporal Dementia?
Alzheimer’s disease (AD) may be the most common and well-known form of dementia. But other disorders also affect brain function.
Frontotemporal dementia (FTD)–the fourth most common cause of dementia–is a group of disorders that occur when the nerve cells in the frontal and temporal lobes of the brain are damaged, causing the lobes to shrink. FTD can affect a person’s behavior, personality, language, and movement.
Facts about FTD
About 250,000 Americans have FTD. These diseases are among the most common dementias that strike at younger ages. Symptoms typically start between the ages of 40 and 65, but FTD can strike young adults and those who are older. FTD affects men and women equally.
The cause of FTD is unknown. Researchers have linked certain subtypes of FTD to mutations on several genes. Some people with FTD have tiny structures–called Pick bodies–in their brain cells. Pick bodies contain an abnormal amount or type of protein.
A family history of FTD is the only known risk for these diseases. Although experts believe that some cases of FTD are inherited, the majority of people with FTD have no family history of it or other types of dementia.
Types of FTD
The most common types of FTD are:
- Frontal variant. This form of FTD affects a person’s behavior and personality.
- Primary progressive aphasia. This form has two subtypes:
- Progressive nonfluent aphasia, which affects a person’s ability to speak.
- Semantic dementia, which affects a person’s ability to use and understand language.
A less common form of FTD affects a person’s movement, causing symptoms similar to Parkinson’s disease or amyotrophic lateral sclerosis, also known as Lou Gehrig’s disease.