Frontotemporal dementia refers to a group of disorders that cause dementia to start at a younger age.
Around 60 percent of people who develop frontotemporal dementia are between the ages of 45 and 64 years. This type of dementia is uncommon.
Dementia is the decline in mental ability that is faster than would be expected with normal aging. Dementia affects everyday activities and gets progressively worse.
Symptoms of dementia include memory loss and difficulties with thinking, language, and problem-solving.
Frontotemporal dementia mainly affects the frontal and temporal lobes of the brain. The frontal lobe is located at the front of the brain, and the temporal lobe is located at the side of the brain. These areas of the brain are responsible for controlling behavior, personality, language, and the ability to plan and organize.
Less than 5 percent of all people who develop dementia have frontotemporal dementia.
The disorders that make up frontotemporal dementia fall into the following categories of symptoms, including:
- behavior and personality decline
- language decline
- motor decline
These symptoms are caused by damage to parts of the frontal and temporal lobes. The symptoms and the lobes that are affected determine the type of frontotemporal dementia a person has.
Behavior and personality decline
Behavior and personality decline is marked by progressive changes in a person's behavior, personality, emotions, and judgment.
These symptoms often mean that a person has a type of frontotemporal dementia called behavioral variant frontotemporal dementia.
Behavioral variant frontotemporal dementia may cause changes in personality, emotional blunting, and loss of empathy. Around 60 percent of people with frontotemporal dementia have behavioral variant frontotemporal dementia.
Language decline is marked by early changes in a person's language ability, which includes speaking, understanding, reading, and writing.
If a person displays language decline, they may have one of the types of frontotemporal dementia that include:
- progressive non-fluent aphasia - trouble producing speech
- semantic dementia - loss of the ability to understand single words, familiar people, and everyday objects
Around 20 percent of people with frontotemporal dementia have the progressive non-fluent aphasia subtype, and 20 percent have semantic dementia.
Motor decline refers to problems with physical movement. The person may have difficulties using limbs and walking. They may shake, frequently fall, and have poor coordination.
In some cases, motor disorders may occur with frontotemporal dementia. These include:
- motor neuron disease or ALS - a progressive disease that attacks the nerves in the brain and spinal cord
- progressive supranuclear palsy - a brain disorder that causes difficulties with walking, eye movements, and balance
- corticobasal syndrome - the gradual degeneration of movement, speech, memory, and swallowing
The cause of frontotemporal dementia is not entirely understood. However, the symptoms may occur because the frontal and temporal lobes of the brain shrink over time.
Shrinkage may happen due to a buildup of abnormal proteins in the brain that clump together. The cluster of abnormal proteins become toxic to brain cells and gradually kill them, which causes the brain areas to shrink.
While several gene mutations have been linked to types of frontotemporal dementia, most people with the condition do not have a family history of dementia.
Frontotemporal dementia and ALS have been shown to share genetics and molecular pathways. However, further studies are needed to work out the significance of this link.
Frontotemporal dementia symptoms vary from person to person and depend on the subtype of the disorder diagnosed.
Symptoms tend to cluster into categories of behavior and personality changes, language difficulties, and movement problems.
Eventually, most people with the condition will experience problems in more than one of these symptom categories, and the disease will spread to affect most of the brain's functions.
Behavior and personality changes
People who have the behavioral subtype of frontotemporal dementia may experience:
- problems with planning, judgment, sequencing, prioritizing, multitasking, and controlling behavior
- repetitive and obsessive behaviors, such as humming or walking the same route repeatedly
- impulsive and inappropriate behavior
- compulsive eating
- personal hygiene neglect
- irritability and aggression
- difficulty resisting the impulse to pick up and use objects for no apparent reason
- a lack of interest, enthusiasm, or initiative
- flat, improper, or exaggerated emotions
- an inability to read social signs, such as facial expressions
- loss of empathy, no emotional reaction
- being more or less outgoing
Quite often, the person with frontotemporal dementia is unaware that they have developed these unusual behaviors. As the disorder progresses, the person may become socially withdrawn and isolated.
The language subtypes of frontotemporal dementia cause symptoms such as:
- inability to understand and use words, but with normal physical speaking ability
- inability to physically speak properly or slurred speech, but with no effect on intelligence or understanding
- incorrectly using words
- reduced vocabulary
- repetition of a few phrases
- declining conversation and speech
Sometimes, people with frontotemporal dementia completely lose their ability to speak.
Movement problems that are associated with frontotemporal dementia include:
- inability to perform complex coordinated movements, such as eating with a knife and fork
- difficulty maneuvering small objects such as buttons and frequently dropping them
- uncontrollable contracting of muscles that cause abnormal postures
- walking abnormalities that cause shuffling or frequent falls
- muscle weakness and cramps
- shakiness that usually happens in the hands
- difficulty swallowing
Some people with frontotemporal dementia develop urinary incontinence and bowel incontinence.
Diagnosing frontotemporal dementia can be challenging, because other conditions can cause many of the same symptoms.
Doctors conduct several tests and assessments to make a correct diagnosis and rule out other potential conditions. A doctor may:
- assess symptoms
- evaluate mental abilities
- perform a physical examination
- review personal and family medical history
- order blood tests
- conduct brain scans to detect any loss of brain cells in the frontal and temporal brain regions
- order testing to identify genetic mutations
Research is ongoing to find a more accurate way to diagnose frontotemporal disorders at an earlier stage.
There is currently no way to slow down the progression of frontotemporal dementia and no cure. However, treatment can help manage some of the symptoms.
Treating behavioral problems
There is no medication specifically for frontotemporal dementia. The following medications may help with controlling behavioral problems and managing loss of inhibitions, overeating, and compulsive behavior in some people:
- antidepressants - trazodone or selective reuptake inhibitors (SSRIs), such as sertraline or fluvoxamine
- antipsychotics, such as olanzapine or quetiapine
People with frontotemporal dementia will be carefully monitored while taking these medications. The side effects of these drugs include a greater risk of death in people with dementia.
Coping with language difficulties
The goals of dealing with language difficulties in frontotemporal dementia include:
- maintaining language skills
- using tools and new ways to communicate
The person with frontotemporal dementia may need to communicate through a notebook, gestures, sign language, or drawings. They might also benefit from photos of people and objects being labeled with names.
Caregivers may need to speak slowly and clearly to the person using simple sentences and wait for a response. Strategies may need to be altered over time as the disease progresses.
Managing movement problems
There are no treatments to slow down the progression of movement problems that are related to frontotemporal dementia. However, certain medications and physical therapy may help with some symptoms.
Researchers continue to investigate more effective treatments for frontotemporal dementia.
One route researchers are currently studying is therapies that target the abnormal proteins that cluster in the brain that may be responsible for frontotemporal dementia.
Frontotemporal dementia is progressive. Most people with the disease will experience a decline in functions they use in everyday life. They may come to require around-the-clock care in a residential care facility.
If people have motor neuron disease-related or ALS-related frontotemporal dementia, they may live for around 3-5 years. However, people with other subtypes of the disease may live for 10 years or more. Survival time after symptoms begin can vary significantly.
Caring for someone with frontotemporal dementia can be stressful and challenging. Caregivers may need support from other family members, friends, and support groups.