Frontotemporal dementia, which refers to a group of dementias, results from hereditary or spontaneous (occurring for unknown reasons) disorders that cause the frontal and sometimes the temporal lobe of the brain to degenerate.
- Personality, behavior, and language function are affected more and memory less than in Alzheimer disease.
- Doctors base the diagnosis on symptoms and results of a neurologic examination and use imaging tests to assess the brain damage.
- Treatment aims to manage symptoms.
Dementia is a slow, progressive decline in mental function including memory, thinking, judgment, and the ability to learn.
Dementia differs from delirium, which is characterized by an inability to pay attention, disorientation, an inability to think clearly, and fluctuations in the level of alertness.
- Dementia affects mainly memory, and delirium affects mainly attention.
- Dementia typically begins gradually and has no definite beginning point. Delirium begins suddenly and often has a definite beginning point.
About 1 of 10 dementias is a frontotemporal dementia. Typically, the dementia develops in people younger than 65. Men and women are affected about equally.
Frontotemporal dementias tend to run in families. About half of frontotemporal dementias are inherited.
Brain cells contain abnormal amounts or types of a protein called tau.
In these dementias, the frontal and temporal lobes shrink (atrophy), and nerve cells are lost. These areas of the brain are generally associated with personality and behavior.
There are several types of frontotemporal dementia. For example, Pick disease is a term used to describe some of the changes in the brain caused by a specific type of frontotemporal dementia. It is characterized by severe atrophy, loss of brain cells, and the presence of abnormal brain cells (Pick cells).
Frontotemporal dementias are progressive, but how quickly they progress to general dementia varies.
Generally, these dementias affect personality, behavior, and language function more and affect memory less than Alzheimer disease does. People with a frontotemporal dementia also have difficulty thinking abstractly, paying attention, and recalling what they have been told. They have difficulty putting ideas or doing actions for a task in the right order (sequencing). They are easily distracted. However, they usually remain aware of time, date, and place and are able to do their daily tasks.
In some people, muscles are affected. They may become weak and waste away (atrophy). Muscles of the head and neck are affected, making swallowing, chewing, and talking difficult. They may inhale (aspirate) food, sometimes resulting in aspiration pneumonia.
Different types of symptoms develop, depending on which part of the frontal or the temporal lobe is affected. They include
- Changes in personality and behavior
- Problems with language
People may have more than one type of symptom, particularly as the dementia progresses.
Changes in personality and behavior
Some people with frontotemporal dementia become uninhibited, resulting in increasingly inappropriate behavior. They may speak rudely. Their interest in sex may increase abnormally.
Behavior may become impulsive and compulsive. They may repeat the same action over and over. They may walk to the same location every day. They may compulsively pick up and manipulate random objects and put objects in their mouth. They may suck or smack their lips. They may overeat or eat only one type of food.
People with this type of frontotemporal dementia neglect personal hygiene.
Problems with language
Most people with frontotemporal dementia have difficulty finding words. They have increasing difficulty using and understanding language (aphasia). For some, physically producing speech (dysarthria) is difficult. Paying attention is very difficult. For some people, language problems are the only symptom for 10 or more years. For other people, other symptoms appear within a few years.
Some people cannot understand language, but they speak fluently, although what they say does not make any sense. Others have difficulty naming objects (anomia) and recognizing faces (prosopagnosia).
As dementia progresses, people speak less and less or repeat what they or others say. Eventually, they stop speaking.
- A doctor's evaluation
- Computed tomography or magnetic resonance imaging
Doctors must determine whether a person has dementia and, if so, whether the dementia is frontotemporal dementia.
Diagnosis of dementia
A diagnosis of dementia is based on the following:
- Symptoms, which are identified by asking the person and family members or other caregivers questions
- Results of a physical examination, including a neurologic examination
- Results of a mental status test
- Results of additional tests, such as computed tomography (CT) or magnetic resonance imaging (MRI)
Family members may have to provide information about symptoms because affected people may be unaware of their symptoms.
Mental status testing, consisting of simple questions and tasks, helps doctors determine whether people have dementia.
Sometimes more detailed testing (called neuropsychologic testing) is needed. This testing covers all the main areas of mental function, including mood, and usually takes 1 to 3 hours. This testing helps doctors distinguish dementia from other conditions that can cause similar symptoms, such as age-associated memory impairment, mild cognitive impairment, and depression.
Information from the above sources helps doctors usually rule out delirium as the cause of symptoms (see table Comparing Delirium and Dementia). Doing so is essential because delirium, unlike dementia, can often be reversed if promptly treated.
Diagnosis of frontotemporal dementia
The diagnosis of frontotemporal dementia is based on its typical symptoms, including how they developed.
Computed tomography (CT) and magnetic resonance imaging (MRI) are done to determine which parts and how much of the brain is affected and to exclude other possible causes (such as brain tumors, abscesses, or a stroke). However, CT or MRI may not detect the characteristic changes of frontotemporal dementia until late in the disorder.
Positron emission tomography (PET), another type of imaging test, may help differentiate frontotemporal dementia from Alzheimer disease.
- Relief of symptoms
- Supportive measures
There is no specific treatment for frontotemporal dementia.
Generally, treatment focuses on
- Managing symptoms
- Providing support
For example, if compulsive behavior is a problem, antipsychotic drugs may be used. Speech therapy may help people with language problems.
Safety and supportive measures
Creating a safe and supportive environment can be very helpful.
Generally, the environment should be bright, cheerful, safe, stable, and designed to help with orientation. Some stimulation, such as a radio or television, is helpful, but excessive stimulation should be avoided.
Structure and routine help people with frontotemporal dementia stay oriented and give them a sense of security and stability. Any change in surroundings, routines, or caregivers should be explained to people clearly and simply.
Following a daily routine for tasks such as bathing, eating, and sleeping helps people with frontotemporal dementia remember. Following a regular routine at bedtime may help them sleep better.
Activities scheduled on a regular basis can help people feel independent and needed by focusing their attention on pleasurable or useful tasks. Such activities should include physical and mental activities. Activities should be broken down in small parts or simplified as the dementia worsens.
Care for caregivers
Caring for people with dementia is stressful and demanding, and caregivers may become depressed and exhausted, often neglecting their own mental and physical health. The following measures can help caregivers (see table Caring for Caregivers):
- Learning about how to effectively meet the needs of people with dementia and what to expect from them: Caregivers can get this information from nurses, social workers, organizations, and published and online materials.
- Seeking help when it is needed: Caregivers can talk to social workers (including those in the local community hospital) about appropriate sources of help, such as day-care programs, visits by home nurses, part-time or full-time housekeeping assistance, and live-in assistance. Counseling and support groups can also help.
- Caring for self: Caregivers need to remember to take care of themselves. They should not given up their friends, hobbies, and activities.
Before people with frontotemporal dementia become too incapacitated, decisions should be made about medical care, and financial and legal arrangements should be made. These arrangements are called advance directives. People should appoint a person who is legally authorized to make treatment decisions on their behalf (a health care proxy). They should discuss their health care wishes with this person and their doctor. Such issues are best discussed with all concerned long before decisions are necessary.
As frontotemporal dementia worsens, treatment tends to be directed at maintaining the person’s comfort rather than at attempting to prolong life.