Last year, actor Bruce Willis retired from acting after being diagnosed with aphasia. A from his family revealed that Willis' condition has progressed and he's now been diagnosed with frontotemporal dementia (FTD).
"FTD is a cruel disease that many of us have never heard of and can strike anyone," the statement noted. "For people under 60, FTD is the most common form of dementia, and because getting the diagnosis can take years, FTD is likely much more prevalent than we know. Today there are no treatments for the disease, a reality that we hope can change in the years ahead. As Bruce's condition advances, we hope that any media attention can be focused on shining a light on this disease that needs far more awareness and research."
FTD is a characterized by neuronal degeneration in the frontal and anterior temporal lobes of the brain. It occurs in 2.2 per 100,000 people ages 40-49, in 3.3 per 100,000 in those ages 50-59, and 8.9 per 100,000 in those ages 60-69. FTD tends to occur at a younger age compared with other forms of dementia. Roughly 60% of people with FTD are 45 to 64 years old.
FTD is a progressive disease, and may start with a single symptom. As time goes on, more areas of the brain are affected, and new symptoms emerge. It is difficult to predict how many years a person will live after diagnosis. It can be less than 2 years or even more than 10 years. The average survival time is 7.5 years.
FTD targets areas of the brain that are responsible for personality, behavior, language learning, motivation, abstract thinking, and executive function. Language problems and behavioral changes are often the first symptoms, with loss of cognitive and executive functions coming later.
There are two main clinical types of FTD -- behavioral variant and language type. Behavior-variant FTD -- the most frequent phenotype of FTD -- is characterized by prominent changes in personality and behavior. Nerve cell loss is most prominent in areas of the brain that control conduct, judgement, empathy, and foresight.
Language-type FTD is often referred to as primary progressive aphasia (PPA), which has two types: nonfluent-variant PPA and semantic-variant PPA. Those with the semantic variant lose the ability to understand or formulate words in a spoken sentence, while the nonfluent variant causes a person's speaking to be very hesitant, labored, or ungrammatical.
Behavior-variant FTD and semantic-variant PPA are more prevalent in men, while nonfluent-variant PPA predominantly occurs in women.
Although FTD is mostly a sporadic disease, genetics can play a key role in some families. Forty percent of cases have a familial origin, and 14% are inherited in an autosomal dominant fashion. Mutations in more than 20 genes have been identified as potential links to the development of FTD, including , and .
Symptoms
Behavior-variant FTD
People with behavior-variant FTD may have problems with cognition, but their memory may stay relatively intact. Symptoms can include:
- Problems planning and sequencing (thinking through which steps come first, second, and so on)
- Difficulty prioritizing tasks or activities
- Repeating the same activity or saying the same word over and over
- Acting impulsively or saying or doing inappropriate things without considering how others perceive the behavior
- Becoming disinterested in family or activities
These symptoms are frequently misunderstood. Family and friends may think a person is consciously misbehaving, which can lead to anger and conflict. Contacts should be educated that the behaviors can't be controlled by the patient who may also lack any awareness of their illness.
Over time, language and/or movement problems may occur, and patients will need more care and supervision.
PPA
PPA involves changes in all aspects of communication -- the ability to use language to speak, read, write, and understand what others are saying. People with PPA can have difficulty using or understanding words, as well as difficulty speaking properly. They may become mute.
Many people with PPA develop symptoms of dementia. Problems with memory, reasoning, and judgment are not apparent at first, but can develop over time. In addition, some people with PPA may experience significant behavioral changes, like those seen with behavior-variant FTD, as the disease progresses.
People with semantic-variant PPA slowly lose the ability to understand single words, and in some cases, to recognize the faces of familiar people and common objects.
A person with nonfluent-variant PPA has more and more trouble speaking and may omit words such as "to," "from," and "the." Eventually, the person may no longer be able to speak at all.
Treatment
Currently, there is no cure for FTD and no way to slow the progression of the disease. Caring for patients with FTD takes a multidisciplinary approach, including social support services, physical therapy, occupational therapy, speech therapy, cognitive behavioral therapy, rehabilitation services, and caregivers' education. Patients and caregivers should also be periodically assessed for their ability to maintain activities of daily living.
Michele R. Berman, MD, is a pediatrician-turned-medical journalist. She trained at Johns Hopkins, Washington University in St. Louis, and St. Louis Children's Hospital. Her mission is both journalistic and educational: to report on common diseases affecting uncommon people and summarize the evidence-based medicine behind the headlines.