Frontotemporal dementia

Frontotemporal dementia (FTD), also known as frontotemporal degeneration, and historically as Pick's disease, is a family of neurodegenerative disorders, caused by frontotemporal lobar degeneration that affects the frontal and temporal lobes. The FTD family includes behavioral variant FTD, primary progressive aphasia (PPA) and its semantic and nonfluent/agrammatic variants. primary progressive apraxia of speech (PPAOS), progressive supranuclear palsy, and corticobasal syndrome.

Through a mutual risk gene, FTD and amyotrophic lateral sclerosis (ALS) share a clinical spectrum, where symptoms of both disorders can co-occur. Symptoms of FTD will typically match a specific disorder at first, though symptoms of other disorders will begin to show as the disease progresses to different areas of the brain. FTD disorders are a common young-onset dementia occurring under the age of 60.

Approximately 60% of people diagnosed with FTD have no known cause and no family history of FTD or related conditions; this is known as sporadic FTD. While environmental causes and unidentified gene variants are suspected causes of sporadic FTD, research in this area is still ongoing. When people have a family history of FTD, other dementias, or conditions like depression and anxiety, it is referred to as familial FTD, and roughly 20% have an underlying genetic basis. Variants in three genes are responsible for most genetic FTD. Notably, in about 10% of people with seemingly sporadic FTD, a genetic variant is identified.

FTD diagnosis currently relies on clinical examination based on the signs and symptoms experienced and imaging of the brain through magnetic resonance imaging or positron emission tomography. FTD disorders have heterogeneous symptoms and pathological features, which contribute to a lengthy differential diagnostic process and high rates of misdiagnosis. A neuropathologicalexamination after death usually provides a definitive diagnosis by identifying the specific features of FTD subtypes.

There is no cure for FTD, nor are any disease-modifying treatments approved that could slow disease progression. The aim of treatment is to manage symptoms, which is primarily accomplished through non-pharmacological interventions such as person-centric care strategies or physical and occupational therapy. Medication can be used to address symptoms like depression or anxiety, but some drugs, like sleep or antipsychotic medicines, carry a considerable risk of side effects for people with FTD. Death is usually the result of complications of FTD, such as pneumonia or fall-related injuries. The average life expectancy after symptoms start is 7 to 13 years, but varies significantly by individual and FTD subtype.

The clinical features of FTD were first described by Czech-GermanpsychiatristArnold Pick between 1892 and 1906. Pick's observations were followed by Alois Alzheimer's first description of tau aggregations in neurons (called "Pick bodies") in 1911. The disorder described by Pick was named "Pick's disease" in 1922. The first research criteria were created in 1994, and the publication was the first to use the term "frontotemporal dementia".