What is the definition of Primary Progressive Aphasia?
Primary progressive aphasia (PPA) affects a person's ability to use language to communicate. This includes difficulty making or understanding speech (aphasia). PPA is a specific type of a more general disease called frontotemporal dementia. PPA can be classified into three distinct types which include:
PPA is caused by a loss of tissue (atrophy) in the area of the brain that is responsible for producing language. In some cases, this loss of tissue is caused by genetic changes (
- Progressive non-fluent aphasia (PNFA)
- Semantic dementia (SD)
- Logopenic progressive aphasia (LPA)
mutations or pathogenic variants) in the
GRN gene. In these cases, the disease is inherited in an
autosomal dominant manner. Diagnosis of PPA is suspected when a doctor observes signs and symptoms such as progressive loss of language abilities. Imaging of the brain with a
CT scan or
MRI can confirm the diagnosis. Although there is no cure for the disease, treatment options include
speech therapy and medication to manage behavioral changes.
What are the alternative names for Primary Progressive Aphasia?
- Aphasia, primary progressive
- Primary progressive aphasia syndrome
What are the causes for Primary Progressive Aphasia?
Primary progressive aphasia (PPA) is caused by a loss of tissue (atrophy) in the area of the brain that is responsible for language. This loss of brain tissue causes people with PPA to slowly lose their ability to find the right words they want to say or to understand words that other people say.
In some cases, PPA is caused by genetic changes (mutations or pathogenic variants) in the GRN gene. However, most cases of PPA are thought to be caused by a combination of genetic and environmental factors. People who have learning disabilities may be more likely to develop PPA.
What are the symptoms for Primary Progressive Aphasia?
Symptoms of primary progressive aphasia (PPA) usually begin gradually. The age that symptoms begin is typically between 50-70 years. The first symptoms of the disease may include speech problems and behavioral changes. Speech problems may include difficulty naming objects, difficulty forming words, frequent pauses in speech, slow speech, difficulty comprehending speech, and problems with grammar. In general, speech problems are the primary symptom of PPA for the first couple of years. Eventually some people may develop problems with judgement and other cognitive skills.
PPA is a progressive disease, meaning the symptoms generally worsen over time. People who have PPA may become unable to speak (mute) and completely lose the ability to understand written or spoken language. Some people develop symptoms of depression as the disease progresses. In some cases, progressive language loss may be the initial symptom of another neurodegenerative disease, such as Alzheimer disease.
What are the current treatments for Primary Progressive Aphasia?
Unfortunately, there is no cure for primary progressive aphasia (PPA). Treatment is focused on slowing the progression of the disease and helping the person to adapt to the loss of language skills in everyday life. For example, speech therapy may be a helpful tool for people with PPA to maintain language skills for as long as possible. Some people benefit from learning sign language or other ways to communicate.
Selective serotonin reuptake inhibitors (SSRIs) can be used to treat behavioral changes that may be associated with PPA. These medications may also help treat symptoms of anxiety or depression, which can impact people who have PPA. Clinical trials are ongoing to try to determine more effective treatments for PPA.
What is the outlook (prognosis) for Primary Progressive Aphasia?
Primary progressive aphasia (PPA) is typically a progressive disease, meaning that people who have the disease tend to continue to lose language skills. Many people who have the disease eventually completely lose the ability to use language to communicate.
People who have the disease typically live about 3-12 years after they are originally diagnosed. In some people, difficulty with language remains the primary symptom, while others may develop additional problems including cognitive or behavioral changes or difficulty coordinating movements. Many people with PPA eventually require care and monitoring at home to help them in daily life. People who have PPA may be more likely to experience complications such as an injury or infections such as pneumonia.
How is Primary Progressive Aphasia diagnosed?
Primary progressive aphasia (PPA) may be suspected when a person has signs and symptoms of the disease including behavioral changes and progressive loss of language abilities. A doctor may then take a thorough personal medical history and family history to look for other signs of the disease. Most people who have PPA begin to develop symptoms suddenly, and they experience a progressive loss of language skills for two years without other loss of cognitive function. Imaging of the brain using a CT scan or MRI may confirm the diagnosis. In some cases, the exact type of disease that a person has cannot be determined until after he or she has passed away.
Is Primary Progressive Aphasia an inherited disorder?
About 40-50% of people with primary progressive aphasia (PPA) have other family members who are also affected by the disease. When PPA is caused by a genetic change (
mutations or pathogenic variants) in the GRN gene, it is inherited in an autosomal dominant manner. Like most genes, the GRN gene comes in a pair. One copy of the gene comes from the mother and the other copy from the father. Autosomal dominant means that only one copy of the GRN gene needs to have a pathogenic variant for a person to develop PPA.
When a person who has a pathogenic variant in the GRN gene has children, each child has a:
Most cases of PPA are not caused by a pathogenic variants in the GRN gene, but PPA can still run in families. In these situations, the disease is likely more common in the family because of shared genetic and environmental factors.
- 50% chance to inherit the changed copy of the GRN gene, meaning he or she is at an increased risk to develop PPA
- 50% chance to inherit the working copy of the GRN gene, meaning he or she is not at an increased risk to develop PPA