It's possible for someone to have more than one type of dementia. When this happens, it's known as mixed dementia.
What is mixed dementia?
Because different types of dementia can have different causes, it's possible for a person to have more than one type of dementia. When this happens, that person has mixed dementia.
A person living with mixed dementia will show symptoms of at least two different types of dementia. Usually, mixed dementia consists of the two most common types: Alzheimer’s disease and vascular dementia.
For example, a person with mixed dementia may show symptoms of both Alzheimer's and vascular dementia. Because many symptoms overlap between different types of dementia, it can be hard to figure out if someone has mixed dementia.
However, it's important that we are aware whether someone has mixed dementia, because the combination of two or more dementias will likely have a greater impact on their brain than experiencing one disease alone. This can affect how a person progresses through the stages of dementia.
How many people have mixed dementia?
Researchers don’t know exactly how many people currently diagnosed with a specific type of dementia actually have mixed dementia. However, autopsy studies indicate that mixed dementia may be much more common than previously realized.
Why do we perform autopsy studies? Autopsy studies play a key role in shedding light on mixed dementia because scientists can't yet measure most dementia-related brain changes in living individuals.
Some experts recommend suspecting mixed dementia whenever a person has both evidence of cardiovascular disease and dementia symptoms that get worse slowly over time. Evidence like this may indicate the presence of both Alzheimer's disease and vascular dementia.
How can I find out if I have mixed dementia?
Because of its nature, mixed dementia is difficult to diagnose. List the symptoms that you notice and discuss them with your doctor or a qualified healthcare provider.
How can mixed dementia be treated?
Like any other dementia, the best way to treat the effects of mixed dementia is to follow a brain-healthy lifestyle. This also holds true for reducing the risk of mixed dementia.
Depending on the symptoms experienced, someone living with mixed dementia may find relief with medications approved to treat Alzheimer's disease as well as certain alternative treatments. Before starting any treatment, however, the Alzheimer Society strongly recommends checking with a doctor or a qualified healthcare provider first.
More useful links and resources
Mixed dementia. Alzheimer's Association. This U.S.-focused webpage covers symptoms, diagnosis, risk factors and treatment for mixed dementia.
Rare Dementia Support Canada. Provides a free specialist Information and support service for people living with, or affected by, a diagnosis of rare or young onset dementia.