Mixed dementia means that a person has Alzheimer’s and cerebrovascular dementia. Sometimes people may also use the term more broadly to refer to any condition in which a person has two or more types of dementia.

Cerebrovascular dementia is dementia that results from the accumulated effects of strokes. This occurs when a person has cardiovascular disease such as atherosclerosis.

Alzheimer’s disease is the most common form of dementia, but there are more than a dozen broad categories of dementia and even more subtypes.

Identifying the type of dementia a person has may help doctors determine the outlook. Medications and interventions may have varying effects on different types of dementia, so an accurate diagnosis may guide treatment decisions. However, there is no cure for dementia, and treatment offers only limited improvement in a small number of people.

Read on to learn more about mixed dementia.

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Dementia is a category of conditions that affect cognitive functioning. Dementia has many forms, including:

Mixed dementia occurs when a person has more than one type of dementia at the same time. In most cases, doctors and researchers use the term “mixed dementia” to refer to the combination of Alzheimer’s disease and vascular dementia.

Learn more about the different types of dementia.

It is not possible to determine which type of dementia a person has based on symptoms alone. Dementia affects many aspects of brain function and tends to be progressive, affecting more aspects of memory, cognition, and self-care abilities over time. Different types of dementia may look more similar as they get worse.

Symptoms to look for include:

  • changes in personality or mood
  • memory problems, including short-term memory difficulties in the early days of symptoms
  • behavior changes
  • difficulty with daily tasks such as driving and navigating the world
  • trouble with self-care
  • changes in speech, such as severe difficulty finding the right words

A doctor may suspect mixed dementia if imaging scans show changes in the brain that are consistent with multiple forms of dementia.

The symptoms of some other diseases can mimic those of dementia, so a person should not assume that any memory loss or change in the ability to think is a result of dementia.

Learn more about the early signs of dementia.

Mixed dementia is a multifactorial disease, which means that many causes and risk factors contribute to its development. Researchers have not identified a specific cause.

The main risk factors include:

  • advancing age
  • cerebrovascular disease such as atherosclerosis
  • history of stroke
  • Down syndrome, which is a risk factor for early Alzheimer’s disease
  • family history of dementia
  • traumatic head injury
  • history of cardiovascular risk factors such as smoking and high blood pressure

Learn more about what might cause a sudden worsening of dementia symptoms.

There is no gold standard for diagnosing mixed dementia. In general, a person must have symptoms of Alzheimer’s disease and symptoms of cardiovascular disease.

A combination of tests, such as the following, can help a doctor determine which type of dementia a person has:

  • cognitive function testing
  • brain imaging scans
  • tests that detect and monitor for cardiovascular disease
  • other medical tests

In some cases, a doctor may do testing to rule out other causes, such an infection or a head injury.

Learn more about cognitive tests that can aid in diagnosis.

There is no cure for any form of dementia, including mixed dementia.

Treatments — especially drugs for Alzheimer’s disease — may help slow the progression of the disease. They may also offer modest but temporary improvements in cognitive functioning. Several drugs are available, and the right drug for each person depends on factors such as:

  • the person’s health status
  • the severity of symptoms
  • the person’s treatment preferences

Additionally, a person may need to take medications to manage vascular disease, such as blood pressure drugs or cholesterol-lowering drugs. These drugs can slow the progression of vascular disease and help lower the risk of stroke and heart attack.

Other medications to manage symptoms and supportive care can also help. For example, a person with severe memory loss may need to live in a supportive environment or need daily support with self-care tasks.

Learn more about aducanumab, a new drug for dementia.

Dementia is a progressive disease that steadily erodes brain function. This can eventually affect all aspects of functioning, including bladder and bowel control, basic self-care, and life-sustaining functions such as breathing.

Mixed dementia is also progressive, becoming worse over time. However, medications that help manage vascular disease can slow the progression and prevent additional complications.

Learn more about the outlook for Alzheimer’s disease.

What is the life expectancy with mixed dementia?

Like other forms of dementia, mixed dementia is a terminal illness.

People with mixed dementia typically have other medical conditions as well, such as cardiovascular disease. Because they may die either from dementia or from these other conditions, they have a shorter overall life expectancy than people without these conditions.

A 2018 Norwegian study found that, on average, mixed dementia takes 10 years off a person’s life.

Below are some commonly asked questions on the topic:

What is the most common mixed dementia?

The term “mixed dementia” typically means that a person has vascular dementia and Alzheimer’s disease, so that is the most common type of mixed dementia.

However, some people apply this term to people who have multiple types of dementia or develop a second form of dementia after receiving a diagnosis of one type.

Is mixed dementia hereditary?

Researchers have not identified a single gene or combination of genes that causes dementia. However, having an immediate family member with Alzheimer’s disease is a significant risk factor.

Vascular dementia, the second component of mixed dementia, develops from cardiovascular disease. Lifestyle and genetics together play a role in the development of vascular disease.

Does mixed dementia progress quickly?

Survival is shorter in mixed dementia than in most other types of dementia. This is because a person has not only dementia but also underlying cardiovascular disease that may kill or injure them.

However, dementia is an unpredictable illness, and there is no way to predict how an individual’s condition will progress.

Mixed dementia occurs when more than one form of dementia causes a person’s symptoms. In most cases, doctors use this term to refer to a combination of cerebrovascular dementia and Alzheimer’s disease, though they may less commonly use it to refer to other combinations of dementia types.

People with mixed dementia need medical care to get the right diagnosis and to explore treatment options. A person who has memory loss, personality changes, or other changes in their abilities or cognition should consult a doctor.