The Different Types of Dementia: A Deep Dive

Dementia is a condition that is common among older adults. This condition involves the loss of cognitive function. That means it is difficult for people with dementia to think, remember, and reason.¹

Although dementia is not a normal part of aging, it is very common among older adults. About one-third of people over the age of 85 likely have some type of dementia. There are many types of dementia, including:¹

1. Alzheimer's
2. Lewy body dementia
3. Frontotemporal dementia
4. Vascular dementia
5. Other rare forms of dementia

Alzheimer's disease

Alzheimer’s disease is the most common form of dementia. With Alzheimer's, a person's skills slowly worsen over time. The person with Alzheimer's may have more trouble with their memory, thinking, and carrying out simple tasks. They may have difficulty:^1,2

• Driving a car
• Cooking a meal
• Paying bills
• Remembering people and events
• Keeping track of their belongings

Alzheimer's typically affects people who are in their mid-60s. It can occur as early as age 30, but this is very rare.²

Lewy body dementia

Lewy body dementia (LBD) is another common form of dementia. LBD affects more than 1 million people in the United States. This condition occurs when there are abnormal deposits of Lewy bodies. Lewy bodies are proteins in the brain. Having abnormal deposits of these proteins can lead to problems with:³

• Thinking
• Movement
• Behavior
• Mood

There are 2 subtypes of Lewy body dementia: dementia with Lewy bodies (DLB) and Parkinson's disease dementia. These types of LBD are similar in how they show up. But they are different in when the thinking (cognitive) and movement symptoms start.³

For instance, people with DLB typically develop cognitive symptoms within a year of when the movement symptoms start. For people with Parkinson's disease dementia, cognitive symptoms occur more than a year after movement symptoms start.³

Frontotemporal dementia

Frontotemporal dementia (FTD) is also called frontotemporal disorders. This is a group of disorders that occur when there is damage to the cells in the brain. Symptoms include:⁴

• Unusual behavior
• Emotional problems
• Trouble communicating
• Difficulty with work
• Difficulty walking

There are quite a few types of FTD.⁴

Behavioral variant frontotemporal dementia

People who have behavioral variant frontotemporal dementia (bvFTD) often have problems with thinking. But usually their memory still operates as it normally would.⁴

BvFTD is a progressive disorder, like most types of dementia. This means that the symptoms will get worse over time and a person with this disease may need more care and supervision as the disease progresses. Symptoms of bvFTD may include:⁴

1. Difficulty planning
2. Difficulty thinking through which steps come first, second, etc.
3. Repeating the same activity
4. Repeating words over and over
5. Acting impulsively or doing inappropriate things

Primary progressive aphasia

Primary progressive aphasia (PPA) is a disorder that makes it difficult for the person who has it to communicate. It is hard for people with PPA to use language to speak, read, and write. They also have trouble understanding what other people are saying. These are the different types of PPA:⁴

1. Semantic PPA – The person slowly loses the ability to understand words and recognize the faces of the people in their life
2. Agrammatic PPA – The person has difficulty speaking and eventually may not be able to speak at all
3. Logopenic PPA – The person has difficulty finding the right words in conversation but can understand when other people are speaking

Movement disorders

There are 3 types of FTD that are movement disorders, meaning that the part of the brain that controls movement is affected. These types are:⁴

1. Corticobasal syndrome – Over time, a person with this condition will lose the ability to control their movement
2. Progressive supranuclear palsy – Symptoms are similar to Parkinson's disease (body stiffness, unexplained falls, slow movement, etc.) and often relate to problems with balance and walking

Frontotemporal dementia with parkinsonism – Also has symptoms that are similar to Parkinson's disease as well as changes in behavior or language

3. FTD-ALS – This is a combination of FTD and ALS (amyotrophic lateral sclerosis, also known as Lou Gehrig's disease) that can cause behavior and language symptoms as well as muscle weakness

Vascular dementia

Vascular dementia occurs when there are conditions that affect the blood vessels in the brain. These conditions may interrupt the flow of blood and oxygen to the brain and cause damage to the blood vessels.⁵

Symptoms of vascular dementia can occur gradually or suddenly. They may also get worse over time or have periods of improvement. Vascular dementia can be a part of other types of dementia like Alzheimer's disease.⁵

Some people who have vascular dementia may have had a previous stroke that led to damaged blood vessels. They may also have had abnormal changes in the white matter of their brain.⁵

Subcortical vascular dementia (Binswanger's)

Subcortical vascular dementia, also called Binswanger's disease, is a type of vascular dementia. Binswanger's disease is when there is damage to the blood vessels of the white matter in the brain.⁶

The nerves in the brain have a protective coating called myelin. The nerve fibers surrounded by myelin are called white matter. When there is damage to the white matter, the arteries in the brain become thick and narrow. This causes a decrease in the blood supply to the brain.⁶

Symptoms of Binswanger's disease include:⁶

• Unsteady walking
• Changes in behavior, attention, and mood
• Difficulty speaking and swallowing
• Progressive loss of thinking, ability to make decisions and organize things, and memory

Other forms of dementia

There are many different forms of dementia. And there are many conditions that lead to dementia, too. Here are a few examples:^7,8

• Huntington's disease, which causes a gradual breakdown of the nerve cells in the brain. This breakdown leads to movement symptoms and cognitive changes including dementia.
• Creutzfeldt-Jakob disease, which is a rare, progressive condition. It causes changes in muscle coordination, thinking, and memory.

A person can also have mixed dementia. This means that they have 2 or more types of dementia.¹