Dementia is the umbrella term for a group of diseases which affect the brain
To get a diagnosis of dementia, a doctor will have found that the person you care for is having difficulty with things such as changes in their memory or thinking, which makes it harder for them to go about daily life.
The diseases which cause dementia can be thought of as affecting the parts of the brain that are needed to remember and learn. Medications and non-drug treatments, such as cognitive training, can help keep these parts of the brain to work the best way they can.
Common types of dementia:
Each type of dementia is different
Each type of dementia has different patterns of change in the brain, different patterns of symptoms, and different drug treatments. However, non-drug strategies and treatments for symptoms tend to work for all types of dementia. It is not always possible for the physician to make a definitive diagnosis of the exact cause of dementia, but treatments will still be offered based on the most likely cause.
Alzheimer’s disease
Alzheimer’s disease is the most common type of dementia. About 50-70% of all people with dementia have Alzheimer’s disease. People with Alzheimer’s disease typically have trouble with short-term memory. Often, remembering recent events (short term memory) is affected more than their ability to remember events from their past (long term memory). They may also find it harder to concentrate and solve complex problems or find themselves thinking more slowly. People with Alzheimer’s disease typically have deterioration in the areas of their brain involved in memory (I.e., the hippocampus and temporal lobes), as well as more general changes throughout the brain.
We don’t know what causes Alzheimer’s disease, however there are medications which can slow the progression of symptoms. A healthy lifestyle including exercise, diet, and staying mentally active can also help.
Read more about Alzheimer’s disease from the Alzheimer’s Society of Canada.
Vascular dementia
Vascular dementia is another common form of dementia. It is caused by poor blood flow in the brain, and this can lead to brain cells dying, mini-strokes, or larger strokes. The cognitive challenges that people with vascular dementia have may vary, depending on where their brain has been damaged.
People with vascular dementia usually have heart disease or risk factors for heart disease such as high cholesterol and high blood pressure. Managing these heart disease risk factors can help slow the progression of vascular dementia. Talk with the person with dementia and their doctor about treatments and strategies to manage heart disease risk.
Read more about Vascular Dementia at Alzheimer’s Society of Canada.
Fronto-temporal dementia
Fronto-temporal dementia is a less common type of dementia. People with fronto-temporal dementia have damage in the frontal and temporal lobes (regions) of their brains. People with fronto-temporal dementia don’t usually have symptoms typical of other dementias, so they sometimes find that clinicians don’t recognize that they have dementia or don’t understand how to support their type of dementia. People with fronto-temporal dementia and their care partners have told us they sometimes have to educate their health or social care providers about fronto-temporal dementia.
There are three subtypes of fronto-temporal dementia, each with a different pattern of symptoms.
- Semantic variant of primary progressive aphasia is a subtype of fronto-temporal dementia where the person starts to lose the meanings of words. People with semantic dementia have trouble expressing themselves with words, understanding language, reading and writing. They may particularly benefit from working with a speech language pathologist, as they can provide therapy to improve communication (see: 3.13 Use therapies to help people maintain independence). Brain changes start in the temporal lobe in semantic dementia.
- Progressive non-fluent aphasia is a subtype of fronto-temporal dementia where the person has difficulty speaking fluently. People with progressive non-fluent aphasia have trouble expressing themselves and following conversations. They might particularly benefit from working with a speech language pathologist, as they can provide therapy to help improve communication. Brain changes start in the temporal lobe in progressive non-fluent aphasia dementia.
- Behavioural-variant frontal dementia is a subtype of fronto-temporal dementia where the person’s behaviour, mood or personality changes. People with fronto -temporal dementia might become more apathetic, socially disinhibited, or socially unaware. They often have trouble with judgement, making poor decisions, or finding it hard to solve problems. They might develop new behavioural habits, things that they like doing repeatedly, including eating and drinking different foods or drinks.
Read more about fronto-temporal Dementia at Alzheimer’s Society of Canada, or from the Association of Fronto-Temporal Degeneration.
Lewy Body dementia
Lewy body dementia is another less common type of dementia. People with Lewy body dementia have trouble with their visuo-spatial skills, concentration and attention, movement, and falls. They frequently have abnormal movement during sleep. Their concentration and attention can fluctuate. For example, a person may be really clear in the morning and then later that same day feel muddled and confused; these fluctuations can take place over a few days as well.
Changes in movement may include developing a slowing or stiffness in the way they walk. People with Lewy body dementia sometimes see things that aren’t there (visual hallucinations), and may also believe things that are not true (delusions). People with Lewy body dementia might benefit from physiotherapy to help improve movement.
We don’t know what causes Lewy body dementia. Because of the similarities in symptoms, we think that Lewy body dementia and Parkinson’s disease are related conditions. However, in Lewy body dementia the difficulties with thinking are more prominent first, whereas in Parkinson’s disease the difficulties in movement are more prominent first.
- Read more about Lewy Body Dementia at Alzheimer’s Society of Canada.
- Read more about Lewy Body dementia from the Alzheimer’s Society of Canada.
- Read more about this type of dementia on the Lewy Body Dementia Canada website. The content was created by a carer based on his experiences caring for a parent, and his work with the broader Lewy Body dementia community. Click here to go to the website.
- Read more about Lewy Body Dementia on the Canadian Lewy Body Dementia Information website. This website was also founded by a carer and is overseen by an advisory board. Click here to go to the website.
Mixed dementia
People with mixed dementia have more than one type of dementia at the same time, often Alzheimer’s disease and vascular brain changes. People with mixed dementia have a variety of symptoms depending on the combination of dementias.
Read more about Mixed Dementia at Alzheimer’s Society of Canada.
Learn about different parts of the brain
If you are interested in understanding more about what the different parts of the brain, go to this website. You can click on different parts of a diagram of the brain and learn what that part is responsible for and challenges that may occur if that part is damaged.
