What is Dementia?
Dementia is an overall term for several different disorders that affect the brain, including Alzheimer's disease. In people who have dementia, the brain cells progressively degenerate, which can affect memory, cognition (thinking), behavior and mood. These disorders are also known as neurodegenerative disorders.
Besides Alzheimer's disease, the other dementias are vascular dementia, Lewy body dementia and a spectrum of frontotemporal dementias.
Dementia is more common as we age, though it can occur in young people as well. Some form of cognitive impairment affects about 15% of the population over age 65. Here is a brief description of the main types of dementia.
Alzheimer's Disease
Alzheimer's disease is the most common form of dementia, accounting for about 64% of dementia cases. It is a progressive and fatal disorder that destroys brain cells. People with Alzheimer's disease have trouble remembering things, making decisions and performing everyday tasks. There is no cure, but there is a large amount of research occurring around the world to try to find effective treatments and possibly even prevent the disease.
Vascular Dementia
Vascular dementia accounts for about 20% of dementias. It is a disorder in which the cells in the brain are deprived of the oxygen they need to stay healthy. Vascular dementia is commonly but not exclusively caused by stroke.
Lewy Body Dementia
Lewy body dementia accounts for 5% to 15% of dementias. In Lewy body dementia, abnormal deposits of a protein collect in the brain's nerve cells. This interrupts the brain's messages, affecting thinking and movement.
Frontotemporal Dementias
Frontotemporal dementias are a group of rare disorders that affect the frontal and temporal lobes of the brain. They are generally associated with personality and behavior changes. One example is Pick's disease, in which the person's personality changes, making them either more withdrawn or more disinhibited.
For more information:
Sunnybrook Health Sciences Centre, dementia: http://sunnybrook.ca/content/?page=bsp-dementias-home
Baycrest, dementia: http://www.baycrest.org/MemoryandAging/
Toronto Dementia Research Alliance: http://www.tdra.ca
Brain Canada: http://www.braincanada/ca/
Alzheimer Society of Toronto: http:/www.alzheimertoronto.org