What causes dementia?
Dementia is caused by a number of diseases which destroy nerve cells and damage the brain, as outlined below.
Alzheimer’s disease
Alzheimer’s disease is the most common cause of dementia. It destroys brain cells and nerves, disrupting the transmitters that carry messages in the brain, particularly those responsible for storing memories.
Vascular dementia
Vascular dementia occurs where blood vessels are damaged, the supply of oxygen to the brain fails and as a result, brain cells die. The symptoms of vascular dementia can occur either suddenly, following a stroke, or over time, through a series of small strokes. Vascular dementia accounts for 20%-30% of all cases of dementia.
Dementia with Lewy bodies
Dementia with Lewy bodies is similar to Alzheimer’s disease in that it is caused by deteriorating and dying nerve cells in the brain. It takes its name from abnormal deposits of protein
-Lewy bodies - in the nerve cells of the brain. It may account for around 10% of all cases of dementia. Approximately, half the people with Lewy body disease also develop signs and symptoms of Parkinson’s disease.
Fronto-temporal dementia
In fronto-temporal dementia - including Pick’s disease - damage is usually concentrated in the front part of the brain. In the beginning, personality and behaviour are more affected than memory.
Rarer causes of dementia
There are many other rarer causes of dementia, such as alcohol-related dementia and dementia due to HIV/AIDS.
