Causes of Dementia There is no single cause of dementia and as we learn more and more about the diseases causing dementia, it seems unlikely that there is a single cause. It is more likely that a range of risk factors can increase the risk of someone developing dementia.

Alzheimer's Disease Risk Factors

• Demographic Risk Factors - Age is most obvious of these, with the likelihood of Alzheimer's increasing after the age of 60. Also, more women than men seem to develop Alzheimer's, but this could simply be that women tend to live longer than men.
• Genetic Risk Factors - Between 25-50% of people with Alzheimer's have a family history of the disease. Early-onset Alzheimers (under the age of 65) is very common in families. Studies have shown that Alzheimer's disease is related to a gene called ApoE - about 40% of people with Alzheimer's disease appear to have a faulty version of this gene.
• Health Risk Factors - Head injuries seems to increase the likelihood of Alzheimer's disease. People who have had head injuries have a protein in their brains (Beta amyloid) which the ApoE gene normally removes. If the ApoE gene isn't working properly, this protein remains in the brain and appears to kill of nerve cells in the brain, resulting in dementia. Smoking, fat intake and lifestyle can affect this process and so increase the chances of dementia developing.

Vascular dementia risk factors

• Genetic Risk Factors - Some studies have pointed to gene which increase the chances of strokes occuring, and therefore increase the chance of dementia following a stroke.
• Health Risk Factors - Diabetes, alchohol abuse, obesity, smoking and hypertension can all increase the chance of a stroke, and so increase the chance of dementia developing.

If you feel that someone you know is showing some of the signs of dementia, you must speak to your doctor as soon as possible. Many of the above symptoms can be signs of other medical conditions (like delerium, amnesia or depression) - you should not assume a certain symptom is a sure sign of dementia - only the doctor can diagnose dementia.