But nevertheless, the major hypothesis is still very interesting for the possibility of prevention of the disease. The vaccines are designed to attack the characteristic brain plaques of Alzheimer's. There is still some debate over whether the amyloid plaques are the cause of Alzheimer's dementia. The final outcome of the vaccine studies in humans should either prove or disprove the amyloid plaque theory as the cause of the disease. Alzheimer s causes progressive memory loss and dementia as well as weight loss, incontinence and difficulty in physical tasks like walking with steadiness.
Many patients enter a vegetative state.
From the onset of symptoms until death, the average is 8 years but may range from 3 to 20 years, according to the Alzheimer s Association. Although there is no cure for Alzheimer's, there are currently three drugs approved to treat symptoms of the disease. CNN Medical Correspondent Rhonda Rowland contributed to this report. Pages will open in a new browser window External sites are not endorsed by CNN Interactive. All Rights Reserved.