It is the most common cause of dementia in old age people. But differentiating it with vitamin deficiency. It has been found that 5%of population of 65years old people are facing this complaint globally.
The exact cause of the disease is yet unknown. It has been found that there are the dominant alleles in genes is responsible for the disease transmission. Also it has found that many cases of Vitamin- B12 deficiency is misdiagnosed as Alzheimer's disease. Some recent researches has found that the more exposure to electromagnetic waves directly to brain would be also reason which is by means of constantly exposing to the computer monitor and in case of having electronic caller machines.
In this disease the brain cortex is formed with plaque which is like amyloid structure which found by biochemical process. The plaques formed in the brain could be found by imaging technique. But only can confirmed during autopsy.
Initially the old people have the problem of memory loss and it would be both short term and long term memory loss. It is more pronounced in short term memory loss. Later they have difficulty to calculating the exact position and length of the place. Soon there seemed to have derangement in the intellectual facility. The persons later would become aggressive or depressed it varies to person to person. When there seems to have intellectual deformity the disease become to pronounce externally.