Dementia is a syndrome due to disease of the brain, usually chronic, characterized by a
progressive, global deterioration in intellect including memory, learning, orientation, language, comprehension and judgment. It is one of the major causes of disability in later life.
Dementia mainly affects older people, however, between 2% and 10% of all cases start before the age of 65. After this, the prevalence doubles with every five year increment in age.
