Epidemiology and Classification of Dementia

Dementia is not a natural consequence of aging or even extreme forgetfulness. It is a generally progressive chronic syndrome in which patients experience a deterioration in memory, thinking, behavior, and the ability to perform everyday activities.29 Dementia is described in the International Classification of Disease version 10 (ICD-10) as:

A syndrome due to disease of the brain, usually of a chronic or progressive nature, in which there is a disturbance of multiple higher cortical functions, including memory, thinking, orientation, comprehension, calculation, learning capacity, language, and judgement. Consciousness is not clouded. The impairments of cognitive function are commonly accompanied, and occasionally preceded, by deterioration in emotional control, social, behavior, or motivation. This syndrome occurs in Alzheimer’s disease, in cerebrovascular disease, and in other conditions primarily or secondarily affecting the brain.30

Nearly 10 million individuals are diagnosed with new cases of dementia each year and that number is expected to increase with increasing life expectancy worldwide.29 The economic costs in the United States associated with dementia were approximated to be $818 billion in 2015.29