Dementia is an acquired global impairment of memory, intellect and personality without impairment of consciousness. It is not a specific diagnosis in itself, but is a syndrome (a group of symptoms that collectively indicate or characterize a disease, psychological disorder, or other abnormal condition). It is always of long duration, at least 6 months, is usually progressive and usually irreversible at the current stage of knowledge.

The most common cause of dementia is Alzheimer’s disease. Other important types are:

  • vascular dementia
  • Lewy Body dementia
  • frontotemporal dementia
  • head injury
  • alcohol abuse