Dementia is a broad category of brain diseases that cause long term loss of the ability to think and reason clearly that is severe enough to affect a person's daily functioning. For the diagnosis to be present it must be a change from how the person was previously.[1]
The most common form of dementia is Alzheimer's disease (75%).[1] Other forms include: Lewy body dementia, vascular dementia, frontotemporal dementia, progressive supranuclear palsy, corticobasal degeneration, normal pressure hydrocephalus and Creutzfeldt–Jakob disease.
Except for a few treatable types in most cases there is no cure. Cholinesterase inhibitors are often used early in the disease course; however, benefit appears to be slight.[2] Cognitive and behavioral interventions may be appropriate. Educating and providing emotional support to the caregiver is of importance. Exercise programs are beneficial with respect to activities of daily living and potentially improve dementia.[3]
Dementia becomes more common with age. While only 3% of people between the ages of 65–74 have dementia, 47% of people over the age of 85 have some form of dementia.[1] As more people are living longer, dementia is becoming more common.
In DSM-5 the decision was taken to rename the dementias as neurocognitive disorders, with various degrees of severity.
Contents [hide]
1 Signs and symptoms 1.1 Mild cognitive impairment
1.2 Early stages
1.3 Middle stages
1.4 Late stages

2 Causes 2.1 Reversible causes of dementia
2.2 Mild cognitive impairment
2.3 Fixed cognitive impairment
2.4 Slowly progressive
2.5 Alzheimer's disease
2.6 Vascular dementia
2.7 Dementia with Lewy bodies
2.8 Frontotemporal dementia
2.9 Progressive supranuclear palsy
2.10 Corticobasal degeneration
2.11 Rapidly progressive
2.12 Other conditions
3 Diagnosis 3.1 Cognitive testing
3.2 Laboratory tests
3.3 Imaging
4 Prevention
5 Management 5.1 Cognitive therapies
5.2 Medications
5.3 Pain
5.4 Eating difficulties
6 Epidemiology
7 History
8 Society and culture
9 References
10 External links

Signs and symptoms[edit]
Dementia affects the brain's ability to think, reason and remember clearly. The most common affected areas include: memory, visual-spatial, language, attention, and executive function (problem solving). Most types of dementia are slow and progressive. By the time the person shows signs of the disease, the process in the brain has been happening for a long time.It is possible for a patient to have two types of dementia at the same time. About 10% of people with dementia have what is known as mixed dementia, which is usually a combination of Alzheimer's disease and another type of dementia such as frontotemporal dementia or vascular dememtia.[4][5] Additional psychological and behavioral problems that often affect people who have dementia, include:
Disinhibition and impulsivity
Depression and/or anxiety
Agitation
Balance problems
Tremor
Speech and language difficulty
Trouble Eating or Swallowing
Delusions (often believing people are stealing from them) or Hallucinations
Memory Distortions (believing that a memory has already happened when it has not, thinking an old memory is a new one, combining two memories, or confusing the people in a memory)
Wandering or Restlessness
When people with dementia are put in circumstances beyond their abilities, there may be a sudden change to tears or anger (a "catastrophic reaction").[6]
Depression affects 20–30% of people who have dementia, and about 20% have anxiety.[7] Psychosis (often delusions of persecution) and agitation/aggression also often accompany dementia. Each of these must be assessed and treated independently of the underlying dementia.[8]
Mild cognitive impairment[edit]

In the first stages of dementia, the signs and symptoms of the disease may be subtle. Often, the early signs of dementia only become apparent when looking back in time. The earliest stage of dementia (actually, it is not even dementia, it