What Causes Dementia?

Broadly speaking, dementia is caused by the death of brain cells due to injury or disease, but there are many different types of dementia, all of which affect the brain in different ways, so what causes dementia and what are the different types of dementia?

What Causes Dementia?

Alzheimer’s disease is one of the most common causes of dementia. The disease causes a protein build up in the brain that slowly destroys brain cells.

Research has also shown that there is a shortage of neurotransmitter chemicals in the brains of those suffering the effects of Alzheimer’s disease.

Vascular dementia is the second most common cause of dementia and is usually caused by one major stroke, or many small “mini strokes”. This type of dementia occurs as a result of an interruption of blood supply to the brain—a lack of oxygenated blood causes brain cells to die in the affected area of the brain.

Dementia with Lewy bodies is very similar in characteristics to Alzheimer’s disease and vascular dementia.

The name refers to the “Lewy bodies”, small protein deposits that cause disruptions to neurotransmitters in the brain.

Patients with Lewy bodies dementia may also go on to develop Parkinson’s disease as the two conditions present in very similar ways.

Korsakoff’s syndrome is a type of dementia caused by excessive alcohol consumption over a period of many years. Although not exactly a form of dementia, the effects of alcoholism cause dementia-like symptoms.

Fronto-temporal dementia is a rare form of dementia that includes dementia caused by Pick’s disease, motor neuron disease, and frontal lobe degeneration.

This type of dementia is caused by a gene abnormality and is normally inherited, although in rare cases, the disease is non-inherited and the cause is unknown.

Neimann-Pick disease type C is an inherited disease and is caused by a build up of cholesterol. It is most common in school-age children and there is currently no treatment or cure.

Creutzfeldt-Jakob disease (CJD) is caused by an infection that attacks the central nervous system and the brain. The infection causes proteins called “prions” to form abnormal clusters, which leads to spongiosis (holes) in the brain and the symptoms of dementia.

What Causes Dementia in Rarer Cases?

Dementia caused by Parkinson’s disease, CJD, Huntingdon’s disease and fronto-temporal dementia are all relatively rare, but another example of a rare form of dementia is Binswanger’s disease.

This type of dementia is thought to be associated with long-term hypertension, although the exact cause is as yet unknown.

Other Causes of Dementia

The symptoms of dementia can also appear as a result of brain injuries and brain tumors as well as a number of health problems including a vitamin B12 deficiency, an under-active thyroid, normal pressure hydrocephalus, multiple sclerosis, HIV-related cognitive impairment, and various learning difficulties.

It is very important to remember that the symptoms of dementia can have more than one underlying cause and even if a patient has one type of dementia such as Alzheimer’s disease, they may also have another condition that is causing dementia related symptoms.