Dementia is not a specific disease but is rather a general term for the impaired ability to remember, think, or make decisions that interferes with doing everyday activities. The most common type of dementia is Alzheimer’s disease.
The most common types of dementia are:
- Alzheimer’s disease
- Vascular dementia: Caused by reduced blood flow to the brain, which damages and eventually kills brain cells.
- Lewy body dementia: Associated with abnormal deposits of a protein called alpha-synuclein in the brain. These deposits, called Lewy bodies, affect chemicals in the brain whose changes, in turn, can lead to problems with thinking, movement, behavior, and mood.
- Fronto-temporal dementia: This type of dementia most often leads to changes in personality and behavior because of the part of the brain it affects: the frontal and temporal lobes of the brain.
- Mixed dementia: When more than one type of dementia is present in the brain at the same time.
- Reversible causes: People who have dementia may have a reversible underlying cause such as side effect of medication, increased pressure in the brain, vitamin deficiency, and thyroid hormone imbalance. Medical providers should screen for reversible causes in patients who are concerning for dementia.
Over 60% of dementia patients live in low- and middle-income countries, according to the World Health Organization, which estimates that there are about 55 million cases of dementia globally. It is anticipated that this figure will increase to 78 million in 2030 and 139 million in 2050 due to the fact that the proportion of older people in the population is rising in almost every country. It's essential to remember that dementia is not a natural aspect of ageing, even though it primarily affects older persons (particularly those over 65). Younger persons can get dementia.
The life expectancy of those who suffer from dementia, including Alzheimer's, is significantly reduced. A person with Alzheimer's typically lives 4 to 8 years after their diagnosis, according to the Alzheimer's Association. However some people live with dementia for twenty years.
Depending on the underlying cause, the treatment option is selected. Although there is no known cure for neurodegenerative dementias like Alzheimer's, there are medications which can help protect the brain or control symptoms like anxiety or behavioural disturbances. There is ongoing research to develop more treatment options.
