What is Dementia?
Dementia is not a single disease. It is a general term used to describe a group of symptoms that occur when the brain is affected by certain conditions. These symptoms often begin with mild memory loss but can progress to confusion, disorientation, and difficulty recognising familiar people or places. Over time, individuals with dementia may lose the ability to carry out daily tasks independently.
Common Types of Dementia
Some types of dementia are more common and better understood than others. Here are the main ones:
Alzheimer’s Disease
Alzheimer’s is the most common cause of dementia, responsible for around 50 to 70 percent of cases. The disease begins to damage the brain years before symptoms appear. It gradually affects memory, decision-making, and the ability to perform simple tasks.
As Alzheimer’s progresses, brain cells break down and die, and brain scans often show significant shrinkage in brain tissue. The condition is currently incurable. Medication can help manage symptoms, but there is no treatment that can stop or reverse the disease.
Alzheimer’s usually affects people over the age of 65. Those over 80 may survive only three to eight years after diagnosis, although some younger individuals live ten years or more with the condition.
Vascular Dementia
Vascular dementia is the second most common type and affects around 150,000 people in the UK. It is caused by reduced blood flow to the brain, often following a stroke. Not all strokes result in dementia, but having one increases the risk of future strokes, which in turn raises the likelihood of developing vascular dementia.
Symptoms can appear suddenly or gradually, depending on the cause and severity of the damage.
Dementia with Lewy Bodies
This type of dementia is caused by the build-up of abnormal protein deposits, known as Lewy bodies, inside brain cells. It shares symptoms with both Alzheimer’s and Parkinson’s, including memory problems, movement difficulties, and changes in alertness.
Lewy bodies interfere with chemical signals in the brain and contribute to the gradual death of nerve cells, leading to ongoing cognitive decline.
Frontotemporal Dementia
Frontotemporal dementia (FTD) occurs when the frontal and temporal lobes of the brain are damaged. These areas are responsible for behaviour, emotions, and language. Although FTD is less common overall, it is a leading cause of dementia in people under 65.
Symptoms often include personality changes, difficulty with language, and inappropriate social behaviour rather than memory loss at first.
Other Causes of Dementia
Dementia-like symptoms can also appear in the later stages of diseases such as HIV/AIDS, Parkinson’s, and Huntington’s. Long-term alcohol misuse can lead to a condition that mimics dementia, though this may be partially reversible and is not classified as true dementia.
Clearing Up the Confusion
Because Alzheimer’s is the most common form of dementia, many people use the terms interchangeably. In reality, Alzheimer’s is one of many types. Understanding the distinction is important, especially as global dementia cases are expected to reach 75.6 million in the next 20 years, with over half of those caused by Alzheimer’s.
In Summary
Greater awareness of the different forms of dementia can lead to earlier diagnosis, better care, and stronger support for families and carers. As the number of people affected continues to rise, improving public understanding is more important than ever.
