Vascular dementia is the second most common form of dementia in the United Kingdom, and accounts for roughly 20% of all cases of dementia.
For the human brain to function effectively, it requires a consistent supply of oxygen-rich blood, which it receives through a network of blood vessels called the vascular system. In vascular dementia, the blood vessels in the brain become damaged, resulting in reduced blood supply to certain parts of the brain.
In this condition, changes to the vascular system are usually caused by either a series of very small strokes, or a condition called small vessel disease which damages the tiny blood vessels in the centre of the brain. Because these changes often occur suddenly, the progression of vascular dementia is different from many other forms of dementia such as Alzheimer’s disease. Cognitive decline often occurs in a step-wise pattern with periods of stable functioning followed by a sudden drop which then stabilises to a lower overall level of functioning.
Common symptoms of vascular dementia include:
- Difficulties with concentration and communication
- Memory problems (although often not to the extent seen in Alzheimer’s disease)
- Symptoms of stroke such as physical weakness or paralysis; periods of acute confusion; and depression.
In some people, vascular changes occur alongside Alzheimer’s disease, causing a mixed-form of dementia which shares features of the two conditions. Mixed dementia tends to be more common in older people.