Causes and Heredity

There are four causes of vascular dementia:

• Blood clots that form in a vein that cause a blockage, or blood clots that come with the blood flow and cause a blockage where the vein is too narrow. These two types of blood clots often have different causes.
• Disease in the brain's very small veins (capillaries). This causes a lack of oxygen in the deep parts of the brain. That may be observed as a result of elevated blood pressure over a long period.
• Bleeding which can either be in the brain tissue (and often due to elevated blood pressure) or on the outside of the brain (which may be due to a ruptured dilated artery). Bleeding can also occur due to trauma.
• Lack of oxygen as a result of cardiac arrest, drowning, or very long-lasting seizures, for example.

Risk Factors

Factors that increase the risk for a blood clot in the heart also increase the risk of vascular dementia. That applies to elevated blood pressure, diabetes, arteriosclerosis, elevated cholesterol levels and smoking.

Hereditary Vascular Dementia – CADASIL

There are some rare types of vascular dementia that are hereditary. The most common is CADASIL (Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy). It is due to a change in a gene on Chromosome 19. Today there is a gene test that can detect 70 % of the people who have CADASIL.