The second most common form of dementia is vascular dementia. Brain cells require a consistent supply of oxygen and nutrients from the blood to function and be healthy. The vascular system is a network of blood vessels that supplies the brain tissues with blood. When these blood vessels become obstructed or damaged, blood cannot get to the cells in the brain. Without a consistent blood supply, the brain cells begin to die.
An ischemic or hemorrhagic stroke can cause patients to develop a type of vascular dementia called post-stroke dementia. Individuals can develop forms of vascular dementia called single-infarct and multi-infarct dementia if they experience a series of smaller strokes rather than a single severe one. When the smallest blood vessels in the brain become twisted and stiff to the degree that they restrict blood flow, it is referred to as small vessel disease. Individuals affected by small vessel disease in their brain may develop the most common type of vascular dementia: subcortical dementia.