Vascular dementia: causes, symptoms, diagnosis and management

Causes and pathology

Brain cells rely on a continuous supply of oxygen and nutrients delivered by the vascular system. When arteries or small blood vessels are blocked, narrowed, or damaged, regions of brain tissue may suffer ischemia (reduced blood flow) or infarction (cell death). Common vascular causes include stroke (large vessel occlusion), many small lacunar infarcts from small vessel disease, and chronic reduced perfusion related to heart disease.

• Major risk factors: high blood pressure, diabetes, smoking, high cholesterol and atrial fibrillation.
• Underlying mechanisms: thromboembolism, atherosclerosis, and small-vessel degeneration.

Symptoms and clinical course

Symptoms vary depending on the location and extent of vascular injury. Typical features include slowed thinking, impaired planning and judgment, difficulties with attention and executive function, and variable memory impairment. Onset may be sudden after a stroke or progress in a stepwise pattern with further vascular events. Focal neurological signs (for example weakness or speech difficulties) are more common than in some other dementias.

Diagnosis and management

Diagnosis combines clinical assessment, cognitive testing and brain imaging (CT or MRI) to identify vascular lesions. Blood tests and cardiac evaluation help find treatable causes. There is no cure, so management focuses on reducing further vascular damage: blood-pressure control, diabetes management, smoking cessation, lipid-lowering therapy and antiplatelet or anticoagulant treatment when indicated. Some symptomatic medications and cognitive rehabilitation may help function and quality of life.

Prevention, prognosis and distinctions

Preventive control of vascular risk factors is the most effective strategy to lower incidence and slow progression. Prognosis varies: some people remain stable for years, while others decline in a stepwise fashion after recurrent events. Vascular dementia often coexists with degenerative conditions — a situation called mixed dementia — which can complicate diagnosis and treatment. For further clinical guidance see blood flow and stroke resources, brain imaging guides and information on protecting brain cells.