What's the Difference Between Alzheimer's and Vascular Dementia?

Alzheimer’s disease and vascular dementia (sometimes called vascular cognitive impairment or vascular neurocognitive disorder) are both types of dementia. They have several symptoms and characteristics that overlap, but there are also some clear differences between the two.

If you or a loved one is diagnosed with either condition, this broad overview of the main differences between the two can help you get a grasp on the differences. Keep reading for more detailed information.

Prevalence

Vascular dementia: Statistics vary widely as to the prevalence of vascular dementia, but it’s estimated it accounts for close to 10% of dementia cases. Among older people with dementia, about 50% have signs of vascular dementia.

Alzheimer’s: Alzheimer's disease is by far the most common kind of dementia. There are more than 5 million Americans with Alzheimer’s disease.

Causes

Vascular dementia: Vascular dementia is often caused by an acute, specific event such as a stroke or transient ischemic attack in which blood flow to the brain has been interrupted. It also can develop more gradually over time from very small blockages or the slowing of blood flow.

Alzheimer’s: While there are several ways to decrease the chance of developing Alzheimer’s, including exercise and maintaining an active mind, what causes Alzheimer’s to develop isn't fully understood. There appear to be many contributing components, such as genetics, lifestyle, and other environmental factors.

Risk Factors

Vascular dementia: Common risk factors include coronary heart disease, peripheral artery disease, diabetes mellitus, high blood pressure, and high cholesterol.

Alzheimer’s: Risk factors include age, genetics (heredity), and general health.

Symptoms

The two conditions have some differences in cognitive symptoms and physical symptoms.

Cognition

Vascular dementia: Cognitive abilities often seem to decline suddenly in relation to an event like a stroke or a transient ischemic attack (TIA) and then remain stable for a time. These changes are often described as step-like since in between them, brain functioning may hold steady.

Alzheimer’s: While cognition can vary somewhat in Alzheimer’s, the person’s ability to think and use his memory gradually declines over time. There is not usually a sudden, significant change from one day to the next.

Walking and Physical Movement

Vascular dementia: Vascular dementia is often accompanied by some physical challenge. If a person has a stroke, they may have limited movement on one side of her body. Both the cognitive and physical impairments related to vascular dementia usually develop at the same time since they are often the result of a sudden condition like a stroke.

Alzheimer’s: Often, mental abilities like memory or judgment decline initially, and then as Alzheimer's progresses into the middle stages, physical abilities like balance or walking show some deterioration. 

Diagnosis

Vascular dementia: Several tests can help evaluate your loved one's memory, judgment, communication and general cognitive ability. Along with those tests, an MRI can often clearly identify a specific area in the brain where a stroke affected the brain.

Alzheimer’s: Similar cognitive tests are used to evaluate brain functioning, but Alzheimer's is often diagnosed by ruling out other causes, rather than being able to pinpoint the diagnosis through a brain scan.

There's no test to diagnose Alzheimer's at this time, so physicians generally eliminate other reversible causes of confusion such as vitamin B12 deficiency and normal pressure hydrocephalus, as well as other types of dementia or delirium.

Disease Progression

Vascular dementia: Since there is such a variety of causes and different amounts of damage, it's difficult to predict survival time for vascular dementia. Progression of vascular dementia depends on a number of factors including the extent of the damage in the brain, in addition to your overall health condition.

Alzheimer’s: Indivduals with Alzheimer's disease have a median age at death of 84.6 years old. The survival after the beginning of symptoms is an average of 8.4 years.

A Word From Verywell

Learning the differences between vascular dementia and Alzheimer's disease can help you better understand what to expect from a diagnosis. 

Additionally, while there are clear differences between the two diseases, research has found that some similar strategies can be used to reduce their risk. These include a heart-healthy diet and physical activity.