Multi-infarct dementia


Multi-infarct dementia (MID) is a form of dementia caused by a series of small strokes.

Dementia is a loss of brain function that occurs with certain diseases. It affects memory, thinking, language, judgment, and behavior.

Alternative Names

MID; Dementia - vascular; Dementia - poststroke


Multi-infarct dementia (MID) is the second most common cause of dementia (after Alzheimer's disease) in people over age 65. MID affects men more often than women. The disorder usually affects people between ages 55 and 75.

MID is caused by a series of small strokes.

Risk factors for MID include a history of:

See also: Stroke risk factors and prevention

Symptoms of dementia in any one person may be caused by either Alzheimer's disease or MID. The symptoms for each problem are very similar, and MID may be a risk factor for Alzheimer's disease.


Symptoms may develop gradually or may progress after each small stroke.

The symptoms of the disorder may begin suddenly after each stroke. Some people with MID may appear to improve for short periods of time, then decline after having more silent strokes.

The early symptoms of dementia can include:

As the dementia becomes worse, symptoms are more obvious and interfere with the ability to take care of yourself. The symptoms may include:

Any of the neurologic problems that occur with a stroke may also be present.

Exams and Tests

Tests may be ordered to help determine whether other medical problems could be causing dementia or making it worse, such as:

Neuropsychological testing is often helpful to find out what parts of thinking have been affected, and to guide other tests.

Tests that can show evidence of previous strokes in the brain may include:


There is no treatment to turn back damage to the brain caused by small strokes.

An important goal is to control symptoms and correct risk factors such as high blood pressure, smoking, and high cholesterol to prevent future strokes.

The goals of helping someone with dementia in the home environment are to:

See dementia - homecare for information about taking care of a loved one with dementia.

Medications may be needed to control aggressive, agitated, or dangerous behaviors. The health care provider will usually prescribe these medicines in very low doses and adjust the dose as needed. Such medications may include:

Medications used to treat Alzheimer's disease have not been shown to work for MID.

Hearing aids, glasses, or cataract surgery may be needed if the person has sensory problems.

Outlook (Prognosis)

Some improvement may occur for short periods of time, but the disorder will generally get worse over time.

Possible Complications

Complications include the following:

When to Contact a Medical Professional

Call your health care provider if symptoms of vascular dementia occur. Go to the emergency room or call the local emergency number (such as 911) if there is a sudden change in mental status. This is an emergency symptom of stroke.


Control conditions that increase the risk of hardening of the arteries (atherosclerosis) by:

See also: Stroke risk factors and prevention


Brewer JB, Gabrieli JDE, Preston AR, Vaidya CJ, Rosen AC. Memory. In: Goetz CG, ed. Textbook of Clinical Neurology. 3rd ed. Philadelphia, Pa: Saunders Elsevier;2007:chap 5.

DeKosky ST, Kaufer Di, Hamilton RL, Wolk DA, Lopez OL. The dementias. In: Bradley WG, Daroff RB, Fenichel GM, Jankovic J, eds. Neurology in Clinical Practice. 5th ed. Philadelphia, Pa: Butterworth-Heinemann; 2008:chap 70.

Review Date: 2/16/2012
Reviewed By: Luc Jasmin, MD, PhD, Department of Neurosurgery at Cedars-Sinai Medical Center, Los Angeles, and Department of Anatomy at UCSF, San Francisco, CA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Health Solutions, Ebix, Inc.
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