Multi-infarct dementia

• Alternative Names

  MID

• Causes, incidence, and risk factors

  Multi-infarct dementia (MID) is the most common form of vascular dementia, and the second most common cause of dementia (after Alzheimer's disease) in people over age 65.

  An estimated 10 - 20% of all dementias are caused by strokes. MID affects men more often than women. The disorder usually affects people between ages 55 and 75.

  "Multi-infarct" means that many areas in the brain have been injured due to a lack of blood.

  Risk factors for MID include a history of:

  • Hardening of the arteries (atherosclerosis)
  • High blood pressure (hypertension)
  • Smoking
  • Stroke

  Some research suggests that MID may cause Alzheimer's disease or make it get worse faster. MID may be misdiagnosed as Alzheimer's, or may be found along with Alzheimer's.

• Symptoms
  • Confusion at night
  • Decreased ability to function independently
  • Decreased interest in daily living activities
  • Difficulty making judgments
  • Extreme emotional disturbance (agitation)
  • Frustration, depression, anxiety, stress, and tension from loss of mental function
  • Inability to be spontaneous
  • Lack of emotion
  • Memory loss
  • Numbness or tingling
  • Slowly worsening memory loss (dementia) and:
    • Confusion, disorientation
    • Decline in many brain functions that gets worse
    • Difficulties with attention, concentration, judgment, and behavior
    • Difficulty thinking
    • False beliefs (delusions)
    • Hearing sounds or seeing things that are not there (hallucinations)
    • Personality changes
    • Problems with language (aphasia)
    • Uncoordinated or weak movements
  • Swallowing difficulty
  • Sudden involuntary laughing or crying
  • Urinary incontinence
  • Withdrawal from social interaction
    • Inability to interact in social or personal situations
    • Inability to keep a job
• Signs and tests

  Diagnosis rules out other causes of dementia, including dementia due to metabolic causes.

  Signs of multi-infarct dementia include:

  • Abnormal reflexes
  • Local nervous system (neurologic) signs (on the modified Hachinski ischemia scale)
  • Past stroke or high blood pressure
  • Periods of quick worsening alternating with stable periods of very little change
  • Quick onset
  • Weakness or loss of function on one side, one area, or many areas

  Tests may include:

  • Head CT scan
  • MRI of the brain
• Treatment

  There is no treatment for MID. The goal is to control symptoms and correct risk factors such as high blood pressure and high cholesterol. The health care provider may recommend other treatments.

  DIAGNOSIS AND TREATMENT

  The diagnosis and treatment environment should be pleasant, comfortable, nonthreatening, and physically safe. Some patients may need to stay in the hospital for a short time. The health care provider will try to find the cause and treat it.

  Stopping or changing medications that worsen or cause confusion may improve mental function. Medications that may cause confusion include:

  • Anticholinergics (including antidepressants such as amitriptyline or imipramine)
  • Central nervous system depressants
  • Cimetidine
  • Lidocaine
  • Pain relievers

  Disorders that may contribute to confusion include:

  • Anemia
  • Heart failure
  • Infections
  • Low oxygen (hypoxia)
  • Mental conditions such as depression
  • Nutritional disorders
  • Thyroid disorders

  Treating medical and mental disorders often greatly improves function.

  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:

  • Antipsychotics (olanzapine, quetiapine)
  • Beta blockers
  • Serotonin-affecting drugs (trazodone, buspirone, or fluoxetine).

  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.

  LONG-TERM TREATMENT

  The following may be helpful in caring for a person with MID:

  • Adult day care
  • Adult protective services
  • Boarding homes
  • Community resources
  • Convalescent homes
  • Family counseling
  • Homemakers
  • In-home care
  • Visiting nurses or aides
  • Volunteer services

  Other care tips:

  • Keep familiar objects and people around.
  • Leave lights on at night.
  • Stick to a simple schedule of activities.
  • Use behavior modification to help control unacceptable or dangerous behaviors.
  • Use reality orientation with environmental cues to help reduce disorientation.

  Seek legal advice early in the course of the disorder. Advance directives, power of attorney, and other legal actions may make it easier to make ethical decisions regarding the care of the person with MID.

• Expectations (prognosis)

  The disorder gets worse over time.

  Death may occur from:

  • Heart disease
  • Pneumonia or other infection
  • Stroke
• Complications
  • Heart disease
  • Infections anywhere in the body
  • Loss of ability to function or care for self
  • Loss of ability to interact
  • Pneumonia
  • Reduced lifespan
  • Side effects of medications
  • Stroke
• Calling your health care provider

  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.

  Treatment that is started within 3 hours after symptoms begin may reduce damage caused by strokes.

• Prevention

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

  • Controlling high blood pressure
  • Controlling weight
  • Reducing saturated fats and salt in the diet
  • Treating related disorders

Review Date: 2/13/2008

Reviewed By: Luc Jasmin, MD, PhD, Departments of Anatomy & Neurological Surgery, University of California, San Francisco, CA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.