Chapter 11-8: Multi-infarct Dementia (Vascular Dementia, VaD)

TEXTBOOK PRESENTATION

The onset of VaD may be abrupt or gradual. The patient usually has risk factors for, or has previously diagnosed, vascular disease. The patient may have gait disturbance during the neurologic exam.

DISEASE HIGHLIGHTS

1. Generally considered to be the most common cause of dementia after AD.

2. Most common in patients with risk factors for vascular disease or an embolic stroke.

3. Patients have dementia and evidence that cerebrovascular disease has caused the dementia.

   1. A classic but insensitive clue is a “step-like deterioration” related to intermittent CVAs.

   2. Other clues are a focal neurologic exam or evidence of strokes, white matter changes, or atrophy on neuroimaging.

4. Symptoms of VaD include gait disturbance, urinary symptoms, and personality changes.

EVIDENCE-BASED DIAGNOSIS

1. The DSM-5 criteria for the clinical diagnosis of VaD are:

   1. The criteria are met for major or mild neurocognitive disorder.

   2. The clinical features are consistent with a vascular etiology, as suggested by either of the following:

      1. Onset of the cognitive deficits is temporally related to one or more cerebrovascular events.

      2. Evidence for decline is prominent in complex attention (including processing speed) and frontal-executive function.

   3. There is evidence of the presence of cerebrovascular disease from history, physical exam, and/or neuroimaging considered sufficient to account for the neurocognitive deficits.

   4. The symptoms are not better explained by another brain disease or systemic disorder.

2. Features consistent with the diagnosis of VaD are:

   1. Exaggeration of deep tendon reflexes

   2. Extensor plantar response

   3. Gait abnormalities (consider history of unsteadiness and frequent, unprovoked falls)

   4. Pseudobulbar palsy (pathologic laughing, crying, grimacing; and weakness of the muscles associated with cranial nerves V, VII, IX, X, XI, and XII)

   5. Focal neurologic signs

3. The actual diagnosis of VaD is complicated by the presence of multiple different criteria.

4. The Hachinski Ischemic Score seems to be a clinically useful test for determining whether ischemic disease is playing a role in a patient’s dementia.

   1. In the score, two points are given for each of the following features:

      1. Abrupt onset

      2. Fluctuating course

      3. History of stroke

      4. Focal neurologic signs and symptoms

   2. One point is given for each of the following features:

      1. Stepwise deterioration

      2. Nocturnal confusion

      3. Preservation of personality

      4. Depression

      5. Somatic complaints

      6. Emotional lability

      7. Hypertension

      8. Atherosclerosis

   3. A score of > 7 carries an LR+ of 8.3 for differentiating VaD from AD. The score performs less well for differentiating AD or VaD from a mixed dementia.

TREATMENT

1. Behavioral, pharmacologic, and surgical means of modifying risk factors for cerebrovascular disease and preventing recurrent vascular events should be used.

2. Behavioral interventions include smoking cessation and dietary intervention to decrease vascular risk.

3. Pharmacologic interventions include treatment of hypertension and diabetes mellitus, treatment of hypercholesterolemia (to an LDL < 70 mg/dL), aspirin therapy, and anticoagulation when indicated.

4. Surgical therapy includes carotid endarterectomy when indicated.