Understanding and treating multi-infarct dementia.

MID is a controversial entity responsible for at least 15 to 20 per cent of dementia in the elderly. Clinical manifestations include dementia with abrupt onset, step-wise progression, and focal neurologic signs and symptoms. Infarcts are scattered through the brain involving both subcortical and cortical regions secondary to hypertensive atherosclerotic cerebrovascular disease. Diagnosis is based on the presence of dementia with both cognitive and motor sequelae of stroke as suggested by an elevated "ischemic score." Neuro-imaging studies, while not particularly helpful in differential diagnosis, have identified a population with white matter hypodensity without clinical signs of dementia who may serve as a presymptomatic at-risk group, allowing for studies of the pathogenesis of stroke-related dementia. Management of the cognitive difficulties of MID is similar to that of other forms of dementia. Therapy is directed at patients with modalities that will reduce the likelihood of further vascular insults. This would include treatment of hypertension, cessation of smoking, avoidance of excessive alcohol intake, and use of aspirin for patients with atherothrombotic disease. Medical measures have been shown to be effective in reducing the occurrence of stroke. Further studies are needed to assess the benefits of these measures for MID exclusively.