Multi-infarct dementia (MID), a common cause of dementia in the elderly, occurs when blood clots block small blood vessels in the brain and destroy brain tissue. Probable risk factors are high blood pressure and advanced age. Symptoms of multi-infarct, which often develop in a stepwise manner, include confusion, problems with recent memory, wandering or getting lost in familiar places, loss of bladder or bowel control (incontinence), emotional problems such as laughing or crying inappropriately, difficulty following instructions, and problems handling money. Usually the damage is so slight that the change is noticeable only as a series of small steps. However over time, as more small vessels are blocked, there is a gradual mental decline. Multi-infarct dementia, which typically begins between the ages of 60 and 75, affects men more often than women.
Currently there is no treatment for multi-infarct dementia that can reverse the damage that has already occurred. Treatment focuses on prevention of additional brain damage by controlling high blood pressure.
Prognosis for patients with multi-infarct dementia is generally poor. Individuals with the disease may improve for short periods of time, then decline again. However, early treatment and management of blood pressure may prevent further progression of the disorder.
The National Institute of Neurological Disorders and Stroke of the National Institutes of Health supports and conducts a wide range of research on dementing disorders such as multi-infarct dementia and on cerebrovascular disease. The goals of this research are to improve the diagnosis of these disorders and to find ways to treat and prevent them.