After Alzheimer’s disease, the most common cause of significant memory loss is vascular dementia—a disorder often resulting from a series of tiny strokes (known as infarcts) that destroy brain cells. Each small infarct may be inconsequential alone, but the cumulative effect of many infarcts can destroy enough brain tissue to impair memory, language and other intellectual abilities. Other causes include cerebral amyloid angiopathy, in which the amyloid protein is deposited along blood vessels and causes them to rupture, and vasculitis, in which blood vessels become inflamed. This results in narrowing of the blood vessels and a weakening of the blood vessel walls, a risk factor for stroke.
Symptoms of vascular dementia often develop suddenly, and they are not limited to brain functions. Noncognitive hallmarks of vascular dementia include loss of bladder or bowel control (incontinence), a mask like facial expression, and weakness or paralysis on one side of the body.
Vascular disease accounts for 10 to 20 percent of all dementia cases. Vascular dementia can also result from vasculitis caused by lupus and other collagen-vascular diseases—and may be at least partially reversible in these conditions—as well as from a major stroke. Many people suffer from vascular dementia as a result of chronic high blood pressure, diabetes or coronary heart disease (a narrowing of the coronary arteries that reduces blood flow to the heart).  People who survive a cardiac arrest can also suffer from memory deficits.
Drugs approved to treat Alzheimer’s are not approved for use in folks with vascular dementia, and the evidence that they are beneficial is weak. An article published in Neurological Research, for example, concluded that the Alzheimer’s drugs donepezil (Aricept), rivastigmine (Exelon) and galantamine (Razadyne) appear to have benefits in people who have vascular dementia alone and in those who have it in conjunction with Alzheimer’s disease but because the diagnosis of vascular dementia is more difficult to make than Alzheimer’s disease, some individuals diagnosed with vascular dementia in those trials may have had only Alzheimer’s disease.
This information provided by Health After 50.