Symptoms of Lewy Body Dementia

People with Lewy body dementia often show more Parkinson's-like symptoms than do people with Alzheimer's. Parkinson's-like symptoms include slow movements, muscle rigidity (stiffness), tremors (shaking or trembling in one or more parts of the body), a shuffling walk, and frequent falls. People with Lewy body dementia also show Alzheimer's-like symptoms such as memory loss, confusion, impaired judgment, delusions, and apathy or depression.

Three particularly disturbing symptoms set Lewy body dementia apart from other types of dementia:

• recurrent, vivid visual hallucinations that are difficult to separate from reality

• fluctuating alertness (The person may become extremely drowsy, then suddenly have a burst of energy, making it difficult for family members to evaluate how their relative is doing.)

• severe sleep problems, including acting out one's dreams or making sharp involuntary movements (Some people with Lewy body dementia accidentally hit their caregiver or fall out of bed while sleeping.)

Diagnosis of Lewy Body Dementia

No singular test can definitively diagnose Lewy body dementia, as Lewy bodies can only be identified through autopsy. As with Alzheimer's disease, a complete diagnostic workup should be performed in order to rule out other possible causes of the person's symptoms. Fluctuating alertness, visual hallucinations, and Parkinson's-like symptoms are the most common signs of Lewy body dementia, as long as at least two of these occur along with a general decline in cognitive functioning.