Dementia with Lewy bodies: disease concept and genetics.

Dementia with Lewy bodies (DLB) was first recognized as a clinicopathological entity about 20 years ago. It is the second most-common degenerative dementia after Alzheimer's disease. Clinically, DLB differs from Alzheimer's disease in that disease symptoms are prone to fluctuate and patients often suffer from visual hallucinations, while short-term memory is relatively preserved. As many as 70% of patients have parkinsonism and up to 50% are sensitive to the extrapyramidal side effects of neuroleptic drugs. About 3 million Europeans will be affected by DLB in 2020 if no cure or effective treatment is found. This article reviews the current disease concept, as well as existing problems concerning classification and delineation of DLB from other conditions with dementia. The literature on genetic findings in this complex disease is critically discussed.