Lewy Body Disorders.

Dementia syndromes associated with Lewy bodies are subdivided into dementia with Lewy bodies (DLB), an underdiagnosed cause of dementia in the elderly, and Parkinson disease with dementia (PDD), cognitive impairment appearing in people diagnosed with Parkinson disease. Their neuropathologic substrates are the widespread distribution of aggregates of the protein α-synuclein in neurons in cortical brain regions, accompanied by variable Alzheimer pathology. Clinical features of DLB and PDD include distinctive changes in cognition, behavior, movement, sleep, and autonomic function. Diagnostic criteria for DLB and PDD incorporate these features. Current treatment options for DLB and PDD are symptomatic.