Dementia with Lewy bodies.

Dementia with Lewy bodies (DLB) is the second most common diagnosis of dementia after Alzheimer disease (AD). The essential pathologic feature is the Lewy body, a neuronal inclusion containing α-synuclein, found in brainstem nuclei and the neocortex. Clinical features include early fluctuations in attention, hallucinations, and parkinsonism, with progression to a combined cortical and subcortical dementia. To distinguish it from Parkinson disease dementia, a time course of one year from cognitive changes to motor feature onset has been established. There is more severe impairment of verbal fluency, executive function, and visuospatial abilities in DLB patients. Both rapid eye movement sleep behavior disorder and neuroleptic sensitivity are notable in this patient group. Treatment is aimed at symptom management. Cholinesterase inhibitors can be beneficial for behavioral and cognitive issues, whereas dopaminergic agents may help motor symptoms. Survival is equivalent to AD when measured from symptom onset, though diagnosis in DLB may be delayed.