Clinical diagnosis of dementia with Lewy bodies in a Japanese dementia registry.

We found 15 patients with dementia with Lewy bodies (DLB) and 232 patients with Alzheimer's disease (AD) among 327 consecutive patients with mild to moderate dementia in a Japanese dementia registry, using the clinical criteria of the Consortium on DLB International Workshop. The percentage of females was significantly lower in DLB than in AD (p < 0.01), while age at examination, Mini-Mental State Examination score and duration of cognitive symptoms were comparable between the two diseases. Eight of the 15 DLB patients (53%) had spontaneous parkinsonism, which was observed in 6 of the 232 AD patients (2.6%). Visual hallucinations were reported by 11 of the 15 DLB patients (73%) and 8 of the 232 AD patients (3.4%). Cognitive fluctuation was positive in 13 of the 15 DLB patients (87%). We found two types of episodic cognitive deterioration: one was characterized by pronounced disturbances of attention and alertness (inattention type), and the other was characterized by marked and bizarre disturbances of orientation in time and places, and misidentification of persons (disorientation type). Systematized delusion was observed in 8 DLB patients, and 5 patients showed neuroleptic sensitivity. Patients with DLB have a unique dementia syndrome even in the stage of mild to moderate cognitive impairments. Further studies are recommended to establish diagnosis, treatment and management.