Key points for early clinical diagnosis of dementia with Lewy bodies

Abstract

I have presented several key points to diagnose dementia with Lewy bodies （DLB） in the early stage.　DLB shows relatively preserved memory, but disproportional impairment of visuospatial and executive functions compared to Alzheimer’s disease （AD）.　Including tests such as drawing figures and trail-making tests may be helpful in screening for DLB.　Impaired imitation of finger configurations are more frequent in DLB than in other dementias such as AD, so that finding also supports a diagnosis of DLB.　Compared to early AD, early DLB frequently shows several characteristic symptoms, including REM sleep behavior disorder （RBD）, day-time somnolence, fluctuation, easy falls, visual hallucinations, illusions, misidentifications, anxiety, depression, hyposmia, and constipation.　In particular, RBD and depression can precede other clinical symptoms of DLB by several years.　DLB shows more errors than AD in the pareidolia test, and this may be useful for early diagnosis of DLB.　Although each symptom may be nonspecific for DLB, combinations of these early symptoms offer clues to suspicion of early DLB.　Detections of these early signs and symptoms, with use of essential neuroimaging, will facilitate early diagnosis of DLB.