Validation of Addenbrooke's cognitive examination for detecting early dementia in a Japanese population.

There is a clear need for brief, but sensitive and specific, cognitive screening instruments for dementia. We assessed the diagnostic accuracy of the Japanese version of Addenbrooke's Cognitive Examination (ACE) in identifying early dementia in comparison with the conventional Mini-Mental State Examination (MMSE). Standard tests for evaluating dementia screening tests were applied. A total of 201 subjects (Alzheimer's disease (AD)=65, frontotemporal dementia (FTD)=24, vascular dementia=26, dementia with Lewy bodies=11, mild cognitive impairment (MCI)=13, and controls=62) participated in this study. The reliability of the ACE was very good (alpha coefficient=0.82). In our patient series, the sensitivity for diagnosing dementia with an ACE score of ≤74 was 0.889 with a specificity of 0.987, and the sensitivity of an ACE score of ≤80 was 0.984 with a specificity of 0.867. The Japanese version of the ACE is a very accurate instrument for the detection of early dementia, and should be widely used in clinical practice.