[Development of a novel one-phrase screening test for early Alzheimer disease].

Aim: "Saving appearances behavior", pretending to know the correct answer, or a reply of deceptive replies, are often found in the reply of patients with dementia. We have already found that we can classify the answers to "what is the latest news on TV or newspapers?" into 4 types, including saving appearances answer. The purpose of the present study is to develop a simple clinical diagnostic method based on the answers to "what is the latest news on TV or newspapers?" for differentiating patients with Alzheimer's disease (AD) from those with mild cognitive impairment (MCI), and to test the validity, sensitivity and specificity of the method.

Methods: We recruited 133 consecutive outpatients with AD, 116 with MCI, and 54 normal cognitive aging controls (NC). Mini-Mental State Examination (MMSE) was performed for all of the subjects. Severity of memory disturbance was rated 0 (none) to 3 (severe) according to the results of the 3-object recall portion of the MMSE questionnaire.

Results: Only 20% of AD and 32% of MCI responded correctly about the recent news while 96% of NC responded correctly. Among patients with AD and MCI, one third of them showed "saving appearance behavior". Taking the result of the memory disturbance according to the MMSE in consideration, the present study indicates that the AD patients can be distinguished from MCI and NC with high sensitivity (98%) and high specificity (94%) using this simple, one-phrase question.

Conclusions: "What is the latest news on TV or papers?" was highly effective in identifying AD and MCI. The present study suggests that the "saving appearances answer" is associated with the onset or awareness of memory impairment, the maintenance of the frontal lobe function and other characteristics of the patient.