Intellectual faculties in patients with Alzheimer's disease regress to the level of a 4–5‐year‐old child

Abstract

Background: The present study investigated when children acquire the cognitive abilities and daily living skills that are lost in Alzheimer's disease. Methods: Among a total of 1046 students in kindergarten and elementary schools affiliated with Gunma University, Japan, five female and five male students in each grade were selected at random and examined by the mini‐mental state examination (MMSE) and physical self‐maintenance scale (PSMS). For comparison, a total of 135 outpatients with Alzheimer's disease were examined. The results of MMSE and PSMS from the first visit to Gunma University Hospital after the onset of Alzheimer's disease were used. Results: The MMSE score gradually increased from 10 points in the 1st year of kindergarten (age 3 in Japan) to 29 points in the 6th grade of elementary school (age 11 in Japan). The PSMS score increased similarly from 3 points in the 1st year of kindergarten to 6 points in the 6th grade of elementary school. The mean scores of MMSE and PSMS were 17.3 and 3.7 in the Alzheimer patients’ group. These findings suggested that cognitive and daily performance abilities examined by MMSE and PSMS are acquired in childhood during kindergarten and the early grades of elementary school. Conclusion: These cognitive and daily performance abilities of Alzheimer's disease outpatients regress to a level of a child between 4 and 5 years old. This simple understanding of Alzheimer's disease patients may contribute to further appropriate care by non‐specialists and caregivers.