2006 Fiscal Year Final Research Report Summary

The study about the conversion rate from Mild Cognitive Impairment to Alzheimer's type dementia

Research Project

Project/Area Number	17591229
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	Psychiatric science
Research Institution	Wakayama Medical University
Principal Investigator	SHIBA Mitsuru Wakayama Medical University, School of Health and Nursing Science, Professor, 保健看護学部, 教授 (50178894)
Co-Investigator(Kenkyū-buntansha)	YAMAMOTO Akihiro Wakayama Medical University, School of Health and Nursing Science, Associate Professor, 保健看護学部, 講師 (20320054)
Project Period (FY)	2005 – 2006
Keywords	Dementia / Epidemiology / Mild Cognitive Impairment / Alzheimer's type dementia / 疫学 / 脳神経疾患
Research Abstract	Recently, patients who are at high risk for developing Alzheimer's disease (AD) have become a focus of study. The term mild cognitive impairment (MCI) is popular and a major issue of concern. However, there has been controversy regarding the precise definition of the concept and its implementation in various clinical settings. The purpose of this study is to develop the new screening method in using the recall item of Hasegewa's Dementia Scale-Revised, because this scale is widely used to screen for dementia in Japan. We proposed MIND (Memory Impairment No Dementia) criteria which met cognitive impairment without dementia (HDS-R total scores are 24 or over, and the recall item scores are 3 or below), to designate an early but abnormal status of cognitive impairment. We examined 490 residents 65years and older in H-cho in 1998. When we adopted MIND criteria for them, 85(17.3 %) subjects met the criteria. Fifty seven subjects of them took part in the investigation in 2005. Eight (14.0%) subjects evolved to dementia and 6 (7.1%) of them met the criteria of Alzheimer's type dementia. In scores of recall item (0, 1, 2, 3), the conversion rate (%) from MIND to AD was 50% for 0, 66.7% for 1, 7.7% for 2 and 0% for 3, respectively. The result suggests that low scores in recall item of HDS-R appear valid as predictor variables.