Association between dietary factors and cognitive impairment in Japanese population(Fostering Joint International Research)

2019 Fiscal Year Final Research Report

• Project/Area Number: 15KK0342
• Research Category: Fund for the Promotion of Joint International Research (Fostering Joint International Research)
• Allocation Type: Multi-year Fund
• Research Field: Epidemiology and preventive medicine
• Research Institution: Shiga University of Medical Science
• Principal Investigator: Miyagawa Naoko 滋賀医科大学, 医学部, 客員助教 (20388169)
• Project Period (FY): 2016 – 2019
• Keywords: 認知機能 / 日系アメリカ人 / 生活習慣 / 日米比較

Outline of Final Research Achievements

This study aimed to identify related factors for low cognitive function in two groups of genetically similar Japanese men exposed to Westernized lifestyles from different starting points in life using cross-sectional data from Japanese-American based in Hawaii and the Japanese based in Japan. Cognitive function was evaluated by participants’ performance on the Cognitive Abilities Screening Instrument (CASI), a validated comprehensive measure of global cognitive function developed for use in cross-cultural and cross-national studies. Older Hawaii-based men were more likely to achieve a low CASI score than were older Japan-based men. In the present study, lower cognitive function among older Japanese men was mostly explained by the differences in educational attainment between the cohorts.

Free Research Field

栄養疫学

Academic Significance and Societal Importance of the Research Achievements

日本からハワイに移住した日系アメリカ人は若年期から欧米の生活習慣を経験しており、近未来の日本人の疾病状況を予測でき得る集団である。これまで、日系アメリカ人の認知症有病率は日本在住の日本人よりも高いことが報告されていたが、本研究の結果により教育歴の差で説明できる可能性が示唆された。また、欧米風の生活習慣に異なる期間曝露したハワイの日系アメリカ人と日本在住日本人高齢男性において、低い認知機能スコアに関連する循環器疾患の既往と心血管代謝障害因子は異なったため、認知機能低下予防に向けて不健康な生活習慣や心血管代謝障害の曝露期間も考慮する必要がある。