2020 年度実施状況報告書

Does Japanese diet prevent brain atrophy in cognitively normal individuals: a 10-years cohort study of middle-aged and elderly dwelling Japanese.

研究課題

研究課題/領域番号	20K22175
研究機関	国立研究開発法人国立長寿医療研究センター
研究代表者	張シュ国立研究開発法人国立長寿医療研究センター, 老年学・社会科学研究センター, 研究員 (00874471)
研究期間 (年度)	2020-09-11 – 2022-03-31
キーワード	Green tea / Gray matter / White matter / Hippocampus / Atrophy / Cohort
研究実績の概要	The present study uses the 3-day dietary record(3DR) data and the 3D brain magnetic resonance imaging (MRI) images during a 10-year follow-up to elucidate (1) whether Japanese diet suppresses the total brain atrophy in cognitively normal individuals, and (2) which part(s) of the brain is affected. The main task this year is to implement a 10-year follow-up survey to collect the 10-year MRI images. The study conducted this year was based on existing 3DR data and 2-year MRI images. Among the middle-aged and older subjects who participated in the 6th and 7th survey of the National Institute for Longevity Sciences-Longitudinal Study of Aging project, 1691 whose data on both the 3DR and the MRI images were available were included in the analyses. First, we examined the relationship between green tea consumption, which has been widely reported to be beneficial for cognitive function, and annual brain atrophy. Green tea consumption (mL/day) data were collected with a 3DR. Annual changes in gray matter, white matter, and hippocampal volume (mL/y) estimated by T1-weighted brain MRI and FreeSurfer software. In the multivariable-adjusted general linear model, green tea consumption was negatively associated with annual hippocampal volume change. On the other hand, no associations were observed for gray matter or white matter volume annual changes.
現在までの達成度 (区分)	現在までの達成度 (区分) 2: おおむね順調に進展している理由 Based on the existing dietary assessment data and 2-years MRI images, I was able to secure a certain number of subjects and examine important food items of Japanese diet and brain atrophy / area-specific brain atrophy. The findings obtained will be submitted to international academic journals.
今後の研究の推進方策	Based on the 10-year follow-up data collection, I will further investigate the relationship between Japanese diet and its specific food items and long-term age-related changes in the brain.
次年度使用額が生じた理由	Due to the coronavirus disease (COVID-19) epidemic, the 3D brain MRI image collection was slightly delayed from the original plan, and the research funding for implementation has also been reduced. Since the brain image collection planned for the next fiscal year is very expensive, the surplus will be included in the budget.