Study of the relationship between oral function and cognitive decline in elderly people

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K17390
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Social dentistry
• Research Institution: Kyushu University (2018-2019); Fukuoka Dental College (2017)
• Principal Investigator: Mizutani Shinsuke 九州大学, 歯学研究院, 准教授 (90643312)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 口腔機能 / 高齢者 / 軽度認知機能障害 / 認知症

Outline of Final Research Achievements

Mild cognitive impairment (MCI) is known as the preliminary phase of dementia. Patients with this condition are at a risk of developing dementia; however, they might also revert to normal. The aim of this study was to examine whether the management of oral functions in the dental clinic can prevent cognitive decline in the elderly.
The total number of participants in this study was 52, and data was collected from 35 participants after 2 years. They got a dental check-up regularly and received dental treatment as needed. For the assessment of cognitive decline, the MoCA-J, MMSE and MCI biomarker levels in the blood were used. Oral function was evaluated by tongue pressure and masticatory performance.
One out of 23 participants had MCI, and 8 out of 12 MCI participants reverted to normal conditions. Improvement in tongue pressure was associated with the MMSE score. Furthermore, improvement in the masticatory performance was associated with the MMSE score and MCI biomarker levels.

Free Research Field

高齢者歯科学

Academic Significance and Societal Importance of the Research Achievements

我が国では急速な高齢化により、認知症患者の増加が問題となっている。現在、認知症を治す絶対的な方法は確立されていないため、発症を予防することが重要である。本研究では、認知症の前段階であるとされる軽度認知障害および認知機能に問題のない高齢者を対象に2年間における口腔機能と認知機能の変化を調査した。
定期的に口腔管理を行った35名の患者において、2年間における舌圧の低下および咀嚼機能の低下は、認知機能低下と関連した。口腔機能を維持、向上させることで、認知機能の低下を予防できる可能性が示唆された。