1 Research Team for Promoting Independence and Mental Health, Tokyo Metropolitan Institute of Gerontology and Geriatrics, Tokyo, Japan.
2 Department of Frailty Research, Center for Gerontology and Social Science, Research Institute, National Center for Geriatrics and Gerontology, Aichi, Japan.
3 Division of Preventive Dentistry, Department of Oral Health Science, Hokkaido University, Sapporo, Japan.
4 Integrated Research Initiative for Living Well with Dementia, Tokyo Metropolitan Institute of Gerontology and Geriatrics, Tokyo, Japan.