1. Department of Cardiovascular Medicine, Nephrology and Neurology, University of the Ryukyus Graduate School of Medicine, Nishihara-cho, Okinawa, Japan
2. Center for Comprehensive Care and Research on Memory Disorders, Hospital, National Center for Geriatrics and Gerontology, Obu, Aichi, Japan
3. School of Medical Technology, Kurume University, Kurume, Fukuoka, Japan
4. Biostatistics Center, Graduate School of Medicine, Kurume University, Kurume, Fukuoka, Japan
5. Department of Prevention and Care Science, Research Institute, National Center for Geriatrics and Gerontology, Obu, Aichi, Japan
6. Department of Cognition and Behavioral Science, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya, Aichi, Japan