[1] Natl Cerebral & Cardiovasc Ctr, Dept Neurol, 6-1 Kishibe Shimmachi, Suita, Osaka 5648565, Japan
[2] Natl Cerebral & Cardiovasc Ctr, Dept Prevent Med & Epidemiol, Osaka, Japan
[3] Univ Turku, Turku PET Ctr, Turku, Finland
[4] Turku Univ Hosp, Turku, Finland