Study populations
The Hisayama Study is a population-based prospective longitudinal study of cerebrovascular diseases and dementia in the town of Hisayama, a suburban community adjacent to the city of Fukuoka in Japan15,16. Since 1961, we have performed surveys of the neurological and physical condition of residents every 1 to 2 years. Comprehensive surveys of dementia have also been carried out every 5 to 7 years since 1985 in the older residents. In 2007–2008, a total of 1581 residents aged ≥ 65 years (participation rate = 88.6%) underwent a screening survey. After the exclusion of 3 residents who refused to participate in this survey, 161 with prevalent dementia, and 46 without available data of serum SAM and SAH, the remaining 1371 residents (596 men and 775 women) were enrolled in the present study. This study was approved by the Kyushu University Institutional…
