Niigata University Jun 30 2026 Reviewed Researchers at Niigata University have conducted the first comprehensive reappraisal in nearly 30 years of the risk of Alzheimer's disease (AD) associated with APOE-e4 homozygosity ( e4*4 ) in the Japanese population. Their findings suggest that the risk, while still substantial, is lower than estimates that have been widely cited since the 1990s. AD is the most common cause of dementia worldwide. Among the many factors that influence disease risk, the