IAPP and Alzheimer disease: Among the 3 plasma amylin concentration groups, compared with the low plasma amylin concentration group, the high plasma amylin concentration group had lower risks of dementia (6.7% vs 4.5%) and AD (5.6% vs 2.3%), but the extremely high plasma amylin concentration group had higher risks of dementia (17.2%) and AD (14.3%) (Table 2).