Similar reasoning can be applied on our found negative correlation between total plasma IAPP levels and CSF Aβ levels in AD patients, suggesting that increased amount of aggregation-prone IAPP deriving from the periphery could seed Aβ and thereby contribute to the accumulation of Aβ in the brain [12] (which lowered levels of Aβ levels in CSF are indicative of). Here, IAPP is linked to Alzheimer disease.