MAPT and Alzheimer disease: The aim of our study is to determine the rate of beta-amyloid pathology and AD co-pathology by measuring Aβ42 and the Aβ42/Aβ40 ratio, total Tau (t-Tau) protein and p-Tau protein in the CSF in a cohort of iNPH patients, as well as to investigate the possible association between CSF biomarkers and iNPH neuropsychological profiles.