MAPT and Alzheimer disease: Among the individuals who underwent amyloid PET (n = 50) or CSF Aβ (n = 1149) analysis, CSF p-tau (n = 1149) and FDG PET (n = 988) at baseline, a total of 72 participants had normal AD biomarkers (A-T-N-) including those followed-up for a year or more.