MAPT and Alzheimer disease: Analysis of CSF biomarkers at inclusion showed, as expected, higher CSF total tau (tau) and phospho‐tau (p‐tau181) levels and lower amyloid Aβ42 levels, Aβ42/Aβ40, and Aβ42/p‐tau181 ratios in AD patients compared to naMCI and aMCI individuals.