MAPT and dementia: Our findings are in line with previous studies, showing an effect of ApoE4 on CSF Aβ42 and CSF tau in cognitively unimpaired subjects and early MCI, but not in AD dementia, supporting the idea that other mechanisms of neurodegeneration may override the effect of ApoE4 later in the course of AD (Herukka et al. 2007; Risacher et al. 2013; Mofrad et al. 2020).