MAPT and Cognitive impairment: From 250 subjects with suspected AD-related cognitive impairment, we enrolled 163 patients with decreased CSF levels of Aβ42 and normal CSF p-tau (A + T −  = 98) or pathological CSF p-tau (A + T +  = 65), as well as 36 sex-/age-matched healthy controls (A − T −) (see Additional file 1).