APOE and Alzheimer disease: Furthermore, we aimed to assess potential associations between plasma apoE levels, global cognition, AD CSF biomarkers (amyloid-β40 (Aβ40), amyloid-β42 (Aβ42), total tau (t-tau), and phosphorylated tau at threonine (Thr) 181 (p-tau181)) as well as CSF levels of neurofilament light (NfL) chain, soluble TREM2 (sTREM2), and plasma lipids.