In the APOE ε4− AD group, the level of plasma HDL significantly and positively predicted CSF p‐tau 181 level (β = 26.95, B/H adjusted p = 0.049), and the levels of plasma TG significantly and negatively predicted CSF p‐tau 181 level (β = −9.68, B/H adjusted p = 0.026) (Figure 5D,E). Here, APOE is linked to Alzheimer disease.