To further explore the translational science, plasma levels of a biomarker for the presence of AD co-pathology (tau phosphorylated at position 181, ptau181)56 were measured in baseline samples and the results evaluated by the presence or absence of AD co-pathology (i.e., plasma ptau181 < or ≥ 2.2 pg/mL). Here, MAPT is linked to Alzheimer disease.