APOE and Alzheimer disease: To further study the possible role of co-pathology, the authors divided their sample of 495 neuropathologically confirmed DLB into three groups, based on the extent of AD co-pathology, as no AD co-pathology (pure DLB; n = 88), intermediate (n = 66) and high (n = 341) AD co-pathology, and they tested the association of the APOE ε4 against the control group.