Notably, the study that reported associations with all core AD biomarkers (p-tau/Aβ42, t-tau/Aβ42 and Aβ42) did not adjust for cognitive status or cognitive scores, and the sample included only 11% with MCI.23 Other studies have found no relationship between apathy and core AD CSF biomarkers across the cognitive clinical spectrum.27-29. This evidence concerns the gene MAPT and Alzheimer disease.