APOE and Alzheimer disease: A multiplex biochemical biomarker study of 146 known plasma analytes from the Alzheimer's Disease Neuroimaging Initiative (ADNI) found several analytes that were highly associated with depressive symptoms, including hepatocyte growth factor, insulin polypeptides, pregnancy-associated plasma protein-A, and vascular endothelial growth factor.139 Medications, body mass index, APOE alleles, serum glucose, and CSF Aβ levels were also assessed and did not significantly affect the associations between these plasma marker levels and depressive symptom scores.