APOE and Mental deterioration: APOE4 carriers (versus non-carriers) have worse long term cognitive trajectories in the 5 years following surgery,8 and APOE4 carriers who underwent surgery had worse long term cognitive decline than non-APOE4 carriers who underwent surgery, and as compared to both APOE4 carriers and non-APOE4 carriers who did not undergo surgery.9APOE4 carriers have altered CSF levels of inflammation-related proteins such as C-reactive protein (CRP), complement and YKL-40/CH3L1,10, 11 which may contribute to long term neurocognitive decline.