APOE and Brain atrophy: Our main findings could be summarized as follows: (1) prolonged ventricular repolarization was independently associated with MCI, and aMCI in particular, but not with naMCI; (2) prolonged ventricular repolarization was independently associated with cortical atrophy and increased total WMH, and PWMH in particular, but not with DWMH; and (3) the associations of prolonged ventricular repolarization with atrophic brain measures varied by CHD and APOE gene, such that QT and JT intervals were associated with brain atrophy only among people with CHD or APOE ε4 non-carriers.