APOE and depressive symptom measurement: Baseline HDRS values for depression were significantly different between APOE-2/3 and 3/4 (p < 0.05) and 2/3 vs. 4/4 (p < 0.05); and also between APOE-2/4 and 4/4 (p < 0.05) and between APOE-3/3 and 4/4 (p < 0.05) (Table 3; Figure 4).