By adding NfL to the panel (age+sex+APOE4+NfL panel), the discrimination between HC vs. AD reached a significantly higher AUC of 84.5% (95%CI = 0.76–0.93, Figure 3A) compared to the age+sex+APOE4 panel alone (p = 0.003), while the other calculations failed to achieve significantly better results (HC vs. MCI AUC 68.8%, 95%CI = 0.58–0.80, MCI vs. AD AUC 72%, 95%CI = 0.63–0.82), amyloid positivity (AUC 76.5%, 95%CI = 0.61–0.87, Figures 3B–D). Here, APOE is linked to Alzheimer disease.