APOE and Alzheimer disease: Additionally, when we stratified the AD sample by APOE ε4 carrier status, Ng levels were significantly higher in aMCI due to AD APOE ε4 carriers compared to non-carriers (F[1, 109] = 8.22, p = .005, η2 = 0.07, AUC = 0.65, 95% CI: 0.57–0.78, with a sensitivity of 0.59 and specificity of 0.69) but not in AD dementia APOE ε4 carriers compared to non-carriers (F [1, 67] = 2.20, p = .144, η2 = 0.03, AUC = 0.60, 95% CI: 0.49–0.79, with a sensitivity of 0.58 and specificity of 0.33).