pTau181 and tTau correlated moderately with GFAP (GFAP/pTau181: r = 0.35, p < 0.001; GFAP/tTau: r = 0.30, p < 0.005) and NfL (NfL/pTau181: r = 0.35, p < 0.001; NFL/tTau: r = 0.54, p < 0.001) within the AD group, but these correlations were lost among ONDs (GFAP/pTau181: r = 0.08; GFAP/tTau: r = 0.10; NfL/pTau181: r = 0.06; NfL/tTau: r = 0.32), likely reflecting that disease mechanisms other than amyloid and tau pathology also increase GFAP and NfL levels in these individuals. Here, NEFL is linked to Alzheimer disease.