MAPT and Alzheimer disease: Before accounting for demographic characteristics, educational level, family history of AD, BMI, and cognitive scores, the MCI cutoff for Aβ1-42 level was higher (208 [95% CI, 126-321] vs 197 [95% CI, 183-245] pg/mL), and the cutoffs for tau level (51 [95% CI, 31-59] vs 59 [95% CI, 56-92] pg/mL), pTau181 level (12 [95% CI, 12-19] vs 20 [95% CI, 12-27] pg/mL), and tau to Aβ1-42 ratio (0.17 [95% CI, 0.13-0.46] vs 0.23 [95% CI, 0.22-0.33]) were lower in African American compared with white participants.