Sample size estimates were calculated to detect 25% and 50% treatment effects with 80% power in those with cognitive impairment.<h4>Results</h4>Among 415 participants (mean [SD] age, 72.3 [7.6] years; 220 women [53%]; 69 SAA positive [17%] and 346 SAA negative [83%]), there was a significant interaction between SAA status, sex, and time on tau accumulation (β, 0.061; 95% CI, 0.030-0.093; P < .001). Here, MAPT is linked to Cognitive impairment.