APOE and dementia: Analyses also examined whether dementia status, age, sex, education, <i>APOE ε</i>4 carrier status, medical comorbidities, or fasting status modified potential racial differences.<h4>Results</h4>Of the 324 Black and 1,547 White participants, there were 158 Black and 759 White participants with plasma Aβ measures from at least two longitudinal samples over a mean interval of 6.62 years.