Differences in amyloid PET positivity based on ethnoracial group and social determinants of health: The new IDEAS study

INTRODUCTION: This study leverages a large, diverse cohort to characterize ethnoracial differences in amyloid positron emission tomography (PET) positivity and identify social determinants of health (SDOHs) contributing to these differences. METHODS: We assessed differences in amyloid PET positivity by ethnoracial group (Black, Latinx, or all other races/ethnicities [AORE]) among Medicare beneficiaries with cognitive impairment. Secondary analyses associated various SDOHs with amyloid PET positivity. RESULTS: Among 5757 participants (21.7% Black, 20.3% Latinx, 58.1% AORE), we found lower odds of amyloid positivity in Black (odds ratio [OR]: 0.72, 95% confidence interval [CI]: 0.62-0.83) and Latinx (OR: 0.78, 95% CI: 0.67-0.91) compared to AORE. Individuals in the comfortable (OR: 1.22, 95% CI: 1.05-1.42) and distressed (OR: 1.40, 95% CI: 1.08-1.82) Area Deprivation Index (ADI) groups had greater odds of amyloid positivity than individuals in the prosperous group. DISCUSSION: Amyloid PET positivity rates were lower among Black and Latinx individuals and higher among individuals in more deprived ADI categories. This has potential implications for anti-amyloid therapies.