Ethnic differences in the prevalence of amyloid positivity and cognitive trajectories

INTRODUCTION: We investigated the prevalence of amyloid beta (A beta) positivity (+) and cognitive trajectories in Koreans and non-Hispanic Whites (NHWs). METHODS: We included 5121 Koreans from multiple centers across South Korea and 929 NHWs from the Alzheimer's Disease Neuroimaging Initiative (ADNI). Participants underwent A beta positron emission tomography and were categorized into cognitively unimpaired (CU), mild cognitive impairment (MCI), and dementia stages. Age, sex, education, and apolipoprotein E. genotype were adjusted using multivariable logistic regression and stabilized inverse probability of treatment weights based on the propensity scores to mitigate imbalances in these variables. RESULTS: The prevalence of A beta+ was lower in CU Koreans than in CU NHWs (adjusted odds ratio 0.60). A beta+ Koreans showed a faster cognitive decline than A beta+ NHWs in the CU (B = -0.314, p = .004) and MCI stages (B = -0.385, p < .001). DISCUSSION: Ethnic characteristics of A beta biomarkers should be considered in research and clinical application of A beta-targeted therapies in diverse populations.