INTRODUCTION: The associations between subjective cognitive decline (SCD), cognition, and amyloid were explored across diverse participants in the A4 study.

METHODS: Five thousand one hundred and fifty-one non-Hispanic White, 262 non-Hispanic Black, 179 Hispanic-White, and 225 Asian participants completed the Preclinical Alzheimer Cognitive Composite (PACC), self- and study partner-reported Cognitive Function Index (CFI). A subsample underwent amyloid positron emission tomography ( F-florbetapir) (N = 4384). We examined self-reported CFI, PACC, amyloid, and study partner-reported CFI by ethnoracial group.

RESULTS: The associations between PACC-CFI and amyloid-CFI were moderated by race. The relationships were weaker or non-significant in non-Hispanic Black and Hispanic White groups. Depression and anxiety scores were stronger predictors of CFI in these groups. Despite group differences in the types of study partners, self- and study partner-CFI were congruent across groups.

DISCUSSION: SCD may not uniformly relate to cognition or AD biomarkers in different ethnoracial groups. Nonetheless, self- and study partner-SCD were congruent despite differences in study partner type. Highlights Association between SCD and objective cognition was moderated by ethnoracial group. Association between SCD and amyloid was moderated by ethnoracial group. Depression and anxiety were stronger predictors of SCD in Black and Hispanic groups. Study-partner and self-reported SCD are congruent across groups. Study-partner report was consistent despite difference in study partner types.