Ethnic Differences in the Association Between Cognitive Performance and Informant-rated Cognitive Decline.

Objectives: It is unknown whether cognitive test scores are equivalently associated with informant-rated cognitive decline across culturally and linguistically diverse older adults. We examined the association between cognitive domain scores on the Harmonized Cognitive Assessment Protocol (HCAP) and informant-rated cognitive decline in a harmonized population-based sample of older adults.

Design, setting, and participants: We combined data from the HCAP sub-study of the Health and Retirement Study (HRS; 2016) and the Brain Attack Surveillance in Corpus Christi-Cognitive (BASIC-C; 2018-2020) study. We included Hispanic/Latino-a-e-x (H/L; n = 566) and non-H/L white (NHW; n = 2,145) older adults.

Measurement: Both studies included the HCAP cognitive assessment with domain scores for memory, attention/executive function (EF), language, visuospatial, orientation, and general cognitive performance (GCP). Informants rated cognitive decline with the Informant Questionnaire of Cognitive Decline in the Elderly (IQCODE).

Results: Cognitive domain scores were more strongly associated with IQCODE scores for NHW than H/L participants for four of six domains (GCP, EF, visuospatial, and orientation) after adjusting for demographics (age, sex/gender, education) and study membership. Informants generally rated greater cognitive decline in NHW than H/L respondents for a given cognitive domain score, and the magnitude of this difference was greater for lower cognitive test scores.

Conclusions: We found generally weaker associations between cognitive performance and informant-rated cognitive decline in H/L compared to NHW older adults. These findings suggest cognitive measurement differences across culturally and linguistically diverse older adult populations, which may result in underestimation of cognitive impairment in H/L populations.