Using the Everyday Cognition Scales (ECog), depression, and vascular risk to predict conversion to cognitive impairment in different ethnoracial groups

Abstract

AbstractBackgroundOur previous work found that greater subjective cognitive concerns (SCC) at baseline was associated with increased risk of developing mild cognitive impairment (MCI) or dementia in Caucasians and African Americans, but not Hispanics. The present study examined whether medical co‐morbidities or depression may account for some of these differences.MethodsParticipants included 205 Caucasians, 101 African Americans, and 95 Hispanics, all cognitively normal at baseline, who are part of the University of California, Davis Alzheimer’s Disease Center longitudinal cohort. SCC was measured using the self‐reported Everyday Cognition Scales (ECog) Memory domain. Over an average of 4.7 years, 116 developed MCI or dementia. Associations with incident cognitive impairment were assessed using Cox proportional hazards models, adjusting for age and education. Models considered the interaction between race/ethnicity and the ECog score, as well as either depression (Geriatric Depression Scale) or vascular risk (proportion present out of hypercholesterolemia, diabetes, hypertension). Models were then run separately in each racial/ethnic group.ResultsIn models that included depression and vascular risk separately, there was a significant interaction (p<0.05) between racial/ethnic group and SCC, consistent with our earlier findings. GDS was not associated with progression for any racial/ethnic group (p>0.1), SCC was associated with progression in African Americans (HR=2.05, 95% CI=1.20, 3.50; p=0.009), but not Caucasians (p=0.08) or Hispanics (p=0.34). In contrast, vascular risk was marginally associated with progression in Hispanics (HR=3.4, 95% CI=0.98, 11.72; p=0.054), but not Caucasians (p=0.8) or African Americans (p=0.4). When accounting for vascular risk, SCC was associated with progression in Caucasians (HR=1.7, 95% CI=1.1, 2.6; p=0.01) and African Americans (HR=2.04, 95% CI=1.27, 3.26; p=0.003), but not Hispanics (p=0.4).ConclusionsResults suggest there are differences in the degree to which SCCs and vascular risk are associated with developing cognitive impairment across different ethnoracial groups. SCC was generally associated with incident impairment in Caucasians and African Americans, but not Hispanics. Medical co‐morbidities were more associated with incident impairment in Hispanics compared to Caucasians.