The association of depression and apathy with Alzheimer’s disease biomarkers in a cross-cultural sample

Abstract

Cross-cultural differences in the association between neuropsychiatric symptoms and Alzheimer's disease (AD) biomarkers are not well understood. This study aimed to (1) compare depressive symptoms and frequency of reported apathy across diagnostic groups of participants with normal cognition (CN), mild cognitive impairment (MCI), and dementia, as well as ethnic groups of Hispanic Americans (HA) and European Americans (EA); (2) evaluate the relationship between depression and apathy with Aβ deposition and brain atrophy. Statistical analyses included ANCOVAs, chi-squared, nonparametric tests, correlations, and logistic regressions. Higher scores on the Geriatric Depression Scale (GDS-15) were reported in the MCI and dementia cohorts, while older age corresponded with lower GDS-15 scores. The frequency of apathy differed across diagnoses within each ethnicity, but not when comparing ethnic groups. Reduced volume in the rostral anterior cingulate cortex (ACC) significantly correlated with and predicted apathy for the total sample after applying false discovery rate corrections (FDR), controlling for covariates. The EA group separately demonstrated a significant negative relationship between apathy and superior frontal volume, while for HA, there was a relationship between rostral ACC volume and apathy. Apathy corresponded with higher Aβ levels for the total sample and for the CN and HA groups.

Keywords:

• Aging
• apathy
• mild cognitive impairment

Disclosure statement

None of the authors have conflict of interest involving this manuscript.

Additional information

Funding

This research was supported by the Florida Department of Health grants numbers 9AZ01 and 21A01 Florida Atlantic University, the National Institute of Aging Grants number 5 P50 AG047726602 1Florida Alzheimer’s Disease Research Center, University of Miami and R01 AG047649-01A1 and 1P30AG066506-01, Florida International University and the National Science Foundation grants number CNS-1920182 and CNS1532061 Florida International University.