MCI in Caribbean Hispanics shows increased impairment in attention and working memory domains relative to non‐Hispanic White individuals
Katalina McInerney, Andrew Zaman, Pedro R. Mena, Larry D. Adams, Sergio J. Tejada, Jose Javier Sanchez, Katrina Celis, Kara L. Hamilton‐Nelson, Briseida E. Feliciano‐Astacio, Farid Rajabli, Gary W. Beecham, Jeffery M. Vance, Michael L. Cuccaro, Margaret A. Pericak‐Vance- Psychiatry and Mental health
- Cellular and Molecular Neuroscience
- Geriatrics and Gerontology
- Neurology (clinical)
- Developmental Neuroscience
- Health Policy
- Epidemiology
Abstract
Background
Patterns of cognitive performance associated with different stages of dementia have been primarily studied in Non‐Hispanic White (NHW) populations. This study compares patterns of cognitive performance, on a brief neuropsychological battery, in Caribbean Hispanic (CH) and NHW individuals with mild cognitive impairment, based on Clinical Dementia Rating (CDR) staging scores.
Method
Our data included 427 individuals including 299 self‐identified CH (mean age = 76.0; 69.6% female; mean education = 11.9) and 128 NHW (mean age = 72.9; 61.7% female; mean education = 13.8) who completed the CDR and a brief neuropsychological battery. Participants with other medical conditions known to impact cognition were excluded. Sex‐, age‐, and education‐adjusted Z‐scores were calculated for all cognitive tests (Logical Memory (Immediate and Delayed recall), Digit Span (Forward and Backward), and Verbal Fluency (Animals and Vegetables)). ANOVAs were used to examine the effects of ethnicity (NHW, CH) and CDR Global Score (0.5, 1.0) on the adjusted Z‐scores for all cognitive tests. CDR score distribution was adjusted through factorial ANOVA (ethnicity x CDR). Descriptive analyses included independent t‐tests to examine differences between ethnicity groups on age, sex, education, percent AD, percent Unclear, and CDR Global Score.
Result
There was a main effect of ethnicity on Digit Span Forward (p < 0.001), Digit Span Backward (p < 0.001), and Verbal Fluency – Vegetables (p < 0.01), where CH individuals showed greater impairment regardless of Global CDR score. We found a main effect of Global CDR score on all cognitive tests, where individuals with Global CDR score of 1.0 demonstrated more impairment than individuals with a Global CDR score of 0.5. No ethnicity x CDR interactions were significant.
Conclusion
Our sample of older CH and NHW individuals, presumed to have mild cognitive impairments based on CDR staging, did not differ in memory abilities. However, the CH group scored significantly lower on measures of attention and working memory. Finally, semantic fluency performance was variable and possibly influenced by cultural familiarity with different semantic categories. Among older CH individuals with mild dementia, cognitive difficulties may extend beyond memory problems and include attentional and executive function difficulties. These findings have clinical implications for diagnosis and management of CH patients.