A longitudinal study of cognitive trajectories in Mexican Americans age 75 and older.
OBJECTIVE
To identify distinct trajectories for global cognition, memory, and non-memory domains among Mexican American adults 75 years of age and older.


METHODS
The final sample included 1336 participants of the Hispanic Established Population for the Epidemiologic Study of the Elderly observed during four Waves from 2004-2005 to 2012-2013. Latent class growth curve models were used to identify distinct trajectories for global cognition, memory, and non-memory.


RESULTS
Three trajectory classes were identified for global cognition, memory, and non-memory domains. Nearly 31% of the final sample maintained high global cognition (persistent high), 52.6% experienced slight decline (decline but high), and 15% experienced severe decline in global cognition (decline to low). Over 95% of participants classified in the decline to low trajectory for global cognition were also classified as decline to low for memory and non-memory. This high level of consistency for memory and non-memory domains was observed for the decline but high (97.0%) and persistent high (93.7%) trajectory classes.


CONCLUSIONS
These results indicate that the majority of Mexican American older adults will experience varying degrees of cognitive decline. However, a substantial proportion of older Mexican Americans are able to maintain high cognitive functioning into advanced age despite the high prevalence of risk factors for cognitive decline in this population. Copyright © 2016 John Wiley & Sons, Ltd.
Division of Rehabilitation Sciences, University of Texas Medical Branch, Galveston, Texas, USA.
Brian
B
Downer
Preventive Medicine and Community Health, University of Texas Medical Branch, Galveston, Texas, USA.
Nai-Wei
NW
Chen
Division of Geriatric Medicine, University of Texas Medical Branch, Galveston, Texas, USA.
Mukaila
M
Raji
Preventive Medicine and Community Health, University of Texas Medical Branch, Galveston, Texas, USA.
Kyriakos S
KS
Markides
D000368:Aged; D000369:Aged, 80 and over; D003071:Cognition; D003072:Cognition Disorders / Q000453:epidemiology* / Q000523:psychology; D060825:Cognitive Dysfunction / Q000453:epidemiology; D003704:Dementia / Q000523:psychology; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D017058:Mexican Americans / Q000523:psychology* / Q000706:statistics & numerical data; D010300:Parkinson Disease / Q000523:psychology; D015995:Prevalence; D012307:Risk Factors; D014481:United States / Q000453:epidemiology
Mexican Americans; cognitive decline; minority aging