Cognitive predictors of mortality in elderly retirees: results from the Freedom House study.
OBJECTIVE
The objective of this longitudinal cohort study was to study the cognitive domains associated with five-year longitudinal survival among healthy, well-educated, noninstitutionalized elderly.


METHODS
Survival curves were generated as a function of cross-sectional baseline cognitive test performance.


RESULTS
Nonverbal tests were significantly associated with survival. This finding was markedly consistent. Several nonverbal tasks were each significantly associated with survival independently of age, gender, baseline level of care, and healthcare utilization. In a multivariate model, copying a clock made the strongest, independent contribution to survival.


CONCLUSIONS
Right hemisphere integrity in general and nonverbal drawing tasks in particular have been associated with survival in conditions as diverse as Alzheimer disease, stroke, and epilepsy. This study extends this association to "normal" aging. The mechanism by which nonverbal cognitive function is related to mortality remains unclear but may be mediated by changes in right hemisphere cortical control of autonomic function. Nondemented older persons may be at risk. Clock drawing may provide a simple means of identifying them.
Royall
Donald R
DR
Department of Psychiatry, South Texas Veterans' Health System Audie L. Murphy Division GRECC and the University of Texas Health Science Center, San Antonio, TX 78284-7792, USA. royall@uthscsa.edu
Chiodo
Laura K
LK
Mouton
Charles
C
Polk
Marsha J
MJ
D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000523:psychology*; D000704:Analysis of Variance; D003071:Cognition; D003072:Cognition Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D015577:Geriatric Assessment / Q000379:methods*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D011237:Predictive Value of Tests; D011594:Psychometrics / Q000379:methods; D012179:Retirement / Q000523:psychology*; D016019:Survival Analysis; D013647:Task Performance and Analysis; D013781:Texas / Q000453:epidemiology; D013995:Time