Five-year follow-up of cognitive impairment with no dementia.
BACKGROUND
The importance of early identification of dementia has prompted numerous investigations of mild cognitive impairment and the preclinical stages of progressive degenerative disorders. To date, there is limited information from large-scale studies regarding outcomes of persons specifically identified with cognitive impairment but no dementia (CIND).


OBJECTIVE
To investigate outcomes for persons with no cognitive impairment (NCI) or CIND, focusing on its etiologic subcategories, from the Canadian Study of Health and Aging (CSHA) and to examine the predictive validity of a set of core features thought to be early manifestations of subsequent dementia.


METHODS
Five-year, longitudinal follow-up of all persons without dementia examined during the first phase of the CSHA in 1991.


METHODS
Community and institutional settings.


METHODS
Population-based sample of 883 persons with NCI and 801 persons with CIND at the first phase of the CSHA. At follow-up, 517 persons with NCI (59%) and 327 persons with CIND (41%) were alive and received clinical diagnoses.


METHODS
Mortality, institutionalization, and clinical diagnoses using the Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition criteria for dementia.


RESULTS
Persons with CIND were more likely than those with NCI to die (49% vs 30%), to be admitted to facility care (29% vs 14%), or to receive diagnoses of dementia (47% vs 15%) at follow-up. Those subsequently diagnosed as having dementia were more likely to have had impaired memory, informant-reported change in memory, and functional impairment at baseline.


CONCLUSIONS
Persons with CIND were more likely to have a negative outcome than persons with NCI during a 5-year interval. This was true across etiologic subcategories and suggests that the use of specific diagnostic criteria sets does not improve our identification of those who develop dementia compared with a broader, more inclusive approach. More factors contributed to the prediction of all forms of dementia than to AD, but the most accurate prediction was for those who remained dementia free.
Tuokko
Holly
H
Centre on Aging, University of Victoria, Victoria, British Columbia, Canada. htuokko@uvic.ca
Frerichs
Robert
R
Graham
Janice
J
Rockwood
Kenneth
K
Kristjansson
Betsy
B
Fisk
John
J
Bergman
Howard
H
Kozma
Al
A
McDowell
Ian
I
D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D002170:Canada / Q000453:epidemiology; D003072:Cognition Disorders / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology* / Q000401:mortality; D003704:Dementia / Q000209:etiology; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006304:Health Status; D006801:Humans; D007326:Institutionalization / Q000706:statistics & numerical data; D008297:Male; D008569:Memory Disorders / Q000150:complications / Q000209:etiology; D011237:Predictive Value of Tests