TY - JOUR
T1 - Idea density measured in late life predicts subsequent cognitive trajectories
T2 - Implications for the measurement of cognitive reserve
AU - Tomaszewski Farias, Sarah E
AU - Chand, Vineeta
AU - Bonnici, Lisa
AU - Baynes, Kathleen
AU - Harvey, Danielle J
AU - Mungas, Dan M
AU - Simon, Christa
AU - Reed, Bruce R
PY - 2012/11
Y1 - 2012/11
N2 - Objective.The Nun Study showed that lower linguistic ability in young adulthood, measured by idea density (ID), increased the risk of dementia in late life. The present study examined whether ID measured in late life continues to predict the trajectory of cognitive change.Method.ID was measured in 81 older adults who were followed longitudinally for an average of 4.3 years. Changes in global cognition and 4 specific neuropsychological domains (episodic memory, semantic memory, spatial abilities, and executive function) were examined as outcomes. Separate random effects models tested the effect of ID on longitudinal change in outcomes, adjusted for age and education.Results.Lower ID was associated with greater subsequent decline in global cognition, semantic memory, episodic memory, and spatial abilities. When analysis was restricted to only participants without dementia at the time ID was collected, results were similar.Discussion.Linguistic ability in young adulthood, as measured by ID, has been previously proposed as an index of neurocognitive development and/or cognitive reserve. The present study provides evidence that even when ID is measured in old age, it continues to be associated with subsequent cognitive decline and as such may continue to provide a marker of cognitive reserve.
AB - Objective.The Nun Study showed that lower linguistic ability in young adulthood, measured by idea density (ID), increased the risk of dementia in late life. The present study examined whether ID measured in late life continues to predict the trajectory of cognitive change.Method.ID was measured in 81 older adults who were followed longitudinally for an average of 4.3 years. Changes in global cognition and 4 specific neuropsychological domains (episodic memory, semantic memory, spatial abilities, and executive function) were examined as outcomes. Separate random effects models tested the effect of ID on longitudinal change in outcomes, adjusted for age and education.Results.Lower ID was associated with greater subsequent decline in global cognition, semantic memory, episodic memory, and spatial abilities. When analysis was restricted to only participants without dementia at the time ID was collected, results were similar.Discussion.Linguistic ability in young adulthood, as measured by ID, has been previously proposed as an index of neurocognitive development and/or cognitive reserve. The present study provides evidence that even when ID is measured in old age, it continues to be associated with subsequent cognitive decline and as such may continue to provide a marker of cognitive reserve.
KW - Cognitive aging
KW - Cognitive reserve
KW - Idea density
KW - Linguistic ability
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U2 - 10.1093/geronb/gbr162
DO - 10.1093/geronb/gbr162
M3 - Article
C2 - 22357642
AN - SCOPUS:84867824554
VL - 67 B
SP - 677
EP - 686
JO - Journals of Gerontology - Series B Psychological Sciences and Social Sciences
JF - Journals of Gerontology - Series B Psychological Sciences and Social Sciences
SN - 1079-5014
IS - 6
ER -