Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-25T05:39:20.432Z Has data issue: false hasContentIssue false

Normal Aging and Executive Functions in “Old-Old” Community Dwellers: Poor Performance Is Not an Inevitable Outcome

Published online by Cambridge University Press:  10 January 2005

Olivier Piguet
Affiliation:
Centre for Education & Research on Ageing at Concord Repatriation General Hospital, The University of Sydney, Sydney, Australia Prince of Wales Medical Research Institute, Randwick, Australia
David A. Grayson
Affiliation:
Department of Psychology, The University of Sydney, Sydney, Australia
G. Anthony Broe
Affiliation:
Prince of Wales Medical Research Institute, Randwick, Australia
Robyn L. Tate
Affiliation:
Rehabilitation Studies Unit, Department of Medicine, The University of Sydney, Sydney, Australia
Hayley P. Bennett
Affiliation:
Prince of Wales Medical Research Institute, Randwick, Australia
Tanya C. Lye
Affiliation:
Centre for Education & Research on Ageing at Concord Repatriation General Hospital, The University of Sydney, Sydney, Australia
Helen Creasey
Affiliation:
Centre for Education & Research on Ageing at Concord Repatriation General Hospital, The University of Sydney, Sydney, Australia
Lloyd Ridley
Affiliation:
Department of Radiology, Concord Repatriation General Hospital, Concord, Australia
Get access

Abstract

Background: Studies on normal aging and cognitive functioning commonly describe early and more pronounced age-related changes in executive functions (EFs) compared to other cognitive abilities. Two of the three most common neurodegenerative disorders associated with aging (vascular dementia [VaD] and extrapyramidal [EP]-related dementia) show executive dysfunctions in their clinical presentation; and these cognitive deficits are not uncommon in the third one: Alzheimer's disease (AD). Methods: Nine EF tests (yielding 12 measures) were administered to 123 randomly selected community dwellers, aged 81 years and over, with the view to determine the effect of age on performance. Markers of AD, VaD, and EP-related dementia, as well as sociodemographic and psychological variables, were selected and their contribution to EF performance was investigated. Results: Multiple linear regression analyses revealed the greatest contribution to EF scores from the markers of AD and estimated IQ but not from the markers of VaD and EP-related dementia or from age. Conclusions: These findings suggest that chronological age acts as a proxy variable mediating the impact of other factors such as subclinical signs of neurodegenerative disorders and that it has little independent contribution to make. They also indicate the importance of cognitive abilities supported by posterior cortical circuits in EF problem resolution. This study demonstrates that cognitive decline is not an ineluctable process that is associated with “normal” aging but rather represents, in many cases, a byproduct of neurodegenerative disorders, albeit themselves highly age-related.

Type
Articles
Copyright
© 2002 International Psychogeriatric Association

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)