Cognition and mortality in older people: The Sydney Memory and Ageing Study

Michael H. Connors, Perminder S. Sachdev, Nicole A. Kochan, Jing Xu, Brian Draper, Henry Brodaty*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

32 Citations (Scopus)

Abstract

Background: both cognitive ability and cognitive decline have been shown to predict mortality in older people. As dementia, a major form of cognitive decline, has an established association with shorter survival, it is unclear the extent to which cognitive ability and cognitive decline predict mortality in the absence of dementia.Objective: to determine whether cognitive ability and decline in cognitive ability predict mortality in older individuals without dementia.Design: the Sydney Memory and Ageing Study is an observational population-based cohort study. Participants completed detailed neuropsychological assessments and medical examinations to assess for risk factors such as depression, obesity, hypertension, diabetes, hypercholesterolaemia, smoking and physical activity. Participants were regularly assessed at 2-year intervals over 8 years.Setting: a community sample in Sydney, Australia.Subjects: one thousand and thirty-seven elderly people without dementia.Results: overall, 236 (22.8%) participants died within 8 years. Both cognitive ability at baseline and decline in cognitive ability over 2 years predicted mortality. Decline in cognitive ability, but not baseline cognitive ability, was a significant predictor of mortality when depression and other medical risk factors were controlled for. These relationships also held when excluding incident cases of dementia.Conclusions: the findings indicate that decline in cognition is a robust predictor of mortality in older people without dementia at a population level. This relationship is not accounted for by co-morbid depression or other established biomedical risk factors.

Original languageEnglish
Article numberafv139
Pages (from-to)1049-1054
Number of pages6
JournalAge and Ageing
Volume44
Issue number6
DOIs
Publication statusPublished - 1 Nov 2015
Externally publishedYes

Keywords

  • cognition
  • cognitive impairment
  • dementia
  • mortality
  • older people

Fingerprint

Dive into the research topics of 'Cognition and mortality in older people: The Sydney Memory and Ageing Study'. Together they form a unique fingerprint.

Cite this