Active Cognitive Lifestyle Is Associated with Positive Cognitive Health Transitions and Compression of Morbidity from Age Sixty-Five

Riccardo E Marioni,Michael J Valenzuela,Fiona E Matthews,Ardo Van Den Hout,Carol Brayne,Richard Fielding

doi:10.1371/journal.pone.0050940

Riccardo E Marioni, Michael J Valenzuela + Show 4 more

Open Access

https://doi.org/10.1371/journal.pone.0050940

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Abstract

BackgroundThree factors commonly used as measures of cognitive lifestyle are education, occupation, and social engagement. This study determined the relative importance of each variable to long term cognitive health in those with and without severe cognitive impairment.MethodsData came from 12,470 participants from a multi-centre population-based cohort (Medical Research Council Cognitive Function and Ageing Study). Respondents were aged 65 years and over and were followed-up over 16 years. Cognitive states of no impairment, slight impairment, and moderate/severe impairment were defined, based on scores from the Mini-Mental State Examination. Multi-state modelling was used to investigate links between component cognitive lifestyle variables, cognitive state transitions over time, and death.ResultsHigher educational attainment and a more complex mid-life occupation were associated with a lower risk of moving from a non-impaired to a slightly impaired state (hazard ratios 0.5 and 0.8), but with increased mortality from a severely impaired state (1.3 and 1.1). More socially engaged individuals had a decreased risk of moving from a slightly impaired state to a moderately/severely impaired state (0.7). All three cognitive lifestyle variables were linked to an increased chance of cognitive recovery back to the non-impaired state.ConclusionsIn those without severe cognitive impairment, different aspects of cognitive lifestyle predict positive cognitive transitions over time, and in those with severe cognitive impairment, a reduced life-expectancy. An active cognitive lifestyle is therefore linked to compression of cognitive morbidity in late life.

Highlights

The ageing of modern nations is set to radically alter the nature of society, arguably with no greater impact than on the prevalence and cost implications of dementia
Projections in Australia suggest that assuming the status quo, dementia-related care in 2060 would consume the entire current health budget [5], clearly an unsustainable scenario that will force unenviable health decisions by policy makers
Given these forecasts, identification of modifiable factors that reduce the risk of developing severe cognitive impairment or encourage cognitive recovery from mild cognitive impairment (MCI) to a non-cognitively impaired state are highly sought after

Summary

Introduction

The ageing of modern nations is set to radically alter the nature of society, arguably with no greater impact than on the prevalence and cost implications of dementia. Projections in Australia suggest that assuming the status quo, dementia-related care in 2060 would consume the entire current health budget [5], clearly an unsustainable scenario that will force unenviable health decisions by policy makers. Given these forecasts, identification of modifiable factors that reduce the risk of developing severe cognitive impairment or encourage cognitive recovery from mild cognitive impairment (MCI) to a non-cognitively impaired state are highly sought after. It is possible for individuals to revert from a diagnosed MCI state back to a normal, non-impaired cognitive state over time [6]. This study determined the relative importance of each variable to long term cognitive health in those with and without severe cognitive impairment

Methods

Results

Conclusion