AGE-RELATED MENTAL AND PHYSICAL CAPABILITY: DOES IT ALL GO TOGETHER WHEN IT GOES?

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AGE-RELATED MENTAL AND PHYSICAL CAPABILITY: DOES IT ALL GO TOGETHER WHEN IT GOES? Felicia A Huppert 1 , Brenda McWilliams 2 , Elizabeth Gardener 2 , David Melzer 3 1 Department of Psychiatry, University of Cambridge UK; 2 Department of Public Health and Primary Care, University of Cambridge UK; 3 Peninsula Medical School, University of Exeter UK While there is some degree of independence between physical and mental capability among older adults, the ageing process is associated with an average decline in both. We examined whether gait speed is related equally strongly to two aspects of cognition: memory and executive function. If gait speed is related more strongly to executive function than to memory this would provide some evidence for a causal link between executive processes and gait speed. If memory and executive function are related equally strongly to gait speed this is more consistent with a common cause hypothesis. ELSA sample approx 11,000 people aged 50+ in household sector at baseline interview every two years, starting 2002 Methods Background and aims Key topics in ELSA health trajectories disability and the compression of morbidity determinants of economic position in older age cognitive capability and later life decisions positive well-being and quality of life household/family structure; the transfer of resources social participation & social productivity at older ages We analysed cross-sectional data from the English Longitudinal Study of Ageing (ELSA). www.ifs.org.uk/elsa Cognitive measures in ELSA Memory index (maximum score = 30) – time orientation – word list learning: immediate and delayed recall – prospective memory Executive index (maximum score = 30) – verbal fluency – visual search: speed and accuracy – numerical reasoning Gait speed in ELSA Gait speed was calculated from the average time taken over two walks of eight feet each (2.44 metres). Statistical methods Logistic regression models were fitted with gait speed (dichotomised at 0.4m/sec) as the dependent variable, and cognitive indices, demographic variables (age, sex, education and wealth), and known risk factors for disability (sight, hearing, smoking status, alcohol consumption, number of diseases, pain when walking and a measure of depression (CES-D score)) as covariates. Results 0 2 4 6 8 10 12 14 Q 1 (low ) Q 2 Q 3 Q 4 Q 5 (high) Q uintiles ofcognitive indices Percentage w ith gaitspeed im pairment M em ory index Executive function index The association between cognition and gait speed was independent of and comparable in magnitude to known risk factors for disability. Gait speed was related equally strongly to memory and executive function. Our findings are consistent with a common cause hypothesis for the impairment of gait speed and cognitive function. Conclusions Sample used for analysis The sample included those aged 60 years and over, and excluded those with Alzheimer’s Disease, Parkinson’s Disease, dementia and stroke. The final sample comprised 6,615 people, 45% of whom were male. The mean age was 70 years (SD 7 years); 49% had no educational qualifications. Relationship between cognitive indices and gait speed impairment The figure shows that higher levels of performance on the memory and executive tasks were associated with higher gait speed (lower mobility disability). As expected, a number of covariates were found to be significantly associated with mobility disability: age (OR 1.09, 95% CI: 1.06 to 1.10), poor compared to excellent sight (OR 1.49, 95% CI: 1.06 to 2.13), no alcohol compared to low alcohol consumption (OR 1.64, 95% CI: 1.16 to 2.33), one compared to no diseases (OR 1.67, 95% CI: 1.02 to 2.78), high pain compared to no pain when walking (OR 3.6, 95% CI: 2.70 to 5.00) and depression score (OR 1.19, 95% CI: 1.12 to 1.27). Acknowledgements Thanks to the Health Foundation for funding the work on this analysis, to participants in ELSA for providing the data and to the ELSA team. The regression analysis showed that both cognitive indices were significantly associated with mobility disability (memory index: OR 0.93 (95% CI: 0.91 to 0.97); executive function index: OR 0.93 (95% CI: 0.89 to 0.97)).

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Felicia A Huppert 1 , Brenda McWilliams 2 , Elizabeth Gardener 2 , David Melzer 3 1 Department of Psychiatry, University of Cambridge UK; 2 Department of Public Health and Primary Care, University of Cambridge UK; 3 Peninsula Medical School, University of Exeter UK. Background and aims. - PowerPoint PPT Presentation

Transcript of AGE-RELATED MENTAL AND PHYSICAL CAPABILITY: DOES IT ALL GO TOGETHER WHEN IT GOES?

Page 1: AGE-RELATED MENTAL AND PHYSICAL CAPABILITY: DOES IT ALL GO TOGETHER WHEN IT GOES?

AGE-RELATED MENTAL AND PHYSICAL CAPABILITY: DOES IT ALL GO TOGETHER WHEN IT GOES?

Felicia A Huppert1, Brenda McWilliams2, Elizabeth Gardener2, David Melzer3

1 Department of Psychiatry, University of Cambridge UK; 2 Department of Public Health and Primary Care, University of Cambridge UK; 3 Peninsula Medical School, University of Exeter UK

While there is some degree of independence between physical and mental capability among older adults, the ageing process is associated with an average decline in both. We examined whether gait speed is related equally strongly to two aspects of cognition: memory and executive function.If gait speed is related more strongly to executive function than to memory this would provide some evidence for a causal link between executive processes and gait speed. If memory and executive function are related equally strongly to gait speed this is more consistent with a common cause hypothesis.

ELSA sample• approx 11,000 people aged 50+• in household sector at baseline• interview every two years, starting 2002

Methods

Background and aims

Key topics in ELSA • health trajectories• disability and the compression of morbidity• determinants of economic position in older age• cognitive capability and later life decisions• positive well-being and quality of life• household/family structure; the transfer of resources• social participation & social productivity at older ages

We analysed cross-sectional data from the English Longitudinal Study of Ageing (ELSA). www.ifs.org.uk/elsa

Cognitive measures in ELSA Memory index (maximum score = 30)

– time orientation

– word list learning: immediate and delayed recall

– prospective memory

Executive index (maximum score = 30)

– verbal fluency

– visual search: speed and accuracy

– numerical reasoning

Gait speed in ELSAGait speed was calculated from the average time taken over two walks of eight feet each (2.44 metres).

Statistical methodsLogistic regression models were fitted with gait speed (dichotomised at 0.4m/sec) as the dependent variable, and cognitive indices, demographic variables (age, sex, education and wealth), and known risk factors for disability (sight, hearing, smoking status, alcohol consumption, number of diseases, pain when walking and a measure of depression (CES-D score)) as covariates.

Results

0

2

4

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10

12

14

Q1 (low) Q2 Q3 Q4 Q5 (high)

Quintiles of cognitive indices

Per

cent

age

with

gai

t spe

ed im

pairm

ent

Memory index

Executive function index

• The association between cognition and gait speed was independent of and comparable in magnitude to known risk factors for disability.• Gait speed was related equally strongly to memory and executive function.• Our findings are consistent with a common cause hypothesis for the impairment of gait speed and cognitive function.

Conclusions

Sample used for analysisThe sample included those aged 60 years and over, and excluded those with Alzheimer’s Disease, Parkinson’s Disease, dementia and stroke. The final sample comprised 6,615 people, 45% of whom were male. The mean age was 70 years (SD 7 years); 49% had no educational qualifications.

Relationship between cognitive indices and gait speed impairment

The figure shows that higher levels of performance on the memory and executive tasks were associated with higher gait speed (lower mobility disability).

As expected, a number of covariates were found to be significantly associated with mobility disability: age (OR 1.09, 95% CI: 1.06 to 1.10), poor compared to excellent sight (OR 1.49, 95% CI: 1.06 to 2.13), no alcohol compared to low alcohol consumption (OR 1.64, 95% CI: 1.16 to 2.33), one compared to no diseases (OR 1.67, 95% CI: 1.02 to 2.78), high pain compared to no pain when walking (OR 3.6, 95% CI: 2.70 to 5.00) and depression score (OR 1.19, 95% CI: 1.12 to 1.27).

Acknowledgements

Thanks to the Health Foundation for funding the work on this analysis, to participants in ELSA for providing the data and to the ELSA team.

The regression analysis showed that both cognitive indices were significantly associated with mobility disability (memory index: OR 0.93 (95% CI: 0.91 to 0.97); executive function index: OR 0.93 (95% CI: 0.89 to 0.97)).