Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-08T06:32:23.120Z Has data issue: false hasContentIssue false

The cumulative effect of frailty and cognition on mortality – results of a prospective cohort study

Published online by Cambridge University Press:  01 December 2016

Philip D. St. John*
Affiliation:
Section of Geriatric Medicine, Department of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada Centre on Aging, University of Manitoba, Winnipeg, Manitoba, Canada
Suzanne L. Tyas
Affiliation:
School of Public Health and Health Systems, University of Waterloo, Waterloo, Ontario, Canada
Lauren E. Griffith
Affiliation:
Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
Verena Menec
Affiliation:
Centre on Aging, University of Manitoba, Winnipeg, Manitoba, Canada Department of Community Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
*
Correspondence should be addressed to: Philip St. John, MD MPH FRCPC, Associate Professor, Head, Section of Geriatrics, University of Manitoba, GG 441 Health Sciences Centre, 820 Sherbrook Street, R3A 1R9, Winnipeg, MB, Canada. Phone: (204) 787-3365; Fax: (204) 787-4826. Email: [email protected].

Abstract

Background:

Both physical frailty and cognitive impairment predict death, but the joint effect of these two factors is uncertain. The objectives are to determine if the Mini-mental state examination (MMSE) and the Frailty Index (FI) predict death over a five-year interval after accounting for the effect of the other; and if there is an interaction in this effect.

Methods:

An analysis of an existing prospective cohort study of 1,751 community living older adults followed over a five-year time frame. Age, gender, and education were self-reported. The predictor variables were the FI – a measure of frailty based on the “Accumulation of Deficits” model of frailty; and the MMSE. Cox proportional hazards models were constructed for the outcome of time to death.

Results:

The unadjusted Hazard Ratio (HR) (95% CI) for mortality was 2.17 (1.69, 2.80) for those who were only cognitively impaired, 2.02 (1.53, 2.68) for those who were only frail, and 3.57 (2.75, 4.62) for those who were both frail and cognitively impaired with the reference group of those who were neither frail nor cognitively impaired. Adjusted for age, gender, and education, the HR (95% CI) was 1.49 (1.13. 1.95) for those who were only cognitively impaired, 1.81 (1.35, 2.41) for those who were only frail, and 2.28 (1.69, 3.09) for those who were both frail and cognitively impaired.

Conclusions:

Both frailty and cognitive impairment are predictors of mortality and the effect is cumulative. There was no interaction in this effect.

Type
Research Article
Copyright
Copyright © International Psychogeriatric Association 2016 

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.)

References

Akaike, H. (1974). A new look at the statistical model identification. IEEE Transactions on Automatic Control, 19, 716723.CrossRefGoogle Scholar
Arnold, J. and Exton-Smith, A. N. (1962). The geriatric department and the community value of hospital treatment in the elderly. The Lancet, 280, 551553.CrossRefGoogle Scholar
Avila-Funes, J. A. et al. (2009). Cognitive impairment improves the predictive validity of the phenotype of frailty for adverse health outcomes: the three-city study. Journal of the American Geriatrics Society, 57, 453461.CrossRefGoogle ScholarPubMed
Buchman, A. S., Boyle, P. A., Wilson, R. S., Tang, Y. and Bennett, D. A. (2007). Frailty is associated with incident Alzheimer's disease and cognitive decline in the elderly. Psychosomatic Medicine, 69, 483489.CrossRefGoogle ScholarPubMed
Cano, C., Samper-Ternent, R., Al Snih, S., Markides, K. and Ottenbacher, K. J. (2012). Frailty and cognitive impairment as predictors of mortality in older Mexican Americans. Journal of Nutrition Health and Aging, 16, 142147.CrossRefGoogle ScholarPubMed
Clegg, A., Young, J., Iliffe, S., Rikkert, M. O. and Rockwood, K. (2013). Frailty in elderly people. Lancet, 381, 752762.CrossRefGoogle ScholarPubMed
Group, Csha Working. (1994). Canadian study of health and aging: study methods and prevalence of dementia. Canadian Medical Association Journal, 150, 899913.Google Scholar
Covinsky, K. E., Justice, A. C., Rosenthal, G. E., Palmer, R. M. and Landefeld, C. S. (1997). Measuring prognosis and case mix in hospitalized elders. The importance of functional status. Journal of General Internal Medicine, 12, 203208.Google ScholarPubMed
Dartigues, J. F. and Amieva, H. (2014). Cognitive frailty: rational and definition from an (I.A.N.A./I.A.G.G.) international consensus group. Journal of Nutrition Health and Aging, 18, 95.CrossRefGoogle ScholarPubMed
Dubois, M. F. and Hebert, R. (2001). Imputation of missing dates of death or institutionalization for time-to-event analyses in the Canadian study of health and aging. International Psychogeriatrics, 13 (Suppl. 1), 9197.CrossRefGoogle ScholarPubMed
Feng, L. et al. (2016). Physical frailty, cognitive impairment, and the risk of neurocognitive disorder in the singapore longitudinal ageing studies. Journals of Gerontology A Biologial Science and Medical Science. Epub ahead of print, DOI: 10.1093/gerona/glw050.CrossRefGoogle ScholarPubMed
Folstein, M. F., Folstein, S. E. and Mchugh, P. R. (1975). “Mini-mental state”. A practical method for grading the cognitive state of patients for the clinician. Journal of Psychiatric Research, 12, 189198.CrossRefGoogle ScholarPubMed
Fried, L. P. et al. (2001). Frailty in older adults: evidence for a phenotype. Journals of Gerontology A Biologial Science and Medical Science, 56, M146–M156.CrossRefGoogle ScholarPubMed
Iezzoni, L. I. (2014). Disability as a covariate in risk adjustment models for predicting hospital deaths. Annals of Epidemiology, 24, 1722.CrossRefGoogle ScholarPubMed
Jacobs, J. M., Cohen, A., Ein-Mor, E., Maaravi, Y. and Stessman, J. (2011). Frailty, cognitive impairment and mortality among the oldest old. Journal of Nutrition Health and Aging, 15, 678682.CrossRefGoogle ScholarPubMed
Kelaiditi, E., Andrieu, S., Cantet, C., Vellas, B. and Cesari, M. (2016). Frailty index and incident mortality, hospitalization, and institutionalization in Alzheimer's disease: data from the ICTUS study. Journals of Gerontology A Biologial Science and Medical Science, 71, 543548.CrossRefGoogle ScholarPubMed
Kelaiditi, E. et al. (2013). Cognitive frailty: rational and definition from an (I.A.N.A./I.A.G.G.) international consensus group. Journal of Nutrition Health and Aging, 17, 726734.CrossRefGoogle ScholarPubMed
Matusik, P. et al. (2012). Severe frailty and cognitive impairment are related to higher mortality in 12-month follow-up of nursing home residents. Archives of Gerontology and Geriatrics, 55, 2224.CrossRefGoogle ScholarPubMed
Mitnitski, A. B., Mogilner, A. J. and Rockwood, K. (2001). Accumulation of deficits as a proxy measure of aging. Scientific World Journal, 1, 323336.CrossRefGoogle ScholarPubMed
Mitnitski, A. B., Song, X. and Rockwood, K. (2004). The estimation of relative fitness and frailty in community-dwelling older adults using self-report data. Journals of Gerontology A Biologial Science and Medical Science, 59, M627–M632.CrossRefGoogle ScholarPubMed
Neale, R., Brayne, C. and Johnson, A. L. (2001). Cognition and survival: an exploration in a large multicentre study of the population aged 65 years and over. International Journal of Epidemiology, 30, 13831388.CrossRefGoogle Scholar
Porter, R. (1997). The Greatest Benefit to Mankind: A Medical History of Humanity. London: WW Norton & Co.Google Scholar
Reitz, C., Brayne, C. and Mayeux, R. (2011). Epidemiology of Alzheimer disease. Natute Reviews of Neurology, 7, 137152.CrossRefGoogle ScholarPubMed
Robertson, D. A., Savva, G. M., Coen, R. F. and Kenny, R.-A. (2014). Cognitive function in the prefrailty and frailty syndrome. Journal of the American Geriatrics Society, 62, 21182124.CrossRefGoogle ScholarPubMed
Rockwood, K. et al. (2004). Prevalence, attributes, and outcomes of fitness and frailty in community-dwelling older adults: report from the Canadian study of health and aging. Journals of Gerontology A Biologial Science and Medical Science, 59, 13101317.CrossRefGoogle ScholarPubMed
Rockwood, K. and Mitnitski, A. (2007). Frailty in relation to the accumulation of deficits. Journals of Gerontology A Biologial Science and Medical Science, 62, 722727.CrossRefGoogle Scholar
Rockwood, K. et al. (2005). A global clinical measure of fitness and frailty in elderly people. Candian Medical Assocation Journal, 173, 489495.CrossRefGoogle ScholarPubMed
Rockwood, K., Stadnyk, K., Macknight, C., Mcdowell, I., Hebert, R. and Hogan, D. B. (1999). A brief clinical instrument to classify frailty in elderly people. Lancet, 353, 205206.CrossRefGoogle ScholarPubMed
Searle, S. D., Mitnitski, A., Gahbauer, E. A., Gill, T. M. and Rockwood, K. (2008). A standard procedure for creating a frailty index. BMC Geriatrics, 8, 24.CrossRefGoogle ScholarPubMed
Sheldon, J. H. (1948). The Social Medicine of Old Age. Oxford: Oxford University Press.Google Scholar
Song, X., Mitnitski, A. and Rockwood, K. (2011). Nontraditional risk factors combine to predict Alzheimer disease and dementia. Neurology, 77, 227234.CrossRefGoogle ScholarPubMed
St John, P. D., Montgomery, P. R., Kristjansson, B. and Mcdowell, I. (2002). Cognitive scores, even within the normal range, predict death and institutionalization. Age and Ageing, 31, 373378.CrossRefGoogle ScholarPubMed
Statistics Canada. (1992). Profile of Census Metropolitan Areas and Census Agglomerations, 1991 Census – 100% Data. Ottawa, ON: Ministry of Industry,Science and Technology.Google Scholar
Teng, E. L. and Chui, H. C. (1987). The modified mini-mental state (3MS) examination. Journal of Clinical Psychiatry, 48, 314318.Google ScholarPubMed
Todd, S., Barr, S., Roberts, M. and Passmore, A. P. (2013). Survival in dementia and predictors of mortality: a review. Internatioal Journal of Geriatric Psychiatry, 28, 11091124.CrossRefGoogle ScholarPubMed
Winblad, B. et al. (2016). Defeating Alzheimer's disease and other dementias: a priority for European science and society. Lancet Neurology, 15, 455532.CrossRefGoogle ScholarPubMed