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Is pre-existing dementia an independent predictor of outcome after stroke? A propensity score-matched analysis

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Abstract

With an aging population, patients are increasingly likely to present with stroke and pre-existing dementia, which may lead to greater death and disability. The aim of this work was to assess the risk of all-cause mortality and poor functional outcomes after ischemic stroke in patients with and without pre-existing dementia. We conducted a multicenter cohort study of all patients presenting to 12 tertiary care institutions participating in the Registry of the Canadian Stroke Network (RCSN) with a first ischemic stroke between 2003 and 2008. Individuals with pre-existing dementia were matched using propensity-score methods with patients without dementia during their index hospitalization based on the following characteristics: age (within 3 years), sex, stroke severity, stroke subtype (lacunar vs. non-lacunar), level of consciousness, vascular risk factors, dysphagia, glucose and creatinine on admission, Charlson index, residence prior to hospitalization (home vs. other), pre-admission dependency, hospital arrival via ambulance, admission to stroke unit, thrombolysis, and palliative care. A propensity score for all-cause mortality and clinical outcomes was developed. Registry of the Canadian Stroke Network (RCSN) and Registered Persons Database (RPDB). The primary outcome was all-cause mortality at 30 days. Secondary outcomes included mortality at discharge and at 1 year, disability at discharge (modified Rankin scale ≥ 3), medical complications (pneumonia), and discharge disposition. A subgroup analysis assessing the risk of intracerebral hemorrhage among those receiving thrombolysis was also conducted. We matched 877 patients with an acute ischemic stroke and pre-existing dementia to 877 stroke patients without dementia. Patients were well matched. The mean age was 82 years and 58 % were women. Mortality at discharge, 30 days, and 1 year after stroke was similar in patients with and without dementia [for mortality at discharge RR 0.88 [95 % confidence interval (CI) 0.74–1.05]; mortality at 30-days: RR 0.88 (95 % CI 0.75–1.03) and mortality at 1 year: RR 1.01 (95 % CI 0.92–1.11). Patients with pre-existing dementia had similar disability at discharge and home disposition. In the subgroup of patients who received thrombolysis, there were no differences between those with and without dementia in the risk of intracerebral hemorrhage (RR 1.27; 95 % CI 0.69–2.35) and no differences in mortality or disability at discharge. Pre-existing dementia is not independently associated with mortality, disability, or institutionalization after ischemic stroke. Pre-existing dementia may not necessarily preclude access to thrombolytic therapy and specialized stroke care.

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References

  1. Canadian study of health and aging (1994) Study methods and prevalence of dementia. CMAJ 150:899–913

    Google Scholar 

  2. Public Health Agency of Canada (2009) Tracking heart disease and stroke in Canada. Ottawa

  3. Pimlott NJ, Persaud M, Drummond N, Cohen CA, Silvius JL, Seigel K, Hollingworth GR, Dalziel WB (2009) Family physicians and dementia in Canada: part 2. Understanding the challenges of dementia care. Canadian family physician Medecin de famille canadien 55(508–509):e501–e507

    Google Scholar 

  4. Pimlott NJ, Persaud M, Drummond N, Cohen CA, Silvius JL, Seigel K, Hollingworth GR, Dalziel WB (2009) Family physicians and dementia in Canada: part 1. clinical practice guidelines: awareness, attitudes, and opinions. Canadian family physician Medecin de famille canadien 55(506–507):e501–e505

    Google Scholar 

  5. Rockwood K, Keren R (2010) Dementia services in Canada. Int J Geriatr Psychiatry 25:876–880

    Article  PubMed  Google Scholar 

  6. Canada PHA (2009) Tracking heart disease and stroke in Canada

  7. Wimo A, Prince M (2010) Alzheimer’s disease international world Alzheimer report 2010: the global economic impact of dementia

  8. Barba R, Morin MD, Cemillan C, Delgado C, Domingo J, Del Ser T (2002) Previous and incident dementia as risk factors for mortality in stroke patients. Stroke 33:1993–1998

    Article  PubMed  Google Scholar 

  9. Desmond DW, Moroney JT, Sano M, Stern Y (2002) Mortality in patients with dementia after ischemic stroke. Neurology 59:537–543

    Article  PubMed  Google Scholar 

  10. Ancona C, Arca M, Saitto C, Agabiti N, Fusco D, Tancioni V, Perucci CA (2004) Differences in access to coronary care unit among patients with acute myocardial infarction in Rome: old, ill, and poor people hold the burden of inefficiency. BMC Health Serv Res 4:34

    Article  PubMed  Google Scholar 

  11. Avendano M, Glymour MM (2008) Stroke disparities in older Americans: Is wealth a more powerful indicator of risk than income and education? Stroke 39:1533–1540

    Article  PubMed  Google Scholar 

  12. van der Steen JT, Ooms ME, Ader HJ, Ribbe MW, van der Wal G (2002) Withholding antibiotic treatment in pneumonia patients with dementia: a quantitative observational study. Arch Intern Med 162:1753–1760

    Article  PubMed  Google Scholar 

  13. Bejot Y, Rouaud O, Jacquin A, Osseby GV, Durier J, Manckoundia P, Pfitzenmeyer P, Moreau T, Giroud M (2010) Stroke in the very old: incidence, risk factors, clinical features, outcomes and access to resources–a 22-year population-based study. Cerebrovasc Dis 29:111–121

    Article  PubMed  Google Scholar 

  14. Finucane TE, Christmas C, Travis K (1999) Tube feeding in patients with advanced dementia: a review of the evidence. JAMA 282:1365–1370

    Article  PubMed  CAS  Google Scholar 

  15. 2007 Organised inpatient (stroke unit) care for stroke. Cochrane Database Syst Rev. CD000197

  16. Saposnik G, Kapral MK, Coutts SB, Fang J, Demchuk AM, Hill MD (2009) Do all age groups benefit from organized inpatient stroke care? Stroke 40:3321–3327

    Article  PubMed  Google Scholar 

  17. Smith EE, Hassan KA, Fang J, Selchen D, Kapral MK, Saposnik G (2010) Do all ischemic stroke subtypes benefit from organized inpatient stroke care? Neurology 75:456–462

    Article  PubMed  CAS  Google Scholar 

  18. Kapral MK, Silver FL, Richards JA, Lindsay MP, Fang J, Shi S et al (2005) Registry of the Canadian stroke network. Progress report 2001–2005. Toronto

  19. Alberts MJ, Latchaw RE, Selman WR, Shephard T, Hadley MN, Brass LM, Koroshetz W, Marler JR, Booss J, Zorowitz RD, Croft JB, Magnis E, Mulligan D, Jagoda A, O’Connor R, Cawley CM, Connors JJ, Rose-DeRenzy JA, Emr M, Warren M, Walker MD (2005) Recommendations for comprehensive stroke centers: a consensus statement from the brain attack coalition. Stroke 36:1597–1616

    Article  PubMed  Google Scholar 

  20. Bushnell CD, Johnston DC, Goldstein LB (2001) Retrospective assessment of initial stroke severity: comparison of the NIH stroke scale and the Canadian neurological scale. Stroke 32:656–660

    Article  PubMed  CAS  Google Scholar 

  21. Cote R, Battista RN, Wolfson C, Boucher J, Adam J, Hachinski V (1989) The Canadian neurological scale: validation and reliability assessment. Neurology 39:638–643

    Article  PubMed  CAS  Google Scholar 

  22. Austin PC (2009) Balance diagnostics for comparing the distribution of baseline covariates between treatment groups in propensity-score matched samples. Stat Med 28:3083–3107

    Article  PubMed  Google Scholar 

  23. Austin PC, Grootendorst P, Anderson GM (2007) A comparison of the ability of different propensity score models to balance measured variables between treated and untreated subjects: a Monte Carlo study. Stat Med 26:734–753

    Article  PubMed  Google Scholar 

  24. Mamdani M, Sykora K, Li P, Normand SL, Streiner DL, Austin PC, Rochon PA, Anderson GM (2005) Reader’s guide to critical appraisal of cohort studies: 2 assessing potential for confunding. BMJ 330:960–962

    Article  PubMed  Google Scholar 

  25. Massoud F, Lysy P, Bergman H (2010) Care of dementia in Canada: a collaborative care approach with a central role for the primary care physician. J Nutr Health Aging 14:105–106

    Article  PubMed  CAS  Google Scholar 

  26. Snowdon DA, Greiner LH, Mortimer JA, Riley KP, Greiner PA, Markesbery WR (1997) Brain infarction and the clinical expression of Alzheimer disease. The nun study. JAMA 277:813–817

    Article  PubMed  CAS  Google Scholar 

  27. Saposnik G, Cote R, Rochon PA, Mamdani M, Liu Y, Raptis S, Kapral MK, Black SE (2011) Care and outcomes in patients with ischemic stroke with and without preexisting dementia. Neurology 77:1664–1673

    Google Scholar 

  28. Appelros P, Viitanen M (2005) What causes increased stroke mortality in patients with prestroke dementia? Cerebrovasc Dis 19:323–327

    Article  PubMed  Google Scholar 

  29. Austin PC (2008) A critical appraisal of propensity-score matching in the medical literature between 1996 and 2003. Stat Med 27:2037–2049

    Article  PubMed  Google Scholar 

  30. Henon H, Durieu I, Lebert F, Pasquier F, Leys D (2003) Influence of prestroke dementia on early and delayed mortality in stroke patients. J Neurol 250:10–16

    Article  PubMed  Google Scholar 

  31. Alshekhlee A, Li C–C, Chuang S-Y, Vora N, Edgell RC, Kitchener JM, Kale SP, Feen E, Piriyawat P, Callison RC, Cruz-Flores S (2011) Does dementia increase risk of thrombolysis? A case–control study. Neurology 76:1575–1580

    Article  PubMed  CAS  Google Scholar 

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Acknowledgments

Dr. Saposnik reports research funding from the Heart and Stroke Foundation of Canada, Canadian Institutes for Health Research, Department of Research at St. Michael’s Hospital and Connaught Foundation (University of Toronto); and salary support from the Clinician-Scientist Award from the Heart and Stroke Foundation of Ontario. Dr. Kapral holds a Career Investigator Award from the Canadian Institutes for Health Research and receives funding from the Canadian Stroke Network and the University Health Network Women’s Health Program.

Conflicts of interest

None.

Author information

Authors and Affiliations

  1. Division of Neurology, Departments of Medicine and Health Policy, Management and Evaluation, Institute for Clinical Evaluative Sciences, St. Michael’s Hospital, University of Toronto, 55 Queen St East, Suite 931, Toronto, ON, M5C 1R6, Canada

    Gustavo Saposnik

  2. Departments of Medicine and Health Policy, Management and Evaluation, Institute of Clinical Evaluative Sciences (ICES), University Health Network, University of Toronto, Ontario, Canada

    Moira K. Kapral

  3. Division of Neurology, Montreal General Hospital, McGill University, Montreal, QC, Canada

    Robert Cote

  4. Department of Medicine, Women’s College Research Institute, Women’s College Hospital, University of Toronto, Toronto, Canada

    Paula A. Rochon

  5. Institute for Clinical Evaluative Sciences, Toronto, Canada

    Julie Wang

  6. Applied Health Research Centre, St. Michael’s Hospital, Toronto, Canada

    Stavroula Raptis

  7. Applied Health Research Centre, St. Michael’s Hospital and Health Policy, Management and Evaluation, Institute for Clinical Evaluative Sciences St. Michael’s Hospital, University of Toronto, Toronto, Canada

    Muhammad Mamdani

  8. North & East Greater Toronto Area Regional Stroke Program, Heart and Stroke Foundation Centre for Stroke Recovery, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada

    Sandra E. Black

Authors
  1. Gustavo Saposnik
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  2. Moira K. Kapral
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  3. Robert Cote
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  4. Paula A. Rochon
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  5. Julie Wang
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  6. Stavroula Raptis
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  7. Muhammad Mamdani
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  8. Sandra E. Black
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Corresponding author

Correspondence to Gustavo Saposnik.

Additional information

On behalf of the Investigators of the Registry of the Canadian Stroke Network and the Stroke Outcome Research Canada (SORCan) Working Group.

Dr. M. Mamdani, S. E. Black contributed equally to this work.

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Saposnik, G., Kapral, M.K., Cote, R. et al. Is pre-existing dementia an independent predictor of outcome after stroke? A propensity score-matched analysis. J Neurol 259, 2366–2375 (2012). https://doi.org/10.1007/s00415-012-6508-4

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  • DOI: https://doi.org/10.1007/s00415-012-6508-4

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