Cognitive impairment predicts poststroke death in long-term follow-up
- N K J Oksala1,2,
- H Jokinen3,4,
- S Melkas3,
- A Oksala2,
- T Pohjasvaara3,
- M Hietanen3,4,
- R Vataja3,
- M Kaste3,
- P J Karhunen2,
- T Erkinjuntti3
- 1Division of Vascular Surgery, Department of Surgery, Tampere University Hospital, Tampere, Finland
- 2School of Medicine, Forensic Medicine, University of Tampere and the Laboratory Centre Research Unit, Tampere University Hospital, Tampere, Finland
- 3Department of Neurology, Helsinki University Central Hospital, Helsinki, Finland
- 4Department of Psychology, University of Helsinki, Helsinki, Finland
- Correspondence to Dr N Oksala, Department of Surgery and Forensic Medicine, Medical School, University of Tampere and Tampere University Hospital, 33014 University of Tampere, Finland; niku.oksala{at}tuubi1.net
- Received 3 February 2009
- Revised 13 May 2009
- Accepted 4 June 2009
- Published Online First 19 July 2009
Abstract
Background: Poststroke global cognitive decline and dementia have been related to poor long-term survival. Whether deficits in specific cognitive domains are associated with long-term survival in patients with ischaemic stroke is not known in detail.
Methods: Patients with acute stroke subjected to comprehensive neuropsychological evaluation were included in the study (n = 409) and followed up for up to 12 years.
Results: In Kaplan–Meier analysis, impairments in following cognitive domains predicted poor poststroke survival (estimated years): executive functions (48.2%) (5.8 vs 10.1 years, p<0.0001), memory (59.9%) (6.8 vs 9.3 years, p = 0.009), language (28.9%) (5.3 vs 8.6 years, p = 0.004) and visuospatial/constructional abilities (55.2%) (5.6 vs 10.1 years, p<0.0001). Low Mini Mental Status Examination (MMSE) ≤25 (30.5%) (4.4 vs 9.3 years, p<0.0001), low education (<6 years) (31.8%) (6.4 vs 8.2 years, p = 0.003) and poor modified Rankin score (39.9%) (3.9 vs 9.7 years, p<0.0001) were also related to poor survival. In Cox regression proportional hazards analyses including age, sex and years of education as covariates, deficits in executive functions (hazard ratio (HR) 1.59, p<0.0001), memory (HR 1.31, p = 0.042), language (HR 1.33, p = 0.036) and visuospatial/constructional abilities (HR 1.82, p<0.0001) were significant predictors of poor poststroke survival. Of these, executive functions (HR 1.33, p = 0.040) as well as visuospatial/constructional abilities (HR 1.53, p = 0.004) remained as significant predictors after addition of MMSE≤25 and poor modified Rankin score as covariates. Furthermore, cognitive impairment no dementia (CIND) was also an independent predictor of poor poststroke survival (HR 1.63, p = 0.0123).
Conclusions: In patients with ischaemic stroke, cognitive impairment, particularly in executive functions, and visuospatial/constructional abilities relate to poor survival.
Footnotes
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Funding This study was supported by grants from the Maire Taponen Foundation; the Paavo Nurmi Foundation; The Finnish Angiologic Association; the Medical Council of the Academy of Finland (Helsinki); the Clinical Research Institute, Helsinki University Central Hospital; the Yrjö Jahnsson Foundation (Helsinki); the Finnish Cultural Foundation and the Elli and Elvi Oksanen Fund of the Pirkanmaa Fund under the auspices of the Finnish Cultural Foundation (Tampere); the Medical Research Fund of Tampere University Hospital; the Finnish Medical Foundation; and the Finnish Foundation for Cardiovascular Research (Helsinki).
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Competing interests None.
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Ethics approval Ethics approval was provided by the Department of Clinical Neurosciences, Helsinki University Central Hospital, Finland.
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Patient consent Obtained.
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Provenance and Peer review Not commissioned; externally peer reviewed.
