Cognitive impairment predicts poststroke death in long-term follow-up.
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) <or=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<or=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.
Oksala
N K J
NK
Department of Surgery and Forensic Medicine, Medical School, University of Tampere and Tampere University Hospital, 33014 University of Tampere, Finland. niku.oksala@tuubi1.net
Jokinen
H
H
Melkas
S
S
Oksala
A
A
Pohjasvaara
T
T
Hietanen
M
M
Vataja
R
R
Kaste
M
M
Karhunen
P J
PJ
Erkinjuntti
T
T
D000368:Aged; D000369:Aged, 80 and over; D002423:Cause of Death; D003071:Cognition; D003072:Cognition Disorders / Q000150:complications / Q000523:psychology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D020925:Hypoxia-Ischemia, Brain / Q000150:complications / Q000523:psychology; D053208:Kaplan-Meier Estimate; D007802:Language; D008297:Male; D008568:Memory; D008875:Middle Aged; D009483:Neuropsychological Tests; D011379:Prognosis; D012307:Risk Factors; D020521:Stroke / Q000150:complications / Q000401:mortality*