Executive dysfunction is a strong stroke predictor

Background: Although stroke is known to result in executive dysfunction, little is known about executive dysfunction as a risk factor for stroke. Methods: Canadian Study of Health and Aging (CSHA), a longitudinal population based study of elderly Canadians, was conducted in three waves in 1990-1991 (CSHA-1), 1995-1996 (CSHA-2), and 2001-2002 (CSHA-3). In a cross-sectional analysis on CSHA-1 subjects, any association between stroke history and cognitive function was studied. In a prospective analysis, CSHA-1 stroke-free subjects were followed to CSHA-2 to see if there was any difference in stroke incidence among subjects with different baseline cognitive status. And, in a validation study CSHA-2 stroke-free subjects were followed to CSHA-3 to see if the prospective analyses findings could be replicated. Findings: In the cross-sectional analysis, subjects who had stroke in their history had significantly lower executive function, not memory function, scores than subjects without any stroke in their history. In the prospective and validation studies, stroke incidence was affected by neither executive nor memory scores. When the analysis was restricted to normal cognition subjects, lower executive function, not memory function, scores predicted stroke incidence, and remained significant after controlling for stroke risk factors. Conclusion: We found executive dysfunction to be a powerful stroke risk factor among cognitively normal subjects. Testing for executive dysfunction may help identify individuals at risk for stroke in time to prevent them. (C) 2015 Elsevier B.V. All rights reserved.