Leukoaraiosis Is a Chronic Atherosclerotic Disease

Background and Purpose. White matter changes (WMCs), or leukoaraiosis (LA), are associated with increased age, hypertension, diabetes mellitus, and history of stroke. Although several lines of evidence suggest a role of atherosclerosis in atherothrombotic vascular events, their involvement in LA remains to be determined. Our study examines this association in ischemic stroke patients. Methods. One hundred and seventy consecutive ischemic stroke or transient ischemic attack (TIA) patients were included. All patients underwent brain computed tomography (CT) with assessment of the extension and severity of WMCs, carotid arteries duplex scan with measurements of intima-media thickness (IMT) and plaques. Results. Seventy-two patients (42.4%) were found to have white matter lesions, of whom 28.8% had advanced LA. Mean IMT was significantly higher in patients with LA and with advanced LA (P=0.002, P=0.003, resp.). In addition, LA and LA severity were associated with existence of carotid plaque (P=0.007, P=0.004, resp.). In multivariate logistic regression analysis, including all vascular risk factors, LA was found to be associated with age and IMT. Conclusion. This study reinforces the tight association between LA and carotid atherosclerosis in ischemic stroke patients. We conclude that a chronic atherosclerotic disease underlies the pathophysiology of leukoaraiosis and its progression

Cognitive state following stroke: the predominant role of preexisting white matter lesions.

Stroke is a major cause of cognitive impairment and dementia in adults, however the role of the ischemic lesions themselves, on top of other risk factors known in the elderly, remains controversial. This study used structural equation modeling to determine the respective impact of the new ischemic lesions' volume, preexisting white matter lesions and white matter integrity on post stroke cognitive state.Consecutive first ever mild to moderate stroke or transient ischemic attack patients recruited into the ongoing prospective TABASCO study underwent magnetic resonance imaging scans within seven days of stroke onset and were cognitively assessed one year after the event using a computerized neuropsychological battery. The volumes of both ischemic lesions and preexisting white matter lesions and the integrity of the normal appearing white matter tissue were measured and their contribution to cognitive state was assessed using structural equation modeling path analysis taking into account demographic parameters. Two models were hypothesized, differing by the role of ischemic lesions' volume.Structural equation modeling analysis of 142 patients confirmed the predominant role of white matter lesion volume (standardized path coefficient β =  -0.231) and normal appearing white matter integrity (β =  -0.176) on the global cognitive score, while ischemic lesions' volume showed no such effect (β = 0.038). The model excluding the ischemic lesion presented better fit to the data (comparative fit index 0.9 versus 0.092).Mild to moderate stroke patients with preexisting white matter lesions are more vulnerable to cognitive impairment regardless of their new ischemic lesions. Thus, these patients can serve as a target group for studies on cognitive rehabilitation and neuro-protective therapies which may, in turn, slow their cognitive deterioration

Correlation coefficients for the associations between ischemic lesions and white matter lesion volumes, white matter tissue integrity parameters and cognitive domain scores after one year.

<p>Correlation coefficients for the associations between ischemic lesions and white matter lesion volumes, white matter tissue integrity parameters and cognitive domain scores after one year.</p

Associations between white matter lesion volume and white matter tissue integrity parameters.

<p>Associations between white matter lesion volume and white matter tissue integrity parameters.</p

Structural equation models for the prediction of cognitive state after one year.

<p>Subtext: The numbers on the arcs represent the contribution of each parameter to its neighbor. * <i>p</i><0.05 **<i>p</i><0.001. Abbreviations: ILV, ischemic lesions' volume; WML, white matter lesions; NAWM, normal appearing white matter.</p

Tissue segmentation example.

<p>Subtext: A 60 year old male, scanned two days following stroke onset (A) FLAIR, fluid-attenuated inversion recovery image; (B) Ischemic lesion (blue); (C) WML, white matter lesions (yellow); (D) NAWM, normal appearing white matter (copper).</p

Summary of unadjusted and adjusted regressions for predicting global cognitive score one year after stroke.

<p>Summary of unadjusted and adjusted regressions for predicting global cognitive score one year after stroke.</p