Lack of relationship between leukoaraiosis and carotid artery disease. The North American Symptomatic Carotid Endarterectomy Trial
J. Y. Streifler, M. Eliasziw, O. R. Benavente, V. C. Hachinski, A. J. Fox and H. J. Barnett
Department of Clinical Neurological Sciences, University of Western Ontario, London.
OBJECTIVE: Leukoaraiosis (LA) (white matter changes) is frequently observed
on computed tomographic scans of the brain of elderly patients at risk of
stroke. A localized vascular-ischemic cause has been suggested for its
underlying mechanism. Our aim was to assess whether high-grade carotid
stenosis is associated with LA. DESIGN/SETTING: Patients enrolled in the
North American Symptomatic Carotid Endareterectomy Trial (also known as
NASCET) were evaluated for LA using a recently proposed grading scale.
Ordinal regression analysis was used to assess the association between the
severity of carotid artery stenosis and the extent of LA observed on
computed tomographic scans. The patients' brain hemisphere was selected as
the unit of analysis. RESULTS: Of the 2394 brain hemispheres contributed to
the analyses, 352 (14.7%) had signs of LA. After controlling for known
stroke risk factors in the ordinal regression analysis, only the history of
stroke and increasing age were significantly related to LA. Severity of
stenosis was observed to be unrelated (odds ratio [severe vs mild stenosis]
= 1.08; 95% confidence interval, 0.73-1.62; P = .952) as were a history of
hypertension and a history of myocardial infarction. CONCLUSION:
Leukoaraiosis is not associated with severe carotid artery stenosis.