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Published on: January 4, 2013
Smokers with Large Vessel Occlusion Stroke Show Poor Leptomeningeal Collaterals
Hakim Baazaoui1, Francesco Morra1, Lukas Bastian Otto1
1From the Department of Neurology (H.B., L.B.O., G.M.G., C.L., M.E.A., M.G., S.W.), University Hospital Zurich and University of Zurich, Zurich, Switzerland; Department of Neuroradiology (F.M.), EOC Ospedale Regionale di Lugano, Lugano, Switzerland; Neuroscience Center Zurich (C.L., M.E.A., P.T., Z.K., S.W.), ETH and University of Zurich, Zurich, Switzerland; ARTORG Center for Biomedical Engineering Research (C.L.), University of Berne, Berne, Switzerland; Department of Clinical Research (S.P., T.D.D.), University of Basel, Basel, Switzerland; Department of Neurology and Stroke Center (S.P., T.D.D.), University Teaching and Research Hospital, Health Eastern Switzerland (HOCH), Cantonal Hospital St. Gallen, St. Gallen, Switzerland; Department of Neuroradiology (P.T., Z.K.), University Hospital Zurich, Zurich, Switzerland.
Background And Purpose:
In ischemic stroke, the collateral circulation influences tissue survival, but the factors that affect collateral function remain understudied. Smoking is a major vascular risk factor, yet some studies have suggested a "smokers' paradox", with increased resilience of the brain's vascular network and better outcomes in patients with a positive smoking history. Here, we aimed to assess associations between smoking and leptomeningeal collateral status using DSA, the reference standard for collateral evaluation.
Methods:
We retrospectively analysed data from 921 patients with confirmed vessel occlusion from our multicentre stroke image and clinical data repository. Leptomeningeal collaterals were graded based on DSA. Smoking status was classified as never versus former or current smoker. Univariate and multivariate analyses were used to investigate the associations between smoking and collateral status, adjusting for relevant clinical features.
Results:
357 patients were included in the analysis (53% women), 19% were current or former smokers. Stroke patients with a positive smoking history were significantly younger and less likely to have atrial fibrillation. In unadjusted and adjusted logistic regression analysis, smokers had significantly lower odds of having a good collateral status on DSA with an unadjusted odds ratio of 0.43 (95% CI: 0.24 - 0.75) and an adjusted odds ratio of 0.42 (95% CI: 0.23 - 0.76).
Conclusions:
DSA-based assessment demonstrated a significant association between positive smoking history and worse collateral status. These findings contradict prior CTA-based studies and the "smokers' paradox" hypothesis.
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