Magnesium for treatment of acute lacunar stroke syndromes: further analysis of the IMAGES trial

Aslanyan, S., Weir, C.J., Muir, K.W. and Lees, K.R. (2007) Magnesium for treatment of acute lacunar stroke syndromes: further analysis of the IMAGES trial. Stroke, 38(10), pp. 1269-1273. (doi: 10.1161/01.STR.0000259628.94421.09)

Abstract

<p><b>Background and Purpose:</b> A prespecified interaction analysis of the neutral Intravenous Magnesium Efficacy in Stroke (IMAGES) trial revealed significant benefit from magnesium (Mg) in patients with noncortical stroke. Post hoc analysis indicated that this effect was seen in lacunar clinical syndromes (LACS), interaction P=0.005. We have now examined whether this interaction could be explained by confounding baseline factors.</p> <p><b>Methods:</b> LACS was defined on the basis of neurological signs and did not include imaging. We investigated the interaction between baseline variables and Mg treatment on global outcome. We used logistic-regression models to test whether the Mg-LACS interaction remained significant after adjusting for stratification variables, sex, a novel stroke severity score, and baseline variables that had an interaction with treatment (P<0.1).</p> <p><b>Results:</b> The Mg (n=383) and placebo (n=382) groups of LACS patients were well matched on baseline factors. In addition to LACS, we found an interaction between beneficial Mg treatment effect and younger age (P=0.003), higher baseline diastolic blood pressure (P=0.02), higher mean blood pressure (P=0.02), and absence of ischemic heart disease (P=0.07). Even so, the adjusted Mg-LACS interaction remained significant (odds ratio [OR] 0.57; 95% CI, 0.39 to 0.83; P=0.003). In the LACS subgroup, Mg improved Barthel Index <95 (OR 0.73; 95% CI, 0.55 to 0.98), modified Rankin Scale >1 (OR 0.67; 95% CI, 0.50 to 0.91), and global outcome (OR 0.70; 95% CI, 0.53 to 0.92) but not Barthel Index <60 or mortality.</p> <p><b>Conclusions:</b> The positive treatment effect of Mg in LACS cannot be ascribed to general issues of severity, time to treatment, blood pressure, or other baseline factors; equally, this finding may be due to chance. A large trial of Mg treatment in LACS appears justified.</p>

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Lees, Professor Kennedy and Muir, Professor Keith
• Authors: Aslanyan, S., Weir, C.J., Muir, K.W., and Lees, K.R.
• College/School: College of Medical Veterinary and Life Sciences > School of Cardiovascular & Metabolic Health; College of Medical Veterinary and Life Sciences > School of Psychology & Neuroscience
• Journal Name: Stroke
• Publisher: American Heart Association
• ISSN: 0039-2499
• ISSN (Online): 1524-4628
• Copyright Holders: Copyright © 2007 American Heart Association
• First Published: First published in Stroke 38(10):1269-1273
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher