Calcium antagonists for ischemic stroke - A systematic review

Background and Purpose-Stroke is a common disease, and many trials with cal cium antagonists as possible neuroprotective agents have been conducted. Th e aim of this review is to determine whether calcium antagonists reduce the risk of death or dependency after acute ischemic stroke. Methods-Acute stroke trials were identified with help of the Cochrane Colla boration Stroke Group and personal contacts. All randomized trials (publish ed and unpublished) investigating a calcium antagonist (acting on voltage-s ensitive as main outcome. Analyses were, if possible, "intention-to-treat"; pooled relative risks with 95% CIs were calculated. Results-Forty-seven trials were identified, of which 29 were included (7665 patients). No effect of calcium antagonists on poor outcome at the end of follow-up (relative risk, 1.04; 95% CI, 0.98 to 1.09) or on death at end of follow-up (relative risk, 1.07; 95% CI, 0.98 to 1.17) was found. Sensitivi ty analyses on route of administration and time interval between stroke and start of treatment showed no effect on outcome. Ln subgroups of unpublishe d and methodologically sound trials, a statistically significant negative e ffect for calcium antagonists was found. This contrasts with results of pub lished trials and trials of moderate or poor methodological quality. Conclusions-The presented evidence rules out a clinically important effect of calcium antagonists after ischemic stroke. The large amount of data lead s to narrow CIs with no significant heterogeneity, and the overall results are therefore likely to be statistically robust.