The majority of ischemic strokes are due to blockage of an artery in the brain by a blood clot. The area of brain supplied by that artery rapidly becomes damaged. Some of the damage to brain cells occurs because of a build-up of calcium ions inside the cells. Calcium antagonists might reduce the damage by preventing calcium ions entering the cells. We searched for trials which assessed the effects of calcium antagonists (given either by mouth or by intravenous injection) in patients with ischemic stroke. We found 34 studies, including 7731 patients, that were suitable for inclusion in the review. There was no difference in deaths or survival free of disability between patients who received calcium antagonists and those who did not. Patients who received calcium antagonists by intravenous injection were slightly worse overall than those who received the drugs by mouth. In conclusion, the authors of this Cochrane review found no evidence that giving calcium antagonists after acute ischemic stroke could save lives or reduce disability.
No evidence is available using calcium antagonists in patients with acute ischemic stroke is effective.
The sudden loss of blood supply in ischemic stroke is associated with the increase of calcium ions within neurons. Inhibiting this increase could protect neurons and hence might reduce neurological impairment, disability and handicap after stroke.
To determine whether calcium antagonists reduce the risk of death or dependency after acute ischemic stroke. To investigate the influence of different drugs, dosages, routes of administration, time intervals after stroke and trial design on the risk of a primary outcome.
We searched the Cochrane Stroke Group Trials Register (January 2012), MEDLINE (1950 to December 2011), EMBASE (1980 to December 2011), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2011 issue 4) and four Chinese databases (December 2011): Chinese Biological Medicine Database (CBM-disc), China National Knowledge Infrastructure (CNKI), Chinese scientific periodical database of VIP information and Wanfang Data. We also contacted trialists and researchers.
All truly randomized trials comparing a calcium antagonist with control in patients with acute ischemic stroke.
Two authors assessed all trials and extracted the data. We used death or dependency at the end of long-term follow-up (at least three months) in activities of daily living as the primary outcome. Analyses were, if possible, intention-to-treat.
We included 34 trials including 7731 patients. There was no effect of calcium antagonists on the primary outcome (risk ratio (RR) 1.05; 95% confidence interval (CI) 0.98 to 1.13), or on death at the end of follow-up (RR 1.07, 95% CI 0.98 to 1.17). Comparisons of different doses of nimodipine suggested that the highest doses were associated with poorer outcome.