Calcium antagonists for aneurysmal subarachnoid haemorrhage

Area of Science:

• Neurology
• Pharmacology
• Critical Care Medicine

Background:

• Secondary ischemia is a common complication following subarachnoid hemorrhage (SAH), often leading to poor patient outcomes.
• Vasospasm is a suspected contributing factor to secondary ischemia, and calcium antagonists have shown potential in preventing or reversing it.

Purpose of the Study:

• To evaluate the efficacy of calcium antagonists in improving outcomes for patients diagnosed with aneurysmal subarachnoid hemorrhage.

Main Methods:

• Systematic review and meta-analysis of randomized controlled trials (RCTs) comparing calcium antagonists with control treatments.
• Searched multiple databases (Cochrane Stroke Group Trials Register, MEDLINE, EMBASE) and handsearched journals; contacted trialists and pharmaceutical companies for data.
• Data extraction and quality assessment were performed independently by two reviewers.

Main Results:

• Sixteen trials involving 3361 patients were included. Calcium antagonists reduced the risk of poor outcome (Relative Risk [RR] 0.81, 95% Confidence Interval [CI] 0.72-0.92), with a Number Needed to Treat (NNT) of 19.
• Oral nimodipine monotherapy demonstrated a significant reduction in poor outcome (RR 0.67, 95% CI 0.55-0.81).
• Magnesium sulfate, as an adjunct to nimodipine, showed a trend towards reduced poor outcome (RR 0.75, 95% CI 0.57-1.00) and clinical signs of secondary ischemia (RR 0.66, 95% CI 0.45-0.96).

Conclusions:

• Calcium antagonists are effective in reducing the risk of poor outcomes and secondary ischemia in aneurysmal subarachnoid hemorrhage.
• Oral nimodipine is indicated for patients with aneurysmal SAH due to demonstrated benefits, despite some remaining uncertainties.
• Intravenous calcium antagonists are not recommended for routine use; further evidence is required for magnesium sulfate's efficacy.