Duration between aneurysm rupture and treatment - association with outcome in aneurysmal subarachnoid haemorrhage

Introduction: Timely treatment of aneurysmal subarachnoid haemorrhage (aSAH) is key to prevent further rupture and poor outcome. We evaluated complications and outcome adjusting for time from haemorrhage to treatment. Methods: : Retrospective analysis of aSAH patients admitted between 2006 and 2020. Data was collected using standardized case report forms. We compared risk factors using multivariable logistic regression. Results: : We included 853 patients, 698 (81.8%) were treated within 24 hours. Patients with higher Hunt and Hess grades were admitted and treated significantly faster than those with lower grades (overall p-value<0.001). Fifteen patients (1.8%) rebled before intervention. In the multivariable logistic analysis adjusting for timing, Barrow Neurological Institute score and intracerebral haemorrhage were significantly associated with rebleeding (overall p-value 0.006; OR 3.12, 95%CI 1.09-8.92, p=0.03, respectively). Treatment >24 hours was associated with higher mortality and cerebral infarction in lower grades aSAH (OR 3.13, 1.02-9.58 95%CI, p-value=0.05; OR 7.69, 2.44-25.00, p-value<0.001, respectively). Conclusion: Treatment >24 hours after rupture is associated with higher mortality and cerebral infarction rates in lower grades aSAH. Delay in treatment with consequently higher complication rates primarily affects patients with lower grade aSAH. Patients with lower grade aSAH ought to be treated with the same urgency as higher-grade aSAH.