A statistical analysis of factors related to symptomatic cerebral vasospasm.

A retrospective review of patients presenting to our institution with aneurysmal subarachnoid hemorrhage between 1980-1990 was accomplished. Eleven variables were examined as to their relationship to clinical vasospasm: age, sex, clinical grade, amount of subarachnoid blood on CT, aneurysm location, incidence of vasospasm, incidence of complications, use of calcium channel blockers, time to surgery, length of stay, and outcome. Data were analyzed with univariate and multivariate logistical regression methodology. By univariate analysis, age under 20, amount of subarachnoid hemorrhage, and clinical grade were associated with a higher risk of vasospasm. Using multivariate logistic regression, these factors, along with age under 35, were correlated as being predictive of clinical vasospasm. When all patients are grouped into either good or bad outcome, and a similar analysis is performed, only in the poor outcome group is the amount of subarachnoid hemorrhage and clinical grade correlated with vasospasm. This suggests that there is a group of patients with a predisposition to vasospasm that is independent of subarachnoid hemorrhage and clinical grade, and that these patients may have a more favorable outcome.