Association between seizures and mortality in patients with aneurysmal subarachnoid hemorrhage: A nationwide retrospective cohort analysis

PURPOSE The impact of seizures on outcomes in patients with subarachnoid hemorrhage (SAH) is not well understood, with conflicting results published in the literature. METHOD For this retrospective cohort analysis, data from the Nationwide Inpatient Samples (NIS) for 2006-2011 were utilized. All patients aged ≥18 years with a primary admitting diagnosis of subarachnoid hemorrhage were included. Patients with a diagnosis of seizure were segregated from the initial cohort. Multivariable logistic regression modeled the risk of death while adjusting for severity of SAH as well as co-morbidities. The primary outcome of this analysis was in-hospital mortality. RESULTS 12,647 patients met inclusion criteria for the study, of which 1336 had a diagnosis of seizures. The unadjusted in-hospital mortality was higher for patients with seizures compared to those without (16.2% vs 11.6%, p<0.01). Compared to patients without seizures, patients with seizures were younger (52.4 years SD 13.9 vs 54.8 years, SD 13.6; p<0.01), more likely to be male (35.6% vs 31.0%, p<0.01) and had longer hospital stays (18.3 days, IQR 12.0-27.5 vs 14.8 days, IQR 10.0-21.9; p<0.01). After adjusting for the severity of SAH, seizures were found to be associated with increased mortality (OR 1.57, 95% CI 1.32-1.87, p<0.01). CONCLUSION In this large nationwide analysis, the presence of seizures in patients with SAH was associated with higher in-hospital mortality. This finding has potentially important implications for goals of care decision-making and prognostication, but further study in the area is needed.