Predictors of mortality in nontraumatic subdural hematoma

Abstract

Object Subdural hematoma (SDH) is a common diagnosis in neurosurgical and neurocritical practice. Comprehensive outcome data are lacking for nontraumatic SDH. The authors determined which factors are associated with in-hospital mortality in a large sample of patients with nontraumatic SDH. Methods Using the Nationwide Inpatient Sample, the authors selected adults who had been hospitalized in the US between 2007 and 2009 and in whom a primary diagnosis of nontraumatic SDH (ICD-9-CM code 432.1) had been made. Demographics, comorbidities, surgical treatment, and discharge outcomes were identified. Univariate and multivariate analyses were performed to identify predictors of in-hospital mortality. Results Among 14,093 patients with acute nontraumatic SDH, the mean age was 71.4 ± 14.8 (mean ± standard deviation). In addition, 22.2% of the patients were admitted during the weekend. Surgical evacuation was performed in 51.4% of the patients, and 11.8% of all patients died during hospitalization. In multivariate analyses, patient age (adjusted OR 1.02, 95% CI 1.012–1.022), congestive heart failure (adjusted OR 1.42, 95% CI 1.19–1.71), warfarin use (adjusted OR 1.41, 95% CI 1.17–1.70), coagulopathy (adjusted OR 2.14, 95% CI 1.75–2.61), mechanical ventilation (adjusted OR 16.85, 95% CI 14.29–19.86), and weekend admission (adjusted OR 1.19, 95% CI 1.02–1.38) were independent predictors of in-hospital mortality. Race (Hispanic: adjusted OR 0.65, 95% CI 0.51–0.83; black: adjusted OR 0.78, 95% CI 0.63–0.96), urban hospital location (adjusted OR 0.69, 95% CI 0.54–0.89), and surgical SDH evacuation (adjusted OR 0.52, 95% CI 0.45–0.60) were strong independent predictors for decreased mortality. Conclusions One in 9 patients with nontraumatic SDH dies during hospitalization. Among the several predictors of in-hospital mortality, the weekend effect and treatment with surgical evacuation are potentially modifiable factors. Further investigation may lead to improvements in management and outcomes.