PURPOSE: Subarachnoid hemorrhage (SAH) is a common reason for admission to the ICU and is associated with significant morbidity, mortality, and resource utilization. We sought to evaluate from a population-based registry the profile and outcomes of patients admitted with SAH to US non-federal hospitals during the 10 year period from 1998 to 2007.
METHODS: All adult inpatient admissions with a primary diagnosis of SAH (ICD9-CM2 code 430)from 1998 to 2007 were identified from the Nationwide Inpatient Sample (NIS), a database administered by the Agency for Healthcare Research and Quality (AHRQ). Primary outcome was in-hospital mortality. Univariate and multivariate regressions were used to derive odds ratios. The Cochran-Armitage Trend test was used where independent variables were ordinal. All analyses were performed using SAS(V9.2.3, Cary, NC).
RESULTS: A total of 50,895 admissions for SAH were identified. Patinets were more likely to be female (63.2%) and Caucasian (66.6%). Significanlty more admissions were in the fall compared to other seasons (p<0.001). Overall mortality was 25.2%, decreasing from 28.8% in 1998 to 21.4% in 2007 (p<0.001). After adjustment for covariates, mortality was associated with increasing age(OR=4.0; 95%CI 3.3-4.2 for oldest vs youngest group), female gender (OR=1.07; 95%CI 1.02-1.13), Asian/pacific islander ethnicity (OR=1.2; 95%CI 1.1-1.4), as well as co-morbid liver disease (OR=1.8; 95%CI 1.5-2.2), renal failure (OR=1.7; 95%CI 1.5-2.0), and coagulopathy (OR=1.6; 95%CI 1.4-1.7). Pulmonary circulation disease appeared to be protective (OR=0.7; 95%CI 0.5-0.9). Admissions to the northeastern, medium-sized, or urban/non-teaching hospital were independently associated with worse outcome. Mortality was higher when the primary payer was Medicare (OR=1.2; 95%CI 1.1-1.3), Medicaid (OR=1.3; 95%CI 1.2-1.5), or self-pay (OR=1.9; 95%CI=1.7-2.1).
CONCLUSION: Significant improvements in mortality due to SAH were made during the 1998-2007 period. Additional studies are needed to explain the higher odds of mortality in the northeast, medium, and urban/non-teaching hospitals, as well as the apparent protective effect of co-morbid pulmonary circulation disease.
CLINICAL IMPLICATIONS: SAH remains a diagnosis associated with high in-hospital mortality. To further reduce mortality patients may be referred to the regional “centers of excellence”.
DISCLOSURE: Maksim Zayaruzny, No Financial Disclosure Information; No Product/Research Disclosure Information