Objectives: There is systematic variation between hospitals in their care of severe sepsis, but little information on whether this variation impacts sepsis-related mortality, or how hospitals' and health-systems' impacts have changed over time. We examined whether hospital and regional organization of severe sepsis care is associated with meaningful differences in 30-day mortality in a large integrated health care system, and the extent to which those effects are stable over time.
Design: In this retrospective cohort study, we used risk- and reliability-adjusted hierarchical logistic regression to estimate hospital- and region-level random effects after controlling for severity of illness using a rich mix of administrative and clinical laboratory data.
Setting: One hundred fourteen U.S. Department of Veterans Affairs hospitals in 21 geographic regions.
Patients: Forty-three thousand seven hundred thirty-three patients with severe sepsis in 2012, compared to 33,095 such patients in 2008.
Interventions: None.
Measurements and main results: The median hospital in the worst quintile of performers had a risk-adjusted 30-day mortality of 16.7% (95% CI, 13.5%, 20.5%) in 2012 compared with the best quintile, which had a risk-adjusted mortality of 12.8% (95% CI, 10.7%, 15.3%). Hospitals and regions explained a statistically and clinically significant proportion of the variation in patient outcomes. Thirty-day mortality after severe sepsis declined from 18.3% in 2008 to 14.7% in 2012 despite very similar severity of illness between years. The proportion of the variance in sepsis-related mortality explained by hospitals and regions was stable between 2008 and 2012.
Conclusions: In this large integrated healthcare system, there is clinically significant variation in sepsis-related mortality associated with hospitals and regions. The proportion of variance explained by hospitals and regions has been stable over time, although sepsis-related mortality has declined.