2012 HSR&D/QUERI National Conference Abstract
3053 — Wide Variation in 30-day Mortality After Severe Sepsis in VA Hospitals
Iwashyna TJ, VA Center for Clinical Management Research & University of Michigan; Kennedy EH, and Wiitala WL, VA Center for Clinical Management Research; Cooke CR, University of Michigan; Sales AE, VA Inpatient Evaluation Center;
Severe sepsis is a syndrome in which an infection leads to acute organ dysfunction; it is increasingly common. Recently, several therapies have proven effective for severe sepsis, but their delivery requires interdisciplinary coordination. We sought to assess the extent to which there is variation between VA hospitals in 30-day mortality after hospitalization for severe sepsis, and whether that variation was attributable to a volume/outcome relationship.
We examined 35,946 hospitalizations for severe sepsis admitted to 129 VA medical centers during 2009. Severe sepsis was ascertained using a common, clinically validated algorithm. Clinical risk adjustment was performed with data from the VA Inpatient Evaluation Center, including lab values, and indicators for primary and comorbid diagnoses. We nonparametrically estimated patient-level prognostic scores representing the risk of death conditional on treatment at a high-volume hospital. We examined the hospital contribution to 30-day mortality using multilevel models with a random intercept for each hospital. The extent of interhospital variation in 30-day mortality was quantified using the intraclass correlation coefficient (ICC) and median odds ratio.
The median VA hospital cared for 242 patients with severe sepsis in 2009, ranging from 4 to 805. 17.1% of these patients died within 30 days of admission. After reliability-adjustment and risk-adjustment to the median patient, adjusted hospital mortality varied from 7.8% to 16.5%. The ICC for the hospital-level variation was 1.33% (95% CI: 0.9%, 2.1%), with a median odds ratio of 1.22 (95% CI: 1.17, 1.29). There was a statistically significant but clinically small volume/outcome association.
Severe sepsis is a common condition at most VA hospitals, yet VA hospitals vary widely and in clinically meaningful ways in their outcomes.
The variation in 30-day mortality for severe sepsis suggests that there are opportunities for improvements for Veterans with this common condition. The relatively flat volume-outcome curve suggests that even hospitals with smaller sepsis populations can provide good outcomes—and, conversely, that simply caring for many severe sepsis patients is no guarantee of excellence. The statistical profiles of the system suggest that improvements in sepsis care may be better achieved by quality improvement efforts than hospital-level reporting.