Inpatient hospital performance is associated with post-discharge sepsis mortality

Abstract

Background: Post-discharge deaths are common in patients hospitalized for sepsis, but the drivers of post-discharge deaths are unclear. The objective of this study was to test the hypothesis that hospitals with high risk-adjusted inpatient sepsis mortality also have high post-discharge mortality, readmissions, and discharge to nursing homes.

Methods: Retrospective cohort study of age-qualifying Medicare beneficiaries with sepsis hospitalization between January 2013 and December 2014. Hospital survivors were followed for 180-days post-discharge, and mortality, readmissions, and new admission to skilled nursing facility were measured. Inpatient hospital-specific sepsis risk-adjusted mortality ratio (observed: expected) was the primary exposure.

Results: A total of 830,721 patients in the cohort were hospitalized for sepsis, with inpatient mortality of 20% and 90-day mortality of 48%. Higher hospital-specific sepsis risk-adjusted mortality was associated with increased 90-day post-discharge mortality (aOR 1.03 per each 0.1 increase in hospital inpatient O:E ratio, 95% CI 1.03-1.04). Higher inpatient risk adjusted mortality was also associated with increased probability of being discharged to a nursing facility (aOR 1.03, 95% CI 1.02-1.03) and 90-day readmissions (aOR 1.03, 95% CI 1.02-1.03).

Conclusions: Hospitals with the highest risk-adjusted sepsis inpatient mortality also have higher post-discharge mortality and increased readmissions, suggesting that post-discharge complications are a modifiable risk that may be affected during inpatient care. Future work will seek to elucidate inpatient and healthcare practices that can reduce sepsis post-discharge complications.

Keywords: Patient discharge; Patient readmission; Quality of health care; Sepsis.

Fig. 1

Proposed causal diagram for the hypothesized relationship between hospital-specific observed:expected (O:E) mortality ratio and post-discharge mortality. Shaded boxes indicate parameters that are measurable (non-shaded boxes are unmeasured). In our primary analysis, we are using inpatient O:E mortality as a surrogate approximation of hospital quality. The purpose of this analysis is to understand to what degree post-discharge mortality may be modifiable based on hospital-level care

Fig. 2

Flow diagram of study subjects. Non-index sepsis encounters include prior admissions, readmissions, transfers (at the receiving hospital), and skilled nursing facility admissions

Fig. 3

Cox proportional hazard model curves showing adjusted time-to mortality (a) and time-to-readmission (b) for patients who survive a sepsis hospitalization. Curves are stratified into cohorts defined by the quartile of observed:expected (O:E) in-hospital sepsis mortality aggregated at the level of the hospital. Survival analysis is adjusted for age, race, sex, comorbidities, infection source, organ dysfunction, skilled nursing facility residence prior to admission, community factors (percent Black, percent Hispanic, percent with high school degree or higher, percent below poverty line), ICU services in hospital, teaching hospital