Mortality after Severe Sepsis and Septic Shock in Swedish Intensive Care Units 2008-2016-A nationwide observational study

Background Recent studies have reported substantially decreased hospital mortality for sepsis, but data are scarcer on outcomes after hospital discharge. We studied mortality up to 1 year in Swedish intensive care unit (ICU) patients with and without sepsis. Methods Demographic and medical data for all registered adult general ICU patients admitted between 01-01-2008 and 30-09-2016 were retrieved from the Swedish Intensive Care Registry and linked with the National Patient Register for comorbidity data and the Cause of Death Register for death dates. The population was divided in two cohorts; (a) Patients with a diagnosis of severe sepsis or septic shock and (b) All other ICU patients. Crude yearly mortality was calculated, and logistic regression was used to analyse predictors of mortality. Results 28 886 sepsis and 221 941 nonsepsis ICU patients were identified. In the sepsis cohort, in 2008 unadjusted mortality was 32.6% at hospital discharge, 32.7% at 30 days, 39% at 90 days and 46.8% at 365 days. In 2016, mortality was 30.5% at hospital discharge, 31.9% at 30 days and 38% at 90 days. Mortality at 365 days was 45.3% in 2015. Corresponding nonsepsis mortality was 15.4%, 16.2%, 20% and 26% in 2008 and 15.6%, 17.1%, 20.7% and 26.7% in 2016/2015. No consistent decrease in odds of mortality was seen in the adjusted analysis. Conclusions Mortality in severe sepsis and septic shock is high, with more than one in three patients not surviving three months after ICU admission, and adjusted mortality has not decreased convincingly in Sweden 2008-2016.