Outcome of community onset severe sepsis, Sepsis-3 sepsis, and bacteremia in Sweden – a prospective population-based study

Abstract

AbstractBackgroundRegister-based studies are common in sepsis epidemiology. Chart review is considered gold standard but is time consuming. This is one of few such studies.MethodsIn a 9-month prospective and consecutive study conducted in 2011-12, chart review was used to investigate outcomes in patients with severe sepsis, Sepsis-3 sepsis, and bacteremia in a population of 256,700 inhabitants in southwest Sweden. All adult patients aged ≥18 years admitted to hospital and given intravenous antibiotic treatment within 48 hours were evaluated, N=2,196. Cohort mortality was calculated up to 10 years after admission.ResultsAmong 2,072 adults with any infection, 429 patients had severe sepsis of which 59 had septic shock. The 28-day case fatality rate (CFR) was 25%, 41% in those with septic shock. Sepsis-3 sepsis was diagnosed in 1,299 patients. The 28-day CFR was 12%. Among the 1,299, 393 also had severe sepsis. In 906 patients with Sepsis-3 sepsis but not severe sepsis, the 28-day CFR was 6%. For both sepsis definitions, the 28-day CFR increased 10-fold between the youngest and the oldest age groups. Age >75 years, and renal dysfunction were the strongest independent risk factors for 28-day case fatality. Bacteremia occurred in 283/2,072 (13%) patients. The 28-day CFR was 13% overall, 25% in severe sepsis and 4% in non-severe sepsis. Even 10 years after admission, the mortality rate was higher in sepsis patients by either definition.ConclusionsThe 28-day case fatality rate (CFR) in patients with Sepsis-3 sepsis, 12%, is the result of a large group of patients with a low 28-day CFR, 6%, camouflaging a group with severe sepsis and a high 28-day CFR, 25%. Age >75 years is an independent risk factor for case fatality. The 28-day CFR in patients with bacteremia is a function of severe sepsis, not bacteremiaper se. Even after ten years, mortality is increased in both sepsis groups.