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

Abstract Background Register-based studies are common in sepsis epidemiology. Chart review is considered gold standard but is time consuming. This is one of few such studies. Methods In 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. Results Among 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. Conclusions The 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 bacteremia per se. Even after ten years, mortality is increased in both sepsis groups. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement Yes ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The original study was approved by the Ethical Review Board at the University of Gothenburg (permit 376/2011). The 10-year follow up was approved by the Swedish Ethical Review Authority (2022-04814-02). I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All original data will be made available if the article is accepted. They were published after the first article was accepted in your journal in 2019, but currently I don't know where they can be found.