Challenges in assessing the burden of sepsis and understanding the inequalities of sepsis outcomes between National Health Systems: secular trends in sepsis and infection incidence and mortality in Germany

PURPOSE: Sepsis contributes considerably to global morbidity and mortality, while reasons for its increasing incidence remain unclear. We assessed risk adjusted secular trends in sepsis and infection epidemiology in Germany. METHODS: Retrospective cohort study using nationwide German hospital discharge data. We assessed incidence, outcomes and trends of hospital-treated sepsis and infections between 2010 and 2015. Sepsis was identified by explicit ICD-10 sepsis codes. As sensitivity analysis, results were compared with sepsis cases identified by implicit sepsis coding (combined infection and organ dysfunction codes). RESULTS: Among 18 664 877 hospital admissions in 2015, 4 213 116 (22.6%) patients had at least one infection code. There were 320 198 patients that had explicit sepsis codes including 136 542 patients with severe sepsis and septic shock; 183 656 patients were coded as sepsis without organ dysfunction. For patients with explicitly coded sepsis (including severe sepsis), or with severe sepsis alone, mortality rates over the period 2010–2015 decreased from 26.6 to 23.5%, and from 47.8 to 41.7%, respectively. CONCLUSIONS: Sepsis and infection remain significant causes of hospital admission and death in Germany. Sepsis-related mortality is higher and has declined to a lesser degree than in other high-income countries. Although infection rates steadily increased, the observed annual increase of sepsis cases seems to result, to a considerable degree, from improved coding of sepsis. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s00134-018-5377-4) contains supplementary material, which is available to authorized users.