Infection-related hospital readmissions after surviving sepsis: a retrospective population level study of adult sepsis survivors in Australia

Objectives Among adult sepsis survivors we aimed to: (i) assess the rate of all-cause, sepsis or infection hospital readmissions, and (ii) identify associated risk factors. Methods Retrospective cohort study of adult sepsis survivors with an index hospital admission between Jan 1, 2015, and Jan 31, 2021, in any hospital in New South Wales, Australia. The primary outcome was all-cause, sepsis or infection readmission through the emergency department (ED) within 30 days. Secondary outcomes were 7- and 90-day readmissions. Risk factors were investigated using multivariable logistic regression modelling. Results Within 30 days, 18,731 (14.9%) of the 125,370 adult sepsis survivors had an all-cause readmission through the ED. Of these readmissions, 1910 (10.2%) had a sepsis diagnosis and 4790 (25.6%) had an infection diagnosis. Factors associated with a higher risk of sepsis or infection-related readmission within 30 days were male sex, not being married, and chronic pulmonary disease, liver disease, diabetes, renal disease, malignancies, or malignant tumour comorbidities. In contrast, factors associated with a lower risk of sepsis or infection-related readmission were being aged 16–44 years (compared to survivors aged >85 years), living in inner regional areas (compared to major cities), or living in the least socioeconomically disadvantaged area (compared to the most), and myocardial infarction, cerebrovascular disease, or peptic ulcer disease comorbidities. Conclusion Early and unexpected hospital readmissions are common in Australian sepsis survivors with almost 15% returning to hospital through the ED within 30 days, a third of which were for another sepsis or infection event.