Characteristics, incidence and temporal trends of sepsis in elderly patients undergoing surgery

Background: Despite increasing rates of surgery in the elderly, there is limited population-based information on sepsis in this age group. This study aimed to characterize the epidemiology and national trends of sepsis among elderly patients undergoing surgery in Spain. Methods: This population-based longitudinal study of patients aged 65 years or older, undergoing surgery between 2006 and 2011, used data from the national hospital discharge database. Patients were identified by ICD coding. Primary endpoints were incidence and case-fatality rates of sepsis. Predefined age groups were examined. In-hospital mortality-related factors were assessed by means of exploratory logistic regression. Trends were assessed for annual percentage change in rates using Joinpoint regression analysis. Results: A total of 44 342 episodes of sepsis were identified, representing 1.5 per cent of all 2 871 199 surgical hospital admissions of patients aged 65 years or older. The rates varied with age and sex. The in-hospital case-fatality rate was 43.9 per cent (19 482 patients), and associated with age, co-morbidity and organ dysfunction. Standardized rates of sepsis increased over time, with an annual change of 4.7 (95 per cent c.i. 1.4 to 8.5) per cent, whereas the case-fatality rate declined, with an overall annual change of -3.6 (-4.3 to -2.8) per cent. The decrease in mortality was more limited in patients with organ dysfunction and in the oldest age group. Conclusion: Rates of sepsis are increasing among elderly patients undergoing surgery, whereas in-hospital case fatality, although common, is showing a decreasing trend.