Epidemiology of sepsis in Korea: a population-based study of incidence, mortality, cost and risk factors for death in sepsis

Objective To investigate the epidemiology of sepsis in Korea and identify risk factors for death in sepsis. Methods We conducted a longitudinal, population-based epidemiological study of sepsis in Korea from 2005 to 2012 using the National Health Insurance Service-National Sample Cohort, a population-based cohort representing 2.2% of the Korean population. The primary objective was to assess the incidence, mortality and cost of sepsis. The secondary objective was to identify the risk factors for death in sepsis. Claim records of admitted adult patients (aged >= 15 years) were analyzed. Sepsis was defined as 1) bacterial or fungal infection or the conditions they often complicate, 2) prescription of intravenous antibiotics, and 3) presence of any organ dysfunction. Comorbidities were defined using the Charlson/Deyo method. Risk factors for 6-month mortality were assessed using multivariable logistic regression. Results A total of 22,882 cases were identified. Both incidence and 6-month mortality increased from 265.7 (95% confidence interval [CI), 254.7 to 277.1) to 453.1 (95% CI, 439.0 to 467.5) per 100,000 person-years (P-trend <0.001) and from 26.5% (95% CI, 24.4% to 28.8%) to 30.1% (95% CI, 28.4% to 31.9%), respectively. After standardization, the increasing trend of incidence was slower but still significant (P-trend <0.001), while that for mortality was not (P-trend 0.883). The average cost increased by 75.5% (P-trend <0.001). Multivariable logistic regression identified various risk factors for mortality. Conclusion The burden of sepsis in Korea was high and is expected to increase considering the aging population. Proactive measures to curtail this increase should be sought and implemented.