Epidemiology of severe sepsis in Japanese intensive care units: a prospective multicenter study

Severe sepsis is a leading cause of morbidity and mortality in the intensive care unit (ICU). We conducted a prospective multicenter study to evaluate epidemiology and outcome of severe sepsis in Japanese ICUs. The patients were registered at 15 general critical care centers in Japanese tertiary care hospitals when diagnosed as having severe sepsis. Of 14,417 patients, 624 (4.3%) were diagnosed with severe sepsis. Demographic and clinical characteristics at enrollment (Day 1), physiologic and blood variables on Days 1 and 4, and mortality were evaluated. Mean age was 69.0 years, and initial mean Acute Physiology and Chronic Health Evaluation (APACHE) II and Sequential Organ Failure Assessment (SOFA) scores were 23.4 and 8.6, respectively. The 28-day mortality was 23.1%, and overall hospital mortality was 29.5%. SOFA score and disseminated intravascular coagulation (DIC) score were consistently higher in nonsurvivors than survivors on Days 1 and 4. SOFA score, DIC score on Days 1 and 4, and hospital mortality were higher in patients with than without septic shock. SOFA score on Days 1 and 4 and hospital mortality were higher in patients with than without DIC. Logistic regression analyses showed age, presence of septic shock, DIC, and cardiovascular dysfunction at enrollment to be predictors of 28-day mortality and presence of comorbidity to be an additional predictor of hospital mortality. Presence of septic shock or DIC resulted in approximately twice the mortality of patients without each factor, whereas the presence of comorbidity may be a significant predictor of delayed mortality in severe sepsis.