LAUSR

Critical Care Medicine www.ccmjournal.org 2043 The newest article by Paoli et al (1), published in this issue of Critical Care Medicine, adds to the body of literature on sepsis epidemiology using the increasingly available pool of large clinical and administrative databases to characterize the financial burden of sepsis in the United States. This particular study (1) uses data from Premier, Inc (Charlotte, NC), a U.S. healthcare improvement company that provides analytics and other services to its hospital alliance members (2). The 2010–2016 data in the study by Paoli et al (1) represent an approximately 20% nonrandom sample of U.S. hospitalizations, capturing greater than 2.5 million sepsis hospitalizations using a combination of International Classification of Diseases, 9th Edition, International Classification of Diseases, 10th Edition, and Diagnosis-Related Group (DRG) case-finding definitions. These recent data demonstrate important, recurrent themes in sepsis epidemiology: sepsis disproportionately affects older adults (mean age, 65 yr), sepsis is predominantly community acquired (87%), sepsis is expensive (mean hospital costs $21,500), and sepsis is associated with high hospital mortality (one in eight patients) and high rates of 30-day readmission for survivors (one in eight patients). Importantly, there are two axes along which the investigators add novel information to the field of sepsis epidemiology: comparisons of “aggregate” costs by sepsis severity and comparisons of sepsis outcomes and resource utilization by “present on admission” (POA) status. The investigators analyze their data by sepsis severity, using administrative coding that is consistent with the sepsis, severe sepsis, and septic shock classifications in existence before Sepsis-3 (3). The finding that increasing sepsis severity is associated with increasingly worse outcomes and higher costs is intuitively correct and a check on internal validity and is expanded with provocative assertions regarding the societal burden of sepsis under its earlier clinical definitions. Although sepsis without organ dysfunction was associated with shorter length of stay, lower costs, and lower hospital mortality than more severe forms of sepsis, given that it accounted for 55% of the sepsis cases, it accounted for the highest aggregated cost and hospital bed utilization. This highlights an important aspect of the evolution to the Sepsis-3 definition where sepsis requires organ dysfunction, and less ill patients are simply “infected,” and in the process altering the epidemiologic estimates of “sepsis” and challenging epidemiologists, providers, and policy makers to translate across the definitional, clinical, and administrative categorizations. Before delving into the analyses of sepsis by POA status, background on the creation of POA indicators is important. These indicators arose from the 2005 Deficit Reduction Act, which called for the ongoing identification of conditions that are “high cost or high volume or both, result in the assignment of a case to a DRG that has a higher payment when present as a secondary diagnosis and could reasonably have been prevented through the application of evidence-based guidelines” (4). The intent of the regulation was to encourage hospitals to avoid these conditions by not reimbursing for hospital-acquired (i.e., not POA) conditions that may have been preventable. Since its operationalization in 2008, the Centers for Medicare and Medicaid Services (CMS) has not paid hospitals for the costs associated with these conditions when they are included among the secondary diagnoses of the discharge record without a POA designation. CMS requires hospitals to record POA indicators on all hospital discharge diagnoses, and although sepsis is not explicitly on this list, six of the 14 categories of hospital-acquired conditions are related to sepsis, such as catheterassociated urinary tract infections, vascular catheter-associated infections, and surgical site infections (5). An important caveat to the POA system acknowledged by the authors is that POA *See also p. 1889.