PURPOSE: ICD-9-CM diagnosis code 995.92 for severe sepsis (SIRS due to infectious process with organ dysfunction) became available in October 2002, but its adoption to date has been limited. We compared the number, characteristics, and outcomes of patients believed to have severe sepsis (SS) against patients coded with 995.92.
METHODS: We conducted a retrospective analysis of 2002-2004 discharge data from >400 hospitals in the Premier Perspective(TM) Comparative Database, a large U.S. clinical and economic database developed for quality and utilization benchmarking. SS patients were identified using criteria for (a) infection diagnosis or receipt of intravenous anti-infectives and (b) organ dysfunction diagnosis or receipt of organ support. We compared patients with code 995.92 to those without on the basis of patient characteristics, mortality, length of stay (LOS), and costs, using Mantel-Haenszel chi-square tests for categorical variables, Wilcoxon tests for LOS and costs, and two-sample t-tests for other continuous variables.
RESULTS: Among the 1,954,991 patients in the database, 368,698 (18.9%) had SS and 29,450 (1.5%) had code 995.92. On average, patients with code 995.92 were older (66.3 versus 64.3 years; p<0.01), had more organ dysfunctions (1.43 versus 0.96; p<0.01), and were more commonly treated in teaching hospitals (74.8% versus 72.1%; p<0.01) than other patients with SS. Patients with code 995.92 had significantly higher hospital mortality rates (44.6% versus 23.4%, p<0.01), somewhat longer hospital lengths of stay (17.4 versus 16.8 days, p<0.01), but similar total hospital costs ($40,967 versus $35,066, p = NS).
CONCLUSION: Patients who receive diagnosis code 995.92 represent a small fraction of all SS patients. This code appears to identify a subset of all severe sepsis patients with a markedly higher mortality rate but similar resource utilization.
CLINICAL IMPLICATIONS: This may be one of the first studies to examine differences between patients receiving the diagnosis code for SS and other patients with SS. Patients with ICD-9 code 995.92 should not be considered representative of all patients with SS; further research is needed to understand clinical and administrative rationale for its use.
DISCLOSURE: Frank Ernst, Shareholder Eli Lilly and Company; Employee Eli Lilly and Company.