While the hospitalization costs of severe sepsis have been estimated, the long-term economic consequences of sepsis survivors may be of greater importance to healthcare decision-makers. OBJECTIVES: The objective of this study is to estimate and compare the long-term healthcare cost for patients following discharge from a hospitalization for sepsis or severe sepsis. METHODS: This retrospective database study used managed care claims data from 1995 to 1998 to identify patients greater than 18 years of age with an ICD-9 code indicating septicemia or bacteremia during a hospitalization. Patients who experienced any signs of organ failure during the index hospitalization as indicated by ICD-9 codes comprised the severe sepsis group; the remaining patients comprised the sepsis group. The index hospitalization was defined as the hospitalization containing the first sepsis or severe sepsis diagnosis during the above timeframe. Patients were excluded if they did not have any claims following hospital discharge. Log-transformed monthly healthcare expenditures were analyzed using analysis of variance. The propensity score method using 5 subclassifications was used to make both groups (sepsis and severe sepsis) comparable, reducing the bias in the analysis. RESULTS: Of approximately 3 million members in the database, 3403 patients met the inclusion criteria with 2666 (78.3%) in the sepsis group and 737 (21.7%) in the severe sepsis group. The adjusted mean monthly cost after discharge from the index hospitalization was $496.63 (95%CI: $466.23 - $529.01) for the sepsis group and $571.29 (95%CI: $506.87 - $643.89) for the severe sepsis group. Severe sepsis patients were 15.0% (p=0.043) more costly than the sepsis patients. CONCLUSION: Interventions aimed at reducing the likelihood of disease progression from sepsis to severe sepsis are likely to have beneficial long-term economic consequences for patients and healthcare systems.