Economic and Disease Burden Associated with Invasive Escherichia coli Disease in the United States

Invasive Escherichia coli disease (IED) incidence has increased over recent years among aging populations and has rising antimicrobial resistance. Here, we report on a comparative, cross-sectional, retrospective analysis of US patients with IED to quantify IED-related healthcare resource utilization (HCRU), costs, and impact on health-related quality of life (HRQoL). This study included Kaiser Permanente Northwest (KPNW) members aged ≥ 60 years enrolled between July 2019 and January 2020. Patients were divided into three groups: Group 1 had experienced a recent IED episode (≤ 3 weeks before enrollment); Group 2 had experienced a former IED episode (13–18 months before enrollment); Group 3 was at risk with no prior history of IED. Data were collected from electronic hospital records, a patient survey, and the EuroQol 5-Dimension 5-Level (EQ-5D-5L) questionnaire. Mean costs were adjusted according to individual follow-up. Patient characteristics were generally consistent across Groups 1 (n = 289), 2 (n = 319), and 3 (n = 340). Inpatient hospitalization was observed in 84%, 44%, and 15% of patients in Groups 1, 2 and 3, respectively. Mean direct costs per patient (per 30-day follow-up) were $17,168, $2530, and $1094 in Groups 1, 2, and 3, respectively. Mean total costs per patient in the year following an IED episode (Group 2) were $35,034 vs. $16,163 in the at-risk Group 3. HRQoL was poor for patients with recent IED, with a mean EQ-5D-5L utility index value of 0.25 on the worst day of illness. During a 12-month follow-up period, rehospitalization rates and mean number of antibiotic prescriptions were ~ threefold higher for patients who recovered from IED vs. those at risk. These data demonstrate substantial short- and long-term impacts of IED on HCRU, IED-related costs, and HRQoL. Additional research is needed to further value the impact of novel IED prevention strategies.