Incidence, healthcare and out-of-pocket costs, and mortality of Clostridioides difficile infection among US adults aged 18 to 64 years

Abstract

Objective: To estimate incidence and healthcare costs and mortality associated with Clostridioides difficile infection (CDI) among adults <65 years old. Design: Retrospective cohort study. Patients: First CDI episodes among commercially insured US patients 18–64 years old were identified from a large claims database. CDI+ patients were propensity score−matched (PSM) 1:1 with CDI− controls using clinically relevant variables including comorbidities. Methods: Annual CDI incidence was calculated by age group and year (2015−2019). Healthcare utilization, costs, and mortality were analyzed by age group, acquisition (healthcare and community), and hospitalization status by calculating CDI-excess costs and mortality as the difference between PSM CDI+ and CDI− individuals. Results: In 50–64- and 18–49-year-olds, respective CDI incidence per 100,000 person-years decreased from 217 and 113 cases in 2015 to 167 and 87 cases in 2019. Most cases (76.5%–86.9%) were community-associated. The costs and mortality analyses included 6,332 matched CDI+/− 50–64-year-olds and 6,667 CDI+/− 18–49-year-olds. Among 50–64-year-olds, mean 2-month healthcare and patients’ out-of-pocket costs were $11,634 and $573 higher, respectively, in the CDI+ versus CDI− group. Among 18–49-year-olds, 2-month costs were $7,826 and $642 higher. Healthcare costs were higher for healthcare- versus community-associated CDI. At the 12-month follow-up, mortality was significantly higher in the CDI+ versus CDI− groups for both 50–64-year-olds (4.2% vs 2.0%; P < .001) and 18–49-year-olds (1.2% vs 0.6%; P < .001). Mortality rates were higher for hospitalized versus nonhospitalized CDI+ patients. Conclusions: Prevention of CDI among adults 18–64 years old may significantly reduce costs and mortality.