Inpatient Expenditures Attributable to Hospital-Onset Clostridium difficile Infection: A Nationwide Case–Control Study in Japan

Background: Hospital-onset Clostridium difficile infections (CDIs) have a considerable clinical and economic impact on patients and payers. Quantifying the economic impact of CDIs can guide treatment strategies. However, previous studies have generally focused on acute care hospitals, and few have included cost estimates from non-acute care hospitals such as long-term care facilities. Aim: This study aimed to quantify the hospital-onset CDI-attributable inpatient expenditures and length-of-stay durations in all healthcare institutions that provide inpatient care (including acute and non-acute care) in Japan. Methods: Using national-level insurance claims data, we analyzed patients who had been hospitalized between April 2010 and December 2016. CDI cases were identified and matched with non-CDI controls using hospitalization year, treating hospital, age, sex, surgical procedure, comorbidities, and main diagnoses. Through multivariable regression analyses, we estimated the CDI-attributable inpatient expenditures (2016 US dollars) and length-of-stay durations (days) while adjusting for variations in factors such as patient characteristics, comorbidities, surgery, prescribed antibiotic, geographic region, and hospitalization year. We also analyzed the CDI-attributable inpatient expenditures and length-of-stay durations according to hospital type (acute care and rehabilitation/long-term care). Results: The analysis was conducted using 3768 matched pairs. Overall, CDI-attributable inpatient expenditures and length-of-stay durations were US$3213 and 11.96 days, respectively. Rehabilitation/long-term care hospitals had substantially higher inpatient expenditures and longer hospitalizations than acute care hospitals. Conclusion: This study quantified the hospital-onset CDI-attributable inpatient expenditures and hospitalizations in both acute and non-acute care hospitals. The inclusion of non-acute care hospitals provides a more accurate representation of the economic burden of CDIs.