Rising Economic Impact of Clostridium difficile-Associated Disease in Adult Hospitalized Patient Population

Abstract

Background.Clostridium difficile-associated disease (CDAD) is responsible for increased morbidity and a substantial economic burden. Incidences of CDAD, including those with a severe course of illness, have been increasing rapidly.Objective.To evaluate the excess mortality, increased length of stay (LOS) in the hospital, and additional costs associated with CDAD.Design.A retrospective matched cohort study.Patients.Adult patients admitted to a large tertiary care hospital between January 2000 and October 2005.Methods.Adult patients were tested with a C. difficile laboratory assay at admission or 72 hours after admission. Infected patients had lor more positive assay results and were individually matched to 1 uninfected patient who had negative assay results, by exposure time, age, ward, and at least 2 measurements for comorbidity and severity of illness.Results.The incidence rate of CDAD among adult patients increased from 0.57 cases per 1,000 patient-days at risk before 2004 to 0.88 cases per 1,000 patient-days at risk after 2004 (P < .001). The 630 infected patients had a mortality rate of 11.9%; the 630 uninfected patients had a mortality rate of 15.1% (P = .02). After adjustment in the multivariate analysis, we found that the LOS for infected patients was 4 days longer than that for uninfected patients (P < .001). If CDAD occurred after 2004, the additional LOS increased to 5.5 days. The direct cost associated with CDAD was $306 per case; after year 2004, it increased to $6,326 per case.Conclusions.There may be no excess mortality among patients with CDAD, compared with patients without it, but the economic burden of CDAD is increasing. By 2004, CDAD-associated medical expenditures approached $1,000,000 per year at our institution alone.