Burden of Clostridium difficile-associated disease among patients residing in nursing homes: a population-based cohort study.

BACKGROUND: Clostridium difficile (C. difficile) infection (CDI) is the leading cause of nosocomial diarrhea in the United States. This study aimed to examine the incidence of CDI and evaluate mortality and economic burden of CDI in an elderly population who reside in nursing homes (NHs).

METHODS: This was a population-based retrospective cohort study focusing on US NHs by linking Medicare 5% sample, Medicaid, Minimum Data Set (MDS) (2008-10). NH residents aged ≥65 years with continuous enrollment in Medicare and/or Medicaid Fee-for-Service plan for ≥12 months and ≥2 quarterly MDS assessments were eligible for the study. The incidence rate was calculated as the number of CDI episodes by 100,000 person-years. A 1:4 propensity score matched sample of cohorts with and without CDI was generated to assess mortality and health care costs following the first CDI.

RESULTS: Among 32,807 NH residents, 941 residents had ≥1 episode of CDI in 2009, with an incidence of 3359.9 per 100,000 person-years. About 30% CDI episodes occurred in the hospital setting. NH residents with CDI (vs without CDI) were more likely to have congestive heart failure, renal disease, cerebrovascular disease, hospitalizations, and outpatient antibiotic use. During the follow-up period, the 30-day (14.7% vs 4.3%, P < 0.001), 60-day (22.7% vs 7.5%, P < 0.001), 6-month (36.3% vs 18.3%, P < 0.001), and 1-year mortality rates (48.2% vs 31.1%, P < 0.001) were significantly higher among the CDI residents vs non-CDI residents. Total health care costs within 2 months following the first CDI episode were also significantly higher for CDI residents ($28,621 vs $13,644, P < 0.001).

CONCLUSIONS: CDI presents a serious public health issue in NHs. Mortality, health care utilization, and associated costs were significant following incident CDI episodes.