Nosocomial Clostridium difficile Infection Increasingly Common, Study Shows

   The incidence of Clostridium difficile infections (CDI) declined from 2005 to 2006 while case mortality and colectomy continue to rise, according to data presented at the 50th Interscience Conference on Antimicrobial Agents and Chemotherapy in Boston. Cory Fominaya, MD, and colleagues at the State University of New York at Buffalo performed the research.

   They used the Nationwide Inpatient Sample of approximately 84 million discharges to identify patients discharged with a diagnosis of CDI during the years 2003-2006. The cases were analyzed descriptively for age, gender, race, LOS, mortality, total colectomy, Charlson comorbidity index (CCI), and payer information. The test of trend was used to evaluate trends in CDI discharges, associated mortality, and colectomy.

   During the study period, the rate of CDI-associated discharges increased from 518 to 792 cases per 100,000 discharges P=0.01). In 2005, case mortality peaked at 983 deaths per 100,000 diagnoses with a reversal of trend in 2006 to 930 deaths per 100,000 (P<0.01). Case mortality was predicted by several patient factors including female gender (odds ratio [OR] 0.84, 95% confidence interval [CI], 0.82 to 0.87), Native American (OR 1.44, 95% CI, 1.03 to 2.01), and African American ethnicity (OR 1.06,  95% CI, 1.00 to 1.12), Medicare (OR 0.69, 95% CI, 0.65 to 0.73), privately insured  (OR 1.18, 95% CI, 1.09 to 1.28), and other payer (OR 0.85, 95% CI, 0.73 to 0.99), and CCI >1 (adjusted odds ratio 1.69, 95% CI, 1.62 to 1.75).

   According to Dr. Fominaya, during the study period the rate of colectomy increased from 0.36 per 100 cases to 0.43 per 100 cases (P=0.001). In multivariate analysis,  CDI-associated colectomy was predicted by age (OR 1.01, 95% CI, 1.01 to 1.02), later year of diagnosis (OR 0.89, 95% CI, 0.83 to 0.96), white ethnicity (OR 0.61, 95% CI,  0.49 to 0.78), and CCI >3 (OR 2.54, 95% CI, 1.92 to 3.35).

   Overall, the data suggest that CDI continues to be an increasingly common event in community hospitals, despite a downward trend late in the study period. And the results show a strong association between colectomy and mortality.