Medical Research: What are the main findings of the study?
Dr. Reveles: Our study utilized data from the Centers for Disease Control and Prevention’s National Hospital Discharge Surveys. Patients were selected for this study if they were at least 18 years of age and had an International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) code for Clostridium difficile infection (CDI) (ICD-9-CM code 008.45). We found that Clostridium difficile infection incidence increased from 4.5 CDI discharges/1,000 total discharges in 2001 to 8.2 CDI discharges/1,000 total discharges in 2010. Mortality varied over the study period with peak mortality occurring in 2003 (8.7%) and the lowest rate occurring in 2009 (5.6%). Median hospital length of stay (LOS) was 8 days and remained stable over the study period. In summary, the incidence of Clostridium difficile infection in U.S. hospitals nearly doubled from 2001 to 2010, with little evidence of recent decline. Additionally, there does not appear to be a significant decline in mortality or hospital LOS among patients with Clostridium difficile infection.
Medical Research: What was most surprising about the results?
Dr. Reveles: We found that in-hospital mortality among patients with primary Clostridium difficile infection is decreasing, while mortality among patients with secondary CDI is increasing. This trend is different from prior studies, which demonstrated increases in CDI-related mortality from the 1990s to the early 2000s. Because our study examined mortality through 2010, it could indicate improvements in care for patients with CDI in recent years. Increases in CDI mortality among patients with secondary CDI may indicate that mortality in these patients may be due to changes in the frequency or severity of other comorbid illnesses, though this was not specifically examined as part of our study.
Medical Research: What should clinicians and patients take away from your report?
Dr. Reveles: The incidence of Clostridium difficile infection in U.S. hospitals nearly doubled from 2001 to 2010, with little evidence of recent decline. Additionally, there does not appear to be a significant decline in mortality or hospital length of stay among patients with CDI. These data underscore the importance of directing resources to the prevention of Clostridium difficile infection, as well as developing public policy for reducing the incidence of these infections in U.S. hospitals. Judicious use of antibiotics is essential to reducing these infections, as antibiotics are the main risk factor for the development of Clostridium difficile infection. Compliance with other infection control measures, such as hand washing, is also key.
Medical Research: What recommendations do you have for future research as a result of this study?
Dr. Reveles: Further research is needed to identify factors that have led to increasing CDI rates in U.S. hospitals. Additionally, efforts are need to identify effective measures for preventing CDI and improving outcomes among patients with Clostridium difficile infection.
The rise in Clostridium difficile infection incidence among hospitalized adults in the United States: 2001-2010
Kelly R. Reveles, Grace C. Lee, Natalie K. Boyd, Christopher R. Frei. American Journal of Infection Control, 2014; 42 (10): 1028 DOI: 10.1016/j.ajic.2014.06.011