OBJECTIVES:

Elderly cancer patients represent a population that is vulnerable for Clostridium difficile infection (CDI). Frequent hospitalizations, and the chemotherapy treatment have been identified as factors associated with the development of CDI. The objective of this study was to identify the patterns and determinants of CDI in a nationwide sample of elderly patients.

METHODS: We used NCI’s Surveillance, Epidemiology, and End Results registry linked Medicare (SEER-Medicare) 2007-2012 files. We included patients’ aged ≥65 year, with diagnosis of lung/breast/ovarian/colorectal/prostate cancer, or lymphoma/multiple myeloma/leukemia during 2008-2011. We excluded those with non-continuous Medicare enrollment, or HMO enrollment. Incidence of CDI was determined by identifying any claim with primary/secondary diagnosis of CDI during the one year follow-up period following diagnosis. Recurrent CDI was identified by presence of any claim that was >2 weeks and ≤8 weeks from the index CDI diagnosis date. Covariates including antibodies/proton pump inhibitors usage were captured and included in the analysis. Chi-square tests, and hierarchical generalized logistic models were conducted to identify determinants of CDI.

RESULTS:

We identified 41,470 elderly patients with lung/breast/ovarian/colorectal/prostate cancer, or lymphoma/multiple myeloma/leukemia diagnosis during the study years. While few (393) patients developed CDI within one year of diagnosis, more than 50% (197) of those patients developed recurrent CDI. Patient characteristics were not associated with risk of developing CDI, however, significant differences were observed in antibiotics/proton pump inhibitors exposure across all cancer types (p<0.001).

CONCLUSIONS:

While the incidence of CDI is lower among cancer patients, the rate of recurrent CDI was significantly higher. Strategies to prevent CDI recurrence in this population are therefore warranted.