Lung Cancer Chemotherapy-Associated Clostridium Difficile Infection Among Elderly Patients in the United States

OBJECTIVES: Elderly cancer patients comprise a population that is vulnerable for Clostridium difficile infection (CDI). In addition to the hospitalizations, the administration of chemotherapeutic agents has been associated with the development of CDI. The objective of this study was to identify the patterns of chemotherapy-associated CDI (Chemo-CDI), in a nationwide sample of elderly lung cancer patients.

METHODS: We used National Cancer Institute’s Surveillance, Epidemiology, and End Results registry linked Medicare (SEER-Medicare) 2007-2012 files. We included patients’ aged ≥65 year, with lung cancer diagnosis during 2008-2011. We excluded those not receiving chemotherapy, with non-continuous Medicare enrollment/HMO enrollment. Chemotherapy receipt was identified using appropriate ICD-9/HCPCS/CPT codes. Incidence of CDI following chemotherapy were determined by identifying any claim with primary/secondary diagnosis of CDI during the 2-month follow-up period.

RESULTS: We identified 168,212 elderly patients with lung cancer diagnosis during the study years. Of those, 5,770 patients were included in the study based on the inclusion criteria. While only few (38) patients developed Chemo-CDI within one year of diagnosis, almost 50% of those patients developed recurrent Chemo-CDI. Patient characteristics were not associated with risk of developing Chemo-CDI, however, significant differences were observed in antibiotics exposure (p<0.001).

CONCLUSIONS: While incidence of Chemo-CDI is lower among lung patients receiving chemotherapy, the rate of recurrent Chemo-CDI was higher. Strategies to prevent CDI recurrence in this population are therefore warranted.