Medication Exposure and Risk of Recurrent Clostridium difficile Infection in Community-Dwelling Older People and Nursing Home Residents.

BACKGROUND/OBJECTIVES: It is unclear how medication exposures differ in their association with recurrent Clostridium difficile infection (rCDI) in elderly nursing home (NH) residents and community-dwelling individuals. This study examined these exposures to determine whether the risk of rCDI differs according to living environment.

DESIGN: Retrospective.

SETTING: Academic and community healthcare settings.

PARTICIPANTS: Individuals aged 65 and older with CDI (N = 616).

MEASUREMENTS: Information on participant characteristics and medications was extracted from the electronic medical record (EMR). We used separate extended Cox models according to living environment to identify the association between medication use and risk of rCDI.

RESULTS: Of the 616 elderly adults treated for CDI, 24.1% of those living in the community and 28.1% of NH residents experienced recurrence within 1 year. For community-dwelling participants, the risk of rCDI was 1.6 times as high with antibiotic exposure and 2.5 times as high with acid-reducing medication exposure, but corticosteroid exposure was associated with a 39% lower risk of recurrence. For NH residents, the risk of rCDI was 2.9 times as high with acid-reducing medication exposure and 5.9 times as high with corticosteroid medication exposure. Antibiotic exposure was associated with an increased risk of recurrence only in community-dwelling participants (adjusted hazard ratio = 1.63, 95% confidence interval = 1.00-2.67).

CONCLUSION: Risk of rCDI is greater with acid-reducing medication use than antibiotic use after initial CDI treatment, although the risk varied depending on living environment. Corticosteroid use is associated with greater risk of recurrence in NH residents but lower risk in community-dwelling elderly adults.