Association of Household Pets, Common Dietary Factors, and Lifestyle Factors with Clostridium difficile Infection.

Background: Clostridium difficile infection (CDI) is one of the most common hospital-acquired infections and is associated with significant morbidity and mortality. Since owning a cat or dog could enrich the gut microbiome, we hypothesized that it would be protective against CDI.

Aims: We conducted a survey study on patients tested for CDI in order to assess whether living in the presence of a pet is associated with a decreased risk of CDI.

Methods: We surveyed subjects aged 18-90 over a 14-month period using a retrospective case-control design. Subjects with CDI were matched by gender and age to patients who tested negative and had no prior history of CDI. A web-based survey was provided to subjects by mail or assisted by phone. Conditional logistic regression was used to assess for associations between CDI and the various risk factors.

Results: 205 CDI positive and 205 CDI negative subjects (response rate of 50.2%) were included. After matching for age and sex, living with a cat or dog was not associated with negative CDI testing. Exploratory multivariable modeling identified an unexpected association between positive CDI testing and high meat intake (OR 2.13, 95% CI 1.21-3.77) as well as between positive CDI testing and cat allergies (OR 1.88, 95% CI 1.02-3.46).

Conclusion: Living with a cat or dog was not associated with negative CDI testing. Several novel risk factors for CDI have been identified including high meat intake and cat allergies.