Date of Award

January 2015

Document Type

Open Access Thesis

Degree Name

Master of Public Health (MPH)


School of Public Health

First Advisor

Jim Hadler

Second Advisor

Dan Weinberger


INTRODUCTION: Clostridium difficile infection (CDI), initially thought to be acquired in the hospital, has occurred often in persons not recently hospitalized. Community-associated CDI (CA-CDI) may affect healthy individuals who lack the traditional risk factors for health care-associated CDI (HA-CDI). Risk factors for CA-CDI have yet to be fully identified.

OBJECTIVES: The objective of this study was to assess the risk factors for CA-CDI in the small Connecticut sample of a larger multi-state case-control study being conducted by the Emerging Infections Programs, and to help inform analysis of the larger study.

METHODS: A matched case-control study was conducted of consenting individuals. Cases had positive cultures for C. difficile and underwent chart review to confirm as community-associated. Controls were persons identified through random digit dialing without prior CDI and were age and county-matched to cases. Participants were enrolled from November 2014 through March 2015. Interview questions were asked regarding potential exposures in the preceding 2-12 weeks. Matched and conditional logistic regression analyses were conducted. An unmatched analysis was performed to stratify leading C. difficile exposures by antibiotic use.

RESULTS: Of the cases, 16 (72.3%) reported exposure to a medical setting within two weeks of symptom onset. Nine (56.3%) of these reported having taken an antibiotic within four weeks of symptom onset. In the matched analysis, exposures in the twelve weeks prior to symptom onset significantly increasing the odds of CA-CDI included antibiotic use (OR=12.00, 95% CI 1.78-512.97), any medical/dental procedure (OR=10.00, 95% CI 1.42-433.98), any medical care/visit (OR=9.61, 95% CI 1.87-undefined), and use of untreated tap water (OR=3.50, McNemar’s). In the unmatched analysis, those who did not take antibiotics and had a household member who wore diapers had a significantly increased odds of CA-CDI (OR=116.67, 95% CI 1.22-5.88).

CONCLUSION: Common risk factors for CA-CDI included exposure to a health care facility, having a medical/dental procedure, and taking an antibiotic in the twelve weeks prior to symptom onset. Antibiotics taken in proximity to time of exposures appear to facilitate them. Significant exposures should be further investigated in the larger study. While the small sample size (N=42) of this study limited the statistical power, the analysis provides a preview of what may be seen in the results of the larger multi-state study to which this sample contributes.


This is an Open Access Thesis.

Open Access

This Article is Open Access