Spotentially eligible patients identified from the Infection Prevention and Control reports were not included because they had undergone cancer chemotherapy in the preceding 8 weeks. The case patients were then matched to controls according to the previously stated criteria. Eight case patients were excluded at this stage because matched controls could not be found: 4 cases were unmatched for hospital unit, 3 for age, and 1 for month of hospital admission. Therefore, 142 cases and 142 controls were included in the analysis (Table 1). One case patient had a recurrent infection with an interval longer than 2 months between the original and recurrent infections; this patient was included as 2 separate cases, with different matched controls. In the statistical analysis, the number of potential variables in the model increased from 9 to 15; however, we were still within the limit of 5 to 10 observations per model parameter recommended by Stokes and others. Nonetheless, all of the Wald test p values for the parameters of these variables were nonsignificant, the smallest being 0.29. generic cialis 20mg
There was no correlation between current use of PPIs and development of CDAD (OR 1.0, 95% CI 0.99-1.01). Diabetes, use of enteral feeding, gastrointestinal surgery, and previous residence or care in an institution did not meet the initial significance criteria (p < 0.10) for inclusion in the statistical analysis. Cancer and inflammatory bowel disease did meet the initial significance criteria but did not demonstrate a positive correlation with development of CDAD. Past use of PPIs and use of antibiotics were associated with the development of CDAD. The past use of PPIs was associated with CDAD (OR 2.4, 95% CI 1.4-4.3), whereas the use of antibiotics was highly associated with the CDAD outbreak (OR 12.0, 95% CI 4.0-35.7). Specifically, fluoroquinolones and cephalosporins were most widely used among case patients.
Table 1. Baseline Characteristics of Cases and Controls
As discussed above, multiple risk factors have been established in the development of CDAD. Therefore, potential associations between risk factors were analyzed to determine if they influenced one another. Case patients seemed more likely than controls to have had 3 contributing risk factors (Figure 1). However, the statistical analysis for interactions, as described in the Methods section, suggested no interactions between risk factors. viagra 50 mg
Figure 1. Distribution of patients according to number of risk factors.