Table 3. The effect of antibiotic treatment as risk factor for vancomycin-resistant enterococci.
| Cases (%) | Control (%) | Unadjusted effect | Adjusted for explanatory modela | Adjusted for model and other antibioticsa | ||||
|---|---|---|---|---|---|---|---|---|
| Antibiotic agent |
(233) |
(647) |
OR |
p
value |
OR
(95% CI) |
p
value |
OR
(95% CI) |
p
value |
| Penicillins | 67 (29) | 134 (21) | 1.5 | 0.04 | .99 (.63 to 1.6) | 0.97 | 1.0 (.64 to 1.7) | 0.86 |
| β-lactam-inhibitor combination | 49 (21) | 98 (15) | 1.5 | 0.07 | .94 (.6 to 1.5) | 0.78 | ||
| Cephalosporins | 104 (45) | 248 (38) | 1.2 | 0.28 | 1.5 (1.0 to 2.4) | 0.048 | ||
| Third generation | 69 (30) | 97 (15) | 2.6 | <0.001 | 2.8 (1.7 to 4.5) | <0.001 | 2.8 (1.7 to 4.8) | <0.001 |
| Vancomycin (p.o.) | 4 (1.7) | 7 (1.1) | 1.2 | 083 | 1.0 (.25 to 4.2) | 0.96 | ||
| Vancomycin (i.v.) | 67 (29) | 121 (19) | 1.7 | 0.016 | 1.4 (.89 to 2.3) | 0.19 | .99 (.57 to 1.7) | 0.98 |
| Metronidazole (p.o.) | 13 (5.6) | 23 (3.6) | 1.5 | 0.29 | 1.0 (.42 to 2.5) | 0.97 | ||
| Metronidazole (i.v.) | 47 (20) | 57 (9) | 2.5 | <0.001 | 2.3 (1.3 to 3.9) | 0.003 | 2.1 (1.2 to 3.7) | 0.008 |
| Clindamycin | 20 (8.6) | 51 (7.9) | 1 | 0.9 | 1.5 (.76 to 2.8) | 0.26 | 1.1 (.55 to 2.3) | 0.76 |
| Quinoloneb | 48 (21) | 68 (11) | 2 | 0.005 | 1.6 (.94 to 2.6) | 0.086 | 1.5 (.85 to 2.6)b | 0.17b |
| Imipenem | 19 (8.2) | 27 (4.2) | 1.7 | 0.12 | 1.3 (.61 to 2.9) | 0.47 | 1.2 (.52 to 2.8) | 0.66 |
aAdjusted for the explanatory model detailed in Table 2. b When included as a continuous variable (number of days of treatment with quinolone) OR=1.03, p=0.05. OR, odds ratio; p.o., orally; i.v., intravenously.