TABLE 1.
Descriptive characteristics of cohort and univariate analysis
| Variablea | Entire cohort (n = 2,788) | Patients on piperacillin- tazobactam (n = 447) | Patients on broad- spectrum cephalosporin (n = 2,341) | P |
|---|---|---|---|---|
| Demographics | ||||
| Mean age (yr) ± SD | 62.5 ± 16.3 | 62.0 ± 15.3 | 62.6 ± 16.5 | 0.52 |
| No. of males (%) | 1,174 (42) | 145 (32) | 1,029 (44) | <0.001 |
| Comorbidities (n [%]) | ||||
| Cardiovascular disease | 1,995 (72) | 344 (77) | 1,651 (71) | 0.006 |
| Diabetes mellitus | 1,305 (47) | 294 (66) | 1,011 (43) | <0.001 |
| Malignancy | 438 (16) | 53 (12) | 385 (16) | 0.015 |
| Liver disease | 320 (11) | 45 (10) | 275 (12) | 0.31 |
| Renal disease | 419 (15) | 72 (16) | 347 (15) | 0.49 |
| Lung disease | 452 (16) | 46 (10) | 406 (17) | <0.001 |
| AIDS | 166 (6) | 14 (3) | 152 (6) | 0.006 |
| Organ transplant | 142 (5) | 34 (8) | 108 (5) | 0.008 |
| Hospital exposures | ||||
| Median length of hospital stay (days) before entry into cohort (interquartile range) | 1 (0-4) | 1 (0-4) | 1 (0-4) | 0.36 |
| Median no. of days in cohort (interquartile range) | 6 (3-11) | 7 (4-13) | 6 (3-11) | 0.007 |
| No. of transfers (%) from other institutions | 806 (29) | 137 (31) | 669 (29) | 0.38 |
| Intensive care unit stay (n [%]) | 995 (36) | 111 (25%) | 884 (38) | <0.001 |
| Surgical procedure (n [%]) | 798 (29) | 183 (41%) | 615 (26) | <0.001 |
| Exposure to other antibiotics (n [%]) | ||||
| Aminoglycosides | 409 (15) | 63 (14) | 346 (15) | 0.71 |
| Fluoroquinolones | 373 (13) | 69 (15) | 304 (13) | 0.16 |
| Resistant Enterobacter (n [%]) | 62 (2) | 11 (2) | 51 (2) | 0.71 |
a
n = number of isolates.