Table 2.
Baseline Characteristics.*
| Characteristic | Colistin plus Placebo (n=213) |
Colistin plus Meropenem (n=210) |
|---|---|---|
| Demographics | ||
| Age — yr | 67.6±16.6 | 68.5±15.5 |
| Race — no. (%) | ||
| White | 108 (51) | 108 (51) |
| Asian | 89 (42) | 84 (40) |
| Other | 16 (8) | 18 (9) |
| Female — no. (%) | 83 (39) | 75 (36) |
| Region — no. (%) | ||
| Israel | 81 (38) | 85 (40) |
| Thailand | 64 (30) | 59 (28) |
| Taiwan | 26 (12) | 26 (12) |
| United States | 21 (10) | 22 (10) |
| European Union | 21 (10) | 18 (9) |
| Select comorbid conditions — no. (%) | ||
| Diabetes mellitus | 82 (39) | 85 (40) |
| Chronic lung disease | 84 (39) | 79 (38) |
| Chronic renal disease | 64 (30) | 71 (34) |
| Malignancy | 49 (23) | 50 (24) |
| Charlson Comorbidity Index score — median (IQR)† | 5 (4–7) | 5 (4–7) |
| Key patient characteristics at time of infection onset | ||
| Serum creatinine — mg/dl | 1.64±1.40 | 1.50±1.24 |
| Intensive care unit residence — no. (%) | 148 (69) | 143 (68) |
| Mechanical ventilation — no. (%) | 132 (62) | 120 (57) |
| APACHE II score — median (IQR)‡ | 22 (17–26) | 21 (17–26) |
| Vasopressor use — no. (%) | 30 (14) | 30 (14) |
| Infection characteristics — no. (%) | ||
| Infection type | ||
| Pneumonia | 152 (71) | 146 (70) |
| With secondary bacteremia | 10 (5) | 13 (6) |
| Bloodstream infection | 61 (29) | 64 (30) |
| Infecting organism | ||
| Acinetobacter baumannii∫ | 165 (77) | 164 (78) |
| Enterobacterales | 34 (16) | 35 (17) |
| Pseudomonas aeruginosa | 23 (11) | 20 (10) |
Plus–minus values are means±SD. APACHE II denotes Acute Physiology and Chronic Health Evaluation II; and IQR, interquartile range.
Charlson Comorbidity Index scores range from 0 to 41, with higher scores representing a lower estimated 10-year survival rate. A score of 5 represents an estimated 10-year survival rate of 21%.
APACHE II scores range from 0 to 71; a score of 20 to 24 has an estimated mortality of 40%, whereas an APACHE II score of 25 is associated with a predicted in-hospital mortality of 55%. APACHE II was only assessed in those with pneumonia in the intensive care unit at the time of enrollment.
This included two non–extensively drug-resistant A. baumannii isolates susceptible to ampicillin/sulbactam, in which the patient had a penicillin allergy contraindicating ampicillin/sulbactam.