Table 1 Comparison of clinical characteristics and outcomes between patients receiving combination therapy and monotherapy
Variable | Total (n = 307) | Combination therapy (n = 171) | Monotherapy (n = 136) | P-value |
|---|---|---|---|---|
Age (years, median, IQR) | 65.0 (53.0, 75.0) | 68.0 (56.0, 78.0) | 61.0 (49.0, 72.0) | 0.001 |
Male (n, %) | 232 (75.6) | 130 (76.0) | 102 (75.0) | 0.866 |
BMI (kg/m2, mean ± SD) | 23.4 ± 8.4 | 22.9 ± 2.6 | 24.7 ± 12.2 | 0.132 |
Participating hospital | ||||
 1 | 105 (34.2) | 65 (38.0) | 40 (29.4) | 0.115 |
 2 | 81 (26.4) | 46 (26.9) | 35 (25.7) | 0.818 |
 3 | 54 (17.6) | 28 (16.4) | 26 (19.1) | 0.531 |
 4 | 67 (21.8) | 32 (18.7) | 35 (25.7) | 0.139 |
Comorbidities (n, %) | ||||
 Cardiovascular disease | 176 (57.3) | 104 (60.8) | 72 (52.9) | 0.166 |
 Diabetes mellitus | 113 (36.8) | 74 (43.3) | 39 (28.7) | 0.008 |
 Cerebrovascular disease | 91 (29.6) | 60 (35.1) | 31 (22.8) | 0.019 |
 Chronic kidney disease | 55 (17.9) | 37 (21.6) | 18 (13.2) | 0.057 |
 COPD | 52 (16.9) | 31 (18.1) | 21 (15.4) | 0.533 |
 Chronic liver disease | 27 (8.8) | 15 (8.8) | 12 (8.8) | 0.987 |
 Asthma | 24 (7.8) | 13 (7.6) | 11 (8.1) | 0.875 |
 Immunocompromised status | 117 (38.1) | 77 (45.0) | 40 (29.4) | 0.005 |
Baseline clinical features and severity | ||||
 Leukocyte counts (× 109/L) | 11.1 ± 7.9 | 11.6 ± 9.5 | 10.3 ± 4.5 | 0.160 |
 PCT < 2 ng/dL (n, %) | 110 (35.8) | 61 (35.7) | 49 (36.0) | 0.948 |
 PO2/FiO2 < 300 mmHg (n, %) | 44 (14.3) | 21 (12.3) | 23 (16.9) | 0.250 |
 APACHE II score (median, IQR) | 17.0 (13.0, 22.0) | 19.0 (14.0, 23.0) | 14.0 (12.0, 19.0) |  < 0.001 |
 Coinfection (n, %) | 150 (48.9) | 91 (53.2) | 59 (43.4) | 0.087 |
 With other CRO (n, %) | 76 (24.8) | 40 (23.4) | 36 (26.5) | 0.535 |
Complications and Management | ||||
 Secondary bacteremia (n, %) | 14 (4.6) | 6 (3.5) | 8 (5.9) | 0.322 |
 Septic shock (n, %) | 55 (17.9) | 42 (24.6) | 13 (9.6) | 0.001 |
 Appropriate empirical therapy (n, %) | 37 (12.2) | 23 (13.5) | 14 (10.3) | 0.399 |
 Noninvasive mechanical ventilation (n, %) | 202 (65.8) | 116 (67.8) | 86 (63.2) | 0.399 |
 Invasive mechanical ventilation (n, %) | 155 (50.5) | 103 (60.2) | 52 (38.2) |  < 0.001 |
 Vasopressor use (n, %) | 18 (5.9) | 12 (7.0) | 6 (4.4) | 0.334 |
 ICU admission (n, %) | 233 (75.9) | 136 (79.5) | 97 (71.3) | 0.095 |
 Days from illness onset to definitive therapy (median, IQR) | 5.0 (4.0, 6.0) | 5.0 (4.0, 6.0) | 5.0 (4.0, 6.0) | 0.504 |
Outcomes | ||||
 30-day mortality | 126 (41.0) | 72 (42.1) | 54 (39.7) | 0.671 |
 30-day clinical response | 167 (54.4) | 93 (54.4) | 74 (54.4) | 0.996 |
 30-day microbiology eradiction | 131/272 (48.2) | 74/152 (48.7) | 57/120 (47.5) | 0.846 |