Table 1.
Patient Characteristics at ICU Admission, Comorbidities, and Therapies Used and Univariate Risk Factors for Infection
| Variable | Total (N = 774) | Available Observations | Infected (n = 359 [46%]) | Not Infected (n = 415 [54%]) | P Value | HR (95% CI) |
|---|---|---|---|---|---|---|
| Sex, female | 177 (23) | 774 (100) | 74 (21) | 103 (25) | .762 | 0.97 (0.81-1.16) |
| Age, y | 62 (54-68] | 774 (100) | 62 (54-68) | 62 (54-69) | .290 | 0.99 (0.98-1.01) |
| BMI, kg/m2 | 28 (25-31) | 713 (92) | 28 (25-31) | 28 (25-31) | .452 | 1.00 (0.99-1.02) |
| Charlson’s Comorbidity Index | 2 (1-3) | 774 (100) | 2 (1-3) | 2 (1-3) | .242 | 0.97 (0.93-1.02) |
| Immunologic comorbiditya | 91 (12) | 774 (100) | 34 (9) | 57 (14) | .027 | 0.74 (0.56-0.97) |
| Hypertension | 350 (45) | 774 (100) | 170 (47) | 180 (44) | .562 | 1.04 (0.90-1.21) |
| Diabetes | 130 (17) | 774 (100) | 57 (16) | 73 (18) | .461 | 1.08 (0.88-1.33) |
| SOFA score | 4 (3-5) | 755 (98) | 4 (3-5) | 4 (3-5) | .080 | 0.95 (0.90-1.00) |
| Nonrespiratory SOFA score | 1 (1-2) | 755 (98) | 1 (1-2) | 1 (1-2) | .027 | 0.88 (0.80-0.98) |
| SAPS II score | 37 (30-44) | 774 (100) | 38 (32-44) | 36 (30-44) | .988 | 0.99 (0.99-1.01) |
| APACHE II score | 10 (7-12) | 774 (100) | 9 (7-12) | 10 (7-13) | .867 | 1.00 (0.98-1.01) |
| Pao2 to Fio2 ratio, mm Hg | 123 (90-174) | 750 (97) | 119 (87-161) | 127 (93-182) | .337 | 0.99 (0.98-1.00) |
| Pao2 to Fio2 ratio | ||||||
| > 200b | 118 (15) | … | 46 (13) | 72 (17) | … | … |
| < 100 and ≥ 200b | 382 (49) | … | 180 (50) | 202 (49) | .626 | 0.94 (0.75-1.18) |
| ≤ 100b | 250 (32) | … | 122 (34) | 128 (31) | .602 | 0.94 (0.74-1.19) |
| Respiratory rate, beats/min | 22 (18-28) | 726 (94) | 22 (18-28) | 22 (18-27.25) | .582 | 0.99 (0.98-1.00) |
| TV/PBW, mL/kg | 6.8 (6.2-7.7) | 433 (56) | 6.9 (6.2-7.7) | 6.8 (6.1-7.8) | .397 | 1.04 (0.96-1.13) |
| PEEP, cm H2O | 12 (10-14) | 706 (91) | 12 (10-14) | 10 (10-14) | .207 | 1.02 (0.99-1.05) |
| Plateau pressure, cm H2O | 24 (22-26) | 447 (58) | 24 (22-27) | 24 (21-26) | .091 | 1.02 (0.99-1.05) |
| pH, units | 7.41 (7.34-7.46) | 755 (98) | 7.40 (7.32-7.46) | 7.42 (7.35-7.47) | .471 | 0.74 (0.32-1.68) |
| ≥ 7.35 and < 7.45 | 301 (39) | … | 137 (38) | 164 (40) | … | … |
| < 7.25c | 41 (5) | … | 25 (7) | 16 (4) | .595 | 1.08 (0.81-1.45) |
| ≥ 7.25 and < 7.35c | 188 (24) | … | 102 (28) | 86 (21) | .203 | 1.13 (0.94-1.35) |
| ≥ 7.45c | 225 (29) | … | 89 (25) | 136 (33) | .688 | 1.04 (0.86-1.26) |
| Paco2, mm Hg | 42 (36-51) | 753 (97) | 44 (36-53) | 41 (35-48) | .019 | 1.01 (1.00-1.01) |
| WBC count, 103/mm3 | 8.68 (6.24-11.7) | 762 (98) | 9.1 (6.6-12.48) | 8.38 (6.12-11.29) | .796 | 1.00 (0.99-1.01) |
| Neutrophil count, 103/mm3 | 7.26 (5.02-10.33) | 685 (88) | 7.91 (5.63-11) | 6.8 (4.81-9.78) | .127 | 1.01 (0.99-1.03) |
| Lymphocyte count, 103/mm3 | 0.7 (0.47-1) | 646 (83) | 0.7 (0.48-1) | 0.7 (0.44-1) | .491 | 0.99 (0.95-1.03) |
| Neutrophil to lymphocyte ratio | 10 (5.9-17.1) | 646 (83) | 10.6 (6-17.4) | 9.1 (5.83-16.8) | .525 | 1.00 (0.99-1.01) |
| Platelet count, 103/mm3 | 241 (180-314) | 761 (98) | 232 (179-307) | 245 (181-316) | .638 | 1.00 (0.99-1.01) |
| Serum bilirubin, mg/dL | 0.7 (0.5-1) | 739 (95) | 0.7 (0.5-1.1) | 0.7 (0.5-0.9) | .543 | 0.97 (0.88-1.07) |
| INR | 1.19 (1.1-1.29) | 513 (67) | 1.19 (1.09-1.29) | 1.18 (1.1-1.29) | .308 | 0.78 (0.48-1.26) |
| Creatinine, mg/dL | 0.86 (0.69-1.08) | 758 (98) | 0.82 (0.7-1.06) | 0.89 (0.67-1.1) | .118 | 0.92 (0.82-1.02) |
| LDH, units/L | 458 (356-600) | 657 (85) | 469 (368-597.5) | 448 (340-606.25) | .183 | 1.00 (0.99-1.01) |
| D-dimer, ng/mL | 1,201 (517-4,215) | 593 (77) | 1,663 (610-6,160) | 1,039 (447-3,013.5) | .284 | 1.00 (0.99-1.01) |
| C-reactive protein, mg/dL | 14.3 (6-23) | 679 (88) | 14.9 (7.07-24.6) | 13.2 (5.2-20.65) | .930 | 1.00 (0.99-1.01) |
| Procalcitonin, ng/mL | 0.4 (0.2-1.1) | 458 (59) | 0.4 (0.2-1.2) | 0.3 (0.19-0.9) | .993 | 1.01 (0.98-1.02) |
| Ferritin, ng/mL | 1,437 (822-2,472) | 210 (37) | 1,573 (1,026-2,553) | 1,213 (639-1,994) | .403 | 1.00 (0.99-1.01) |
| IL-6, ng/L | 200 (82-755) | 156 (21) | 166 (72-304) | 277 (93-1,206) | .942 | 1.00 (0.99-1.01) |
| Antibiotic therapy | … | 774 (100) | … | … | … | … |
| No antibiotic | 240 (31) | … | 130 (36) | 110 (27) | … | … |
| Narrow spectrumd | 294 (38) | … | 130 (36) | 164 (40) | .559 | 0.94 (0.75-1.17) |
| Broad spectrumd | 240 (31) | … | 99 (28) | 141 (34) | .038 | 0.82 (0.68-0.99) |
| Corticosteroidse | ||||||
| High dose | 36 (5) | 774 (100) | 17 (5) | 19 (5) | .347 | 0.90 (0.72-1.12) |
| Low dose | 171 (22) | 774 (100) | 80 (22) | 91 (22) | .023 | 0.66 (0.46-0.94) |
| Anakinrae | 89 (12) | 774 (100) | 52 (14) | 37 (9) | .821 | 0.94 (0.58-1.54) |
| Tocilizumabe | 187 (24) | 774 (100) | 85 (24) | 102 (25) | .099 | 2.12 (0.87-5.16) |
Data are presented as No. (%) of included patients or as median (interquartile range), unless otherwise indicated. APACHE = Acute Physiology and Chronic Health Evaluation; HR = hazard ratio; INR = international normalized ratio; LDH = lactate dehydrogenase; NC = not calculable; PBW = predicted body weight; PEEP = positive end expiratory pressure; SAPS = Simplified Acute Physiology Score; SOFA = Sequential Organ Failure Assessment; TV = tidal volume.
dvs no antibiotic.
a
Including chronic immunosuppressive therapies, active hematologic malignancies, neoplastic diseases, and autoimmune diseases.
b
vs Pao2 to Fio2 ratio of > 200.
c
vs pH of ≥ 7.35 and < 7.45.
e
At least 24 h before infection.