Table 1.
Baseline characteristics and in-hospital outcomes of patients hospitalized due to COVID-19 infection and stratified by hemoglobin level
| Hb < 10 g/dL N = 1045 | Hb 10- 12 g/dL N = 1871 | Hb 12- 14 g/dL N = 3408 | Hb 14- 16 g/dL N = 2555 | Hb ≥ 16 g/dL N = 588 | P value | |
|---|---|---|---|---|---|---|
| Demographics and comorbidities | ||||||
| Age (years), mean (SD) | 66.9 (16.5) | 67.7 (17.2) | 65.4 (16.7) | 62.5 (16.8) | 60.6 (17.2) | < 0.001 |
| Male, n (%) | 492 (47.1) | 760 (40.6) | 1600 (46.9) | 1834 (71.8) | 498 (84.7) | < 0.001 |
| Race, n (%) | < 0.001 | |||||
| White | 257 (24.6) | 534 (28.5) | 980 (28.8) | 667 (26.1) | 148 (25.2) | |
| African American | 345 (33.0) | 510 (27.3) | 814 (23.9) | 504 (19.7) | 107 (18.2) | |
| Hispanic | 240 (23.0) | 442 (23.6) | 833 (24.4) | 735 (28.8) | 169 (28.7) | |
| Asian | 56 ( 5.4) | 112 ( 6.0) | 203 ( 6.0) | 153 ( 6.0) | 33 ( 5.6) | |
| Others | 147 (14.1) | 273 (14.6) | 578 (17.0) | 496 (19.4) | 131 (22.3) | |
| Comorbidities | ||||||
| COPD, n (%) | 58 ( 5.6) | 109 ( 5.8) | 128 ( 3.8) | 108 ( 4.2) | 18 ( 3.1) | 0.001 |
| Hypertension, n (%) | 525 (50.2) | 837 (44.7) | 1155 (33.9) | 761 (29.8) | 161 (27.4) | < 0.001 |
| Diabetes mellitus, n (%) | 366 (35.0) | 579 (30.9) | 706 (20.7) | 452 (17.7) | 124 (21.1) | < 0.001 |
| Obstructive sleep apnea, n (%) | 31 ( 3.0) | 64 ( 3.4) | 67 ( 2.0) | 54 ( 2.1) | 7 ( 1.2) | 0.002 |
| Obesity, n (%) | 99 ( 9.5) | 182 ( 9.7) | 300 ( 8.8) | 216 ( 8.5) | 37 ( 6.3) | 0.11 |
| Atrial fibrillation, n (%) | 131 (12.5) | 183 ( 9.8) | 229 ( 6.7) | 172 ( 6.7) | 46 ( 7.8) | < 0.001 |
| Heart failure, n (%) | 198 (18.9) | 259 (13.8) | 240 ( 7.0) | 115 ( 4.5) | 32 ( 5.4) | < 0.001 |
| Coronary artery disease, n (%) | 233 (22.3) | 347 (18.5) | 434 (12.7) | 296 (11.6) | 66 (11.2) | < 0.001 |
| Vital signs | ||||||
| Respiratory rate (/min), mean (SD) | 20.4 (4.8) | 20.5 (5.0) | 20.6 (5.1) | 21.0 (6.1) | 21.2 (6.3) | 0.001 |
| O2 Saturation (%), mean (SD) | 82.7 (19.5) | 84.0 (18.1) | 84.8 (16.1) | 83.6 (17.7) | 83.1 (19.0) | 0.003 |
| Blood tests | ||||||
| White blood cell (K/μL), median [IQR] | 7.6 [5.1, 11.2] | 7.4 [5.3, 10.5] | 7.1 [5.3, 10.0] | 7.5 [5.6, 10.4] | 7.9 [5.9, 11.3] | < 0.001 |
| Hemoglobin (g/dL), median [IQR] | 8.9 [8.1, 9.5] | 11.1 [10.6, 11.6] | 13.0 [12.5, 13.5] | 14.7 [14.3, 15.2] | 16.5 [16.2, 17.0] | < 0.001 |
| Platelet (K/μL), median [IQR] | 218.0 [149.0, 305.0] | 211.0 [157.0, 281.0] | 205.0 [157.0, 265.0] | 201.0 [155.0, 256.0] | 183.0 [143.0, 247.0] | < 0.001 |
| eGFR (ml/min./1.73m2), median [IQR] | 37.7 [15.4, 75.1] | 55.0 [29.2, 86.5] | 73.2 [49.8, 97.3] | 76.0 [54.2, 96.5] | 73.9 [52.8, 90.7] | < 0.001 |
| C reactive protein (mg/L), median [IQR] | 97.2 [37.0, 183.9] | 82.0 [34.9, 164.1] | 85.7 [36.4, 162.2] | 92.8 [43.1, 171.7] | 83.4 [38.5, 149.6] | 0.001 |
| D-Dimer (μg/mL), median [IQR] | 2.19 [1.18, 3.81] | 1.76 [0.98, 3.09] | 1.24 [0.70, 2.30] | 1.11 [0.65, 2.06] | 1.16 [0.66, 2.47] | < 0.001 |
| Treatment | ||||||
| Therapeutic anticoagulation, n (%) | 411 (39.3) | 705 (37.7) | 1152 (33.8) | 893 (35.0) | 213 (36.2) | 0.004 |
| Prophylactic anticoagulation, n (%) | 465 (44.5) | 981 (52.4) | 1970 (57.8) | 1465 (57.3) | 311 (52.9) | < 0.001 |
| Steroid treatment, n (%) | 426 (40.8) | 900 (48.1) | 1740 (51.1) | 1360 (53.2) | 299 (50.9) | < 0.001 |
| IL-6 inhibitor, n (%) | 16 ( 1.5) | 39 ( 2.1) | 134 ( 3.9) | 115 ( 4.5) | 19 ( 3.2) | < 0.001 |
| Convalescent Plasma, n (%) | 103 ( 9.9) | 212 (11.3) | 416 (12.2) | 310 (12.1) | 69 (11.7) | 0.29 |
| Use of Remdesivir, n (%) | 85 ( 8.1) | 246 (13.1) | 640 (18.8) | 514 (20.1) | 107 (18.2) | < 0.001 |
| In-hospital outcomes | ||||||
| In-hospital mortality | 348 (33.3) | 494 (26.4) | 681 (20.0) | 530 (20.7) | 148 (25.2) | < 0.001 |
| Intensive care unit admission | 234 (22.4) | 363 (19.4) | 632 (18.5) | 530 (20.7) | 140 (23.8) | 0.005 |
| Endotracheal intubation | 176 (16.8) | 242 (12.9) | 413 (12.1) | 336 (13.2) | 87 (14.8) | 0.002 |
| Acute kidney injury | 498 (47.9) | 636 (34.8) | 770 (23.0) | 556 (21.9) | 141 (24.1) | < 0.001 |
| Acute venous thromboembolism | 14 ( 1.3) | 24 ( 1.3) | 42 ( 1.2) | 23 ( 0.9) | 10 ( 1.7) | 0.48 |
COPD chronic obstructive pulmonary disease, eGFR estimated glomerular filtration rate, Hb hemoglobin, IL interleukin, IQR interquartile range, SD standard deviation