TABLE 2.
Baseline Characteristics by D-dimer Category
| D-dimer, Fold-Difference Above Upper Limit of Normal | |||||
|---|---|---|---|---|---|
| < 2× | 2–3.9× | 4–7.9× | ≥ 8× | ||
| Characteristics | All Patients (n = 3,418) | (n = 938) | (n = 875) | (n = 582) | (n = 1,023) |
| Demographics | |||||
| Age (yr), median (IQR) | 62 (51–71) | 59 (49–68) | 62 (51–71) | 64 (54–73) | 63 (51–71) |
| Male sex, n (%) | 2,170 (63.1) | 581 (61.9) | 626 (60.0) | 372 (63.9) | 692 (67.6) |
| Race, n (%) | |||||
| White | 1,315 (38.5) | 403 (43.0) | 336 (38.4) | 223 (38.3) | 353 (34.5) |
| Black | 1,030 (30.1) | 244 (26.0) | 292 (33.4) | 154 (26.5) | 340 (33.2) |
| Asian | 190 (5.6) | 57 (6.1) | 49 (5.6) | 41 (7.0) | 43 (4.2) |
| Other | 880 (25.7) | 233 (24.8) | 197 (22.5) | 164 (28.2) | 286 (28.0) |
| Hispanic, n (%) | 858 (25.1) | 280 (29.9) | 204 (23.3) | 126 (21.6) | 248 (24.2) |
| Body mass index, median (IQR) | 30 (27–36) | 31 (27–36) | 30 (26–36) | 30 (26–35) | 30 (26–35) |
| Pregnant, n (%) | 34 (1.0) | 13 (1.4) | 16 (1.8) | 3 (0.5) | 2 (0.2) |
| Coexisting conditions, n (%) | |||||
| Diabetes mellitus | 1,444 (42.2) | 366 (39.0) | 402 (45.9) | 250 (43.0) | 1,444 (42.2) |
| Hypertension | 2,089 (61.1) | 519 (55.3) | 531 (60.7) | 386 (66.3) | 653 (63.8) |
| Chronic obstructive pulmonary disease | 272 (8.0) | 91 (9.7) | 72 (8.2) | 49 (8.4) | 60 (5.9) |
| Current smoker | 160 (4.7) | 48 (5.1) | 38 (4.3) | 31 (5.3) | 43 (4.2) |
| Coronary artery disease | 436 (12.8) | 110 (11.7) | 123 (14.1) | 82 (14.1) | 121 (11.8) |
| Congestive heart failure | 332 (9.7) | 89 (9.5) | 72 (8.2) | 49 (8.4) | 60 (5.9) |
| Active malignancy | 142 (4.2) | 34 (3.6) | 39 (4.5) | 26 (4.5) | 43 (4.2) |
| ≤ 3 d from symptoms to ICU admission, n (%) | 726 (21.2) | 201 (21.4) | 184 (21.0) | 133 (22.9) | 208 (20.3) |
| Severity of illness within 2 d after ICU admission, n (%) | |||||
| Invasive mechanical ventilation | 2,359 (69.0) | 517 (55.1) | 563 (64.3) | 452 (77.7) | 827 (80.8) |
| Shock | 609 (17.8) | 106 (11.3) | 136 (15.5) | 107 (18.4) | 260 (25.4) |
| Lymphocyte count < 1,000 per mm3 | 1,501 (43.9) | 266 (28.4) | 318 (36.3) | 277 (47.6) | 640 (62.6) |
| Coagulation component of SOFA score | |||||
| 0 | 2,684 (78.5) | 726 (77.4) | 690 (78.9) | 455 (78.2) | 813 (79.5) |
| 1 | 533 (15.6) | 165 (17.6) | 142 (16.2) | 86 (14.8) | 140 (13.7) |
| ≥ 2 | 201 (5.9) | 47 (5.0) | 43 (4.9) | 41 (7.0) | 70 (6.8) |
| Liver component of SOFA score | |||||
| 0 | 2,933 (85.8) | 863 (92.0) | 777 (88.8) | 495 (85.1) | 798 (78.0) |
| 1 | 330 (9.7) | 54 (5.8) | 67 (7.7) | 62 (10.7) | 147 (14.4) |
| ≥ 2 | 155 (4.5) | 21 (2.2) | 31 (3.5) | 25 (4.3) | 78 (7.6) |
| Renal component of SOFA score | |||||
| 0 | 1,353 (39.6) | 495 (52.8) | 366 (41.8) | 214 (36.8) | 278 (27.2) |
| 1 | 641 (18.8) | 199 (21.2) | 170 (19.4) | 98 (16.8) | 174 (13.7) |
| ≥ 2 | 1,423 (41.7) | 244 (26.0) | 339 (38.7) | 270 (46.4) | 571 (55.8) |
| Medications affecting hemostasis, n (%) | |||||
| Therapeutic anticoagulation prior to hospital admission | 292 (8.5) | 100 (10.7) | 81 (9.3) | 55 (9.5) | 56 (5.5) |
| Therapeutic anticoagulation within 2 d after ICU admission | 916 (26.8) | 164 (17.5) | 194 (22.2) | 158 (27.1) | 400 (39.1) |
| Aspirin within 2 d after ICU admission | 527 (15.4) | 134 (14.3) | 143 (16.3) | 97 (16.7) | 153 (15.0) |
| Steroids within 2 d after ICU admission | 858 (25.1) | 146 (15.6) | 188 (21.5) | 169 (29.0) | 355 (34.7) |
IQR = interquartile range, SOFA = Sequential Organ Failure Assessment.
Shock is defined as need for ≥ 2 vasopressors. Data on body mass index and lymphocyte count were missing in 3.6% and 8.6% of patients, respectively. Data pertaining to at least one SOFA component score were missing in 5.4% of patients and categorized as 0. All other data are complete. The coagulation SOFA component score was calculated using the lowest measured platelet count within 2 d after ICU admission as follows: 0 points, ≥ 150 × 103/μL; 1 point, 100–149 × 103/μL; ≥ 2 points, < 100 × 103/μL. The liver SOFA component score was calculated using the highest bilirubin level within 2 d after ICU admission as follows: 0 points, < 1.2 mg/dL; 1 point, 1.2–1.9 mg/dL; ≥ 2 points, ≥ 2 mg/dL. The renal SOFA component score was calculated using the highest measured serum creatinine value, the lowest 24 hr urine output in the same time frame, and/or receipt of renal replacement therapy within 2 d after ICU admission, or end-stage renal disease status as follows: 0 points, creatinine < 1.2 mg/dL and urine output ≥ 500 mL/d; 1 point, creatinine 1.2–1.9 mg/dL and urine output ≥ 500 mL/d; ≥ 2 points, creatinine ≥ 2.0 mg/dL, urine output < 500 mL/d, receipt of acute renal replacement therapy, or end-stage renal disease. If urine output was missing, the category was assigned according to the serum creatinine.