Table 1.
Baseline characteristics of participants
| Variables | MIMIC-IV | P | eICU-CRD | P | ||
|---|---|---|---|---|---|---|
| Non-delirium patients (n = 3078) |
Delirium patients (n = 630) |
Non-delirium patients (n = 450) |
Delirium patients (n = 79) |
|||
| Age | 68.4 (61.4, 75.2) | 73.3 (64.9, 79.3) | < 0.01 | 66 (58, 73) | 70 (61, 76.5) | 0.05 |
| Sex Male, n (%) | 2419 (78.6) | 456 (72.4) | < 0.01 | 342 (76) | 56 (70.9) | 0.41 |
| BMI (kg/m2) | 28.3 (25.4, 32.2) | 28.1 (25.6, 32) | 0.55 | 29.2 (26.1, 33.5) | 29.3 (25.3, 34.6) | 0.91 |
| Vital signs | ||||||
| Temperature, (℃) | 36.7 (36.4, 36.9) | 36.7 (36.5, 36.9) | 0.92 | 36.3 (35.9, 36.8) | 36.3 (35.9, 36.8) | 0.92 |
| Heart rate, (min−1) | 80 (74, 89) | 81 (76, 88) | 0.39 | 84 (76.2, 90) | 89 (80, 96) | < 0.01 |
| Respiratory rate, (min−1) | 17 (15, 20.4) | 18 (15, 21) | 0.12 | 16 (12, 18) | 16 (14, 20.5) | 0.04 |
| Spo2, (%) | 98 (96, 100) | 99 (97, 100) | < 0.01 | 99 (96, 100) | 99 (96.5, 100) | 0.24 |
| Systolic BP, (mmHg) | 111 (101, 121) | 110 (100, 121) | 0.52 | 112 (103, 125) | 112 (106.5, 128) | 0.42 |
| Diastolic BP, (mmHg) | 56 (50, 63) | 55 (49, 61) | < 0.01 | 64 (57, 71) | 64 (60, 70) | 0.57 |
| Mean arterial BP, (mmHg) | 73 (67, 80) | 72 (66, 79) | < 0.01 | 79 (72, 84) | 79 (74, 87) | 0.13 |
| Laboratory tests | ||||||
| WBC, (K/uL) | 13.2 (10.3, 16.8) | 13.5 (10, 17.8) | 0.58 | 11.9 (9.1, 14.7) | 13.2 (9.8, 16.4) | 0.07 |
| Hemoglobin, (g/dL) | 10.2 (9.1, 11.3) | 9.7 (8.6, 10.8) | < 0.01 | 10.8 (9.5, 12.3) | 10.5 (8.9, 11.6) | 0.07 |
| Platelet, (K/uL) | 148.5 (122, 182) | 139.5 (110, 172) | < 0.01 | 147 (115, 183) | 134 (97.5, 158) | < 0.01 |
| Creatinine, (mg/dl) | 0.9 (0.7, 1.1) | 1 (0.8, 1.3) | < 0.01 | 0.9 (0.8, 1.1) | 1.1 (0.8, 1.4) | < 0.01 |
| BUN, (mg/dl) | 15 (13, 20) | 17 (14, 23) | < 0.01 | 15 (11, 20) | 16 (14, 22) | 0.01 |
| Glucose, (mg/dl) | 136 (117, 161) | 138 (116, 168) | 0.15 | 128 (112, 152.8) | 132 (118, 166.5) | 0.15 |
| Sodium, (mEq/L) | 136 (134, 138) | 136 (134, 138) | 0.49 | 139 (136, 141) | 139 (136, 141) | 0.99 |
| Chloride, (mEq/L) | 107 (104, 109) | 107 (104, 109) | 0.14 | 106 (104, 109) | 107 (104.5, 109) | 0.26 |
| Potassium, (mEq/L) | 4.4 (4, 4.8) | 4.3 (3.9, 4.8) | 0.15 | 4.1 (3.8, 4.4) | 4.2 (3.8, 4.6) | 0.15 |
| Magnesium, (mg/dl) | 2.4 (2.2, 2.6) | 2.5 (2.3, 2.9) | < 0.01 | 2.3 (2, 2.8) | 2.3 (2.1, 2.6) | 0.92 |
| Bicarbonate, (mEq/L) | 23 (22, 24) | 22 (21, 24) | < 0.01 | 23 (22, 25) | 23 (21, 24) | 0.13 |
| Anion gap, (mEq/L) | 12 (10, 13) | 12 (10, 14) | < 0.01 | 8 (7, 9) | 8 (7, 11) | 0.22 |
| pH | 7.4 (7.3, 7.4) | 7.4 (7.3, 7.4) | 0.68 | 7.4 (7.3, 7.4) | 7.3 (7.3, 7.4) | 0.01 |
| Treatment measures | ||||||
| MV, n (%) | 1791 (58.2) | 490 (77.8) | < 0.01 | 328 (72.9) | 66 (83.5) | 0.06 |
| Vasopressor, n (%) | 2437 (79.2) | 560 (88.9) | < 0.01 | 202 (44.9) | 38 (48.1) | 0.68 |
| CRRT, n (%) | 21 (0.7) | 18 (2.9) | < 0.01 | 6 (1.3) | 1 (1.3) | 1.00 |
| Dexmedetomidine, n (%) | 662 (21.5) | 186 (29.5) | < 0.01 | 169 (37.6) | 33 (41.8) | 0.56 |
| Propofol, n (%) | 3001 (97.5) | 616 (97.8) | 0.79 | 19 (4.2) | 6 (7.6) | 0.24 |
| Midazolam, n (%) | 51 (1.7) | 34 (5.4) | < 0.01 | 106 (23.6) | 7 (8.9) | < 0.01 |
| Scores | ||||||
| GCS | 15 (14, 15) | 15 (14, 15) | 0.46 | 14 (10, 15) | 12 (9, 15) | < 0.01 |
| SOFA | 5 (4, 7) | 7 (5, 9) | < 0.01 | 6 (4, 9) | 8 (6, 10) | < 0.01 |
| RASS | −0.5 (−1, 0) | −2 (−4, −0.5) | < 0.01 | 0 (−1, 0) | −1 (−2, 0) | < 0.01 |
| Pain | 5 (4, 6.5) | 5 (3, 6.5) | < 0.01 | 5 (4, 6) | 5 (4, 5) | 0.42 |
| Comorbidities | ||||||
| CHF, n (%) | 577 (18.7) | 236 (37.5) | < 0.01 | 38 (8.4) | 7 (8.9) | 1.00 |
| CKD, n (%) | 486 (15.8) | 179 (28.4) | < 0.01 | 20 (4.4) | 6 (7.6) | 0.26 |
| Hypertension, n (%) | 1930 (62.7) | 318 (50.5) | < 0.01 | 109 (24.2) | 21 (26.6) | 0.76 |
| Diabetes, n (%) | 774 (25.1) | 164 (26) | 0.68 | 100 (22.2) | 10 (12.7) | 0.07 |
| Stroke, n (%) | 59 (1.9) | 18 (2.9) | 0.18 | 24 (5.3) | 5 (6.3) | 0.79 |
Abbreviations:BMI body mass index, BP blood pressure, WBC white blood cell count, BUN blood urea nitrogen, MV mechanical ventilation, CRRT continuous renal replacement therapy, GCS Glasgow Coma Scale, SOFA Sequential Organ Failure Assessment, RASS Richmond Agitation-Sedation Scale, CHF congestive heart failure, CKD chronic kidney disease