Characteristics of participants
| Total (n=1177) | Derivation group (n=825) | Validation group (n=352) | P value for derivation vs validation | Alive (n=1017) | Died (n=159) | P value for alive vs dead | |
| Age, mean (SD), years | 74.06 (13.43) | 74.05 (13.49) | 74.06 (13.32) | 0.998 | 73.71 (13.45) | 76.24 (13.22) | 0.027 |
| BMI, mean (SD) | 29.88 (7.94) | 30.00 (8.23) | 29.59 (7.25) | 0.467 | 30.11 (8.07) | 28.17 (6.67) | 0.016 |
| Heart rate, mean (SD), bpm | 84.58 (16.02) | 84.52 (15.84) | 84.70 (16.45) | 0.863 | 83.75 (15.99) | 89.82 (15.25) | <0.001 |
| Systolic blood pressure, mean (SD), mm Hg | 118.00 (17.37) | 118.71 (17.90) | 116.33 (15.95) | 0.032 | 118.91 (17.32) | 112.18 (16.61) | <0.001 |
| Diastolic blood pressure, mean (SD), mm Hg | 59.53 (10.68) | 59.64 (10.50) | 59.30 (11.12) | 0.618 | 59.90 (10.90) | 57.18 (8.88) | 0.003 |
| Mean blood pressure, mean (SD), mm Hg | 75.20 (10.62) | 75.44 (10.70) | 74.64 (10.43) | 0.239 | 75.60 (10.69) | 72.65 (9.84) | 0.001 |
| Respiratory rate, mean (SD), bpm | 20.80 (4.00) | 20.82 (3.99) | 20.76 (4.03) | 0.821 | 20.62 (3.90) | 21.98 (4.42) | <0.001 |
| Temperature, mean (SD), °C | 36.68 (0.61) | 36.68 (0.61) | 36.66 (0.61) | 0.512 | 36.70 (0.59) | 36.54 (0.70) | 0.002 |
| SPO2, mean (SD), % | 96.27 (2.30) | 96.24 (2.34) | 96.35 (2.19) | 0.458 | 96.34 (2.14) | 95.86 (3.10) | 0.015 |
| Urine-output (first 24 hours), median (Q1–Q3), mL | 1675.00 (992.50–2480.00) | 1630.00 (1000.00–2475.00) | 1717.50 (938.50–2488.75) | 0.932 | 1773.50 (1078.75–2586.25) | 1050.00 (674.50–1626.50) | <0.001 |
| LVEF, mean (SD), % | 48.72 (12.87) | 48.82 (12.74) | 48.48 (13.18) | 0.679 | 48.83 (12.55) | 47.92 (14.77) | 0.408 |
| Haematocrit, mean (SD), % | 31.91 (5.20) | 31.77 (5.13) | 32.25 (5.36) | 0.151 | 31.94 (5.19) | 31.69 (5.27) | 0.571 |
| Red cells, mean (SD), ×10∧12/L | 3.58 (0.63) | 3.55 (0.62) | 3.62 (0.65) | 0.088 | 3.58 (0.62) | 3.54 (0.70) | 0.411 |
| MCH, mean (SD), pg | 29.54 (2.62) | 29.58 (2.59) | 29.44 (2.69) | 0.394 | 29.53 (2.58) | 29.63 (2.87) | 0.647 |
| MCHC, mean (SD), % | 32.86 (1.40) | 32.87 (1.40) | 32.84 (1.40) | 0.701 | 32.88 (1.41) | 32.75 (1.36) | 0.275 |
| MCV, mean (SD), fL | 89.90 (6.53) | 90.01 (6.47) | 89.66 (6.67) | 0.396 | 89.81 (6.43) | 90.47 (7.16) | 0.242 |
| RDW, mean (SD), % | 15.95 (2.13) | 16.01 (2.25) | 15.81 (1.82) | 0.139 | 15.83 (2.07) | 16.75 (2.33) | <0.001 |
| White cells, mean (SD), /×10∧9/L | 10.54 (4.29) | 10.54 (4.31) | 10.53 (4.23) | 0.980 | 10.20 (4.11) | 12.78 (4.78) | <0.001 |
| Platelet count, median (Q1–Q3), ×10∧9/L | 222.67 (168.91–304.25) | 222.12 (168.91–301.38) | 224.03 (168.97–306.78) | 0.582 | 226.09 (173.40–305.33) | 198.56 (134.68–262.07) | <0.001 |
| Neutrophils, mean (SD), % | 80.11 (11.13) | 79.99 (10.63) | 80.39 (12.21) | 0.591 | 79.79 (10.41) | 82.12 (14.77) | 0.020 |
| Basophils, median (Q1–Q3), % | 0.30 (0.20–0.50) | 0.30 (0.20–0.50) | 0.30 (0.20–0.50) | 0.286 | 0.30 (0.20–0.50) | 0.20 (0.10–0.40) | <0.001 |
| Lymphocytes, median (Q1–Q3), % | 10.48 (6.65–15.46) | 10.62 (6.94–15.31) | 10.00 (6.10–16.18) | 0.870 | 11.00 (7.10–16.00) | 7.00 (4.14–10.53) | <0.001 |
| PT, mean (SD), s | 17.48 (7.39) | 17.40 (7.13) | 17.66 (7.98) | 0.585 | 17.07 (6.50) | 20.09 (11.18) | <0.001 |
| INR, median (Q1–Q3) | 1.30 (1.14–1.74) | 1.30 (1.15–1.75) | 1.30 (1.13–1.70) | 0.461 | 1.28 (1.13–1.70) | 1.46 (1.20–2.00) | <0.001 |
| NT-proBNP, median (Q1–Q3), pg/mL | 5840.00 (2251.00–14 968.00) | 6217.00 (2341.00–15 555.00) | 4994.00 (2088.38–13 629.75) | 0.102 | 5302.00 (2143.00–13 666.50) | 9469.00 (3082.50–3662.75) | <0.001 |
| Creatine kinase (CK), median (Q1–Q3), IU/L | 89.25 (46.00–185.19) | 85.00 (46.92–185.88) | 99.00 (44.00–185.00) | 0.509 | 90.00 (47.00–182.13) | 83.12 (37.85–38.63) | 0.794 |
| Creatinine, median (Q1–Q3), mg/dL | 1.29 (0.94–1.90) | 1.27 (0.94–1.88) | 1.33 (0.95–1.94) | 0.549 | 1.25 (0.93–1.81) | 1.45 (0.97–2.21) | 0.007 |
| Blood urea nitrogen, median (Q1–Q3), mg/dL | 30.67 (20.83–45.25) | 30.67 (20.56–45.08) | 30.49 (22.25–45.36) | 0.580 | 29.25 (20.11–43.00) | 39.62 (27.06–57.16) | <0.001 |
| Glucose, mean (SD), mEq/L | 148.80 (51.49) | 148.07 (52.09) | 150.49 (50.12) | 0.462 | 148.14 (50.46) | 153.01 (57.63) | 0.270 |
| Potassium, mean (SD), mEq/L | 4.18 (0.41) | 4.17 (0.41) | 4.18 (0.42) | 0.662 | 4.15 (0.39) | 4.32 (0.53) | <0.001 |
| Sodium, mean (SD), mEq/L | 138.89 (4.15) | 138.85 (4.17) | 138.98 (4.12) | 0.636 | 139.01 (3.98) | 138.20 (5.02) | 0.023 |
| Calcium, total, mean (SD), mg/dL | 8.50 (0.57) | 8.49 (0.58) | 8.54 (0.56) | 0.169 | 8.54 (0.55) | 8.24 (0.62) | <0.001 |
| Chloride, mean (SD), mEq/L | 102.28 (5.34) | 102.27 (5.43) | 102.32 (5.14) | 0.875 | 102.17 (5.21) | 103.10 (6.00) | 0.040 |
| Anion gap, mean (SD), mEq/L | 13.93 (2.65) | 13.91 (2.68) | 13.96 (2.58) | 0.763 | 13.68 (2.41) | 15.46 (3.52) | <0.001 |
| Magnesium, mean (SD), mg/dL | 2.12 (0.25) | 2.12 (0.26) | 2.13 (0.24) | 0.420 | 2.11 (0.24) | 2.17 (0.29) | 0.011 |
| PH, mean (SD) | 7.38 (0.07) | 7.38 (0.07) | 7.37 (0.07) | 0.041 | 7.38 (0.06) | 7.36 (0.07) | <0.001 |
| Bicarbonate, mean (SD), mEq/L | 26.91 (5.17) | 26.90 (5.23) | 26.94 (5.02) | 0.906 | 27.37 (4.98) | 24.00 (5.42) | <0.001 |
| Lactate, median (Q1–Q3), mmol/L | 1.60 (1.20–2.20) | 1.60 (1.20–2.20) | 1.65 (1.25–2.20) | 0.309 | 1.60 (1.20–2.10) | 2.00 (1.36–3.08) | <0.001 |
| PCO2, mean (SD), mm Hg | 45.54 (12.86) | 45.48 (12.95) | 45.67 (12.65) | 0.846 | 45.82 (12.85) | 44.07 (12.85) | 0.141 |
| Gender | 0.685 | 0.437 | |||||
| Male (n, %) | 559 (47.49%) | 395 (47.88%) | 164 (46.59%) | 478 (47.00%) | 80 (50.31%) | ||
| Female (n, %) | 618 (52.51%) | 430 (52.12%) | 188 (53.41%) | 539 (53.00%) | 79 (49.69%) | ||
| Hypertension | 0.072 | 0.013 | |||||
| No (n, %) | 332 (28.21%) | 220 (26.67%) | 112 (31.82%) | 274 (26.94%) | 58 (36.48%) | ||
| Yes (n, %) | 845 (71.79%) | 605 (73.33%) | 240 (68.18%) | 743 (73.06%) | 101 (63.52%) | ||
| Atrial fibrillation | 0.918 | <0.001 | |||||
| No (n, %) | 646 (54.89%) | 452 (54.79%) | 194 (55.11%) | 578 (56.83%) | 67 (42.14%) | ||
| Yes (n, %) | 531 (45.11%) | 373 (45.21%) | 158 (44.89%) | 439 (43.17%) | 92 (57.86%) | ||
| Ischaemic heart disease | 0.857 | 0.614 | |||||
| No (n, %) | 1076 (91.42%) | 755 (91.52%) | 321 (91.19%) | 928 (91.25%) | 147 (92.45%) | ||
| Yes (n, %) | 101 (8.58%) | 70 (8.48%) | 31 (8.81%) | 89 (8.75%) | 12 (7.55%) | ||
| Diabetes mellitus | 0.390 | 0.086 | |||||
| No (n, %) | 681 (57.86%) | 484 (58.67%) | 197 (55.97%) | 579 (56.93%) | 102 (64.15%) | ||
| Yes (n, %) | 496 (42.14%) | 341 (41.33%) | 155 (44.03%) | 438 (43.07%) | 57 (35.85%) | ||
| Hypoferric anaemia | 0.822 | <0.001 | |||||
| No (n, %) | 778 (66.10%) | 547 (66.30%) | 231 (65.62%) | 653 (64.21%) | 124 (77.99%) | ||
| Yes (n, %) | 399 (33.90%) | 278 (33.70%) | 121 (34.38%) | 364 (35.79%) | 35 (22.01%) | ||
| Depression | 0.417 | 0.037 | |||||
| No (n, %) | 1037 (88.11%) | 731 (88.61%) | 306 (86.93%) | 888 (87.32%) | 148 (93.08%) | ||
| Yes (n, %) | 140 (11.89%) | 94 (11.39%) | 46 (13.07%) | 129 (12.68%) | 11 (6.92%) | ||
| Hyperlipidaemia | 0.275 | 0.067 | |||||
| No (n, %) | 730 (62.02%) | 520 (63.03%) | 210 (59.66%) | 620 (60.96%) | 109 (68.55%) | ||
| Yes (n, %) | 447 (37.98%) | 305 (36.97%) | 142 (40.34%) | 397 (39.04%) | 50 (31.45%) | ||
| Chronic renal insufficiency | 0.937 | <0.001 | |||||
| No (n, %) | 747 (63.47%) | 523 (63.39%) | 224 (63.64%) | 625 (61.46%) | 122 (76.73%) | ||
| Yes (n, %) | 430 (36.53%) | 302 (36.61%) | 128 (36.36%) | 392 (38.54%) | 37 (23.27%) | ||
| Chronic obstructive pulmonary disease | 0.697 | 0.105 | |||||
| No (n, %) | 1088 (92.44%) | 761 (92.24%) | 327 (92.90%) | 935 (91.94%) | 152 (95.60%) | ||
| Yes (n, %) | 89 (7.56%) | 64 (7.76%) | 25 (7.10%) | 82 (8.06%) | 7 (4.40%) | ||
| Race/ethnicity | 0.265 | 0.021 | |||||
| Non-black (n, %) | 1020 (86.66%) | 709 (85.94%) | 311 (88.35%) | 872 (85.74%) | 147 (92.45%) | ||
| Black (n, %) | 159 (13.52%) | 116 (14.06%) | 41 (11.65%) | 145 (14.26%) | 12 (7.55%) | ||
| In-hospital death | 0.406 | – | |||||
| No (n, %) | 1017 (86.48%) | 709 (85.94%) | 308 (87.75%) | – | – | ||
| Yes (n, %) | 159 (13.52%) | 116 (14.06%) | 43 (12.25%) | – | – |
Data are presented as mean±SD, % or median (IQR).
BMI, body mass index; INR, international normalised ratio; LVEF, left ventricular ejection fraction; MCH, mean corpuscular haemoglobin; MCHC, mean corpuscular haemoglobin concentration; MCV, mean corpuscular volume; NT-proBNP, N-terminal pro-brain natriuretic peptide; PaCO2, partial pressure of carbon dioxide in artery; PH, hydrogen ion concentration; PT, lymphocytes, prothrombin time; RDW, red blood cell distribution width; SPO2, saturation pulse oxygen.