Table 1.
Patient characteristics and demographics grouped by ICU admission status.
| Characteristic | N | Overall, N = 781 | Not admitted to ICU, N = 511 | Admitted to ICU, N = 271 | p-value2 |
|---|---|---|---|---|---|
| Dataset split | 78 | 0.43 | |||
| Test | 48 (62%) | 33 (65%) | 15 (56%) | ||
| Training | 30 (38%) | 18 (35%) | 12 (44%) | ||
| Symptom duration days | 78 | 7 (5, 10) | 7 (4, 10) | 8 (6, 10) | 0.43 |
| LOS (hours) | 75 | 198 (100, 332) | 147 (59, 256) | 296 (214, 546) | <0.001 |
| Age | 78 | 61 (46, 74) | 70 (49, 80) | 56 (45, 61) | 0.006 |
| Sex | 78 | 0.61 | |||
| F | 26 (33%) | 18 (35%) | 8 (30%) | ||
| M | 52 (67%) | 33 (65%) | 19 (70%) | ||
| Smoking status | 78 | 0.91 | |||
| Ex-smoker | 31 (40%) | 21 (41%) | 10 (37%) | ||
| Never | 36 (46%) | 22 (43%) | 14 (52%) | ||
| Unknown | 7 (9.0%) | 5 (9.8%) | 2 (7.4%) | ||
| Yes | 4 (5.1%) | 3 (5.9%) | 1 (3.7%) | ||
| Ethnicity | 78 | 0.037 | |||
| White - British | 47 (60%) | 33 (65%) | 14 (52%) | ||
| White – Any other white background | 6 (7.7%) | 6 (12%) | 0 (0%) | ||
| Asian or Asian British - Indian | 3 (3.8%) | 2 (3.9%) | 1 (3.7%) | ||
| Asian or Asian British – Any other Asian background | 13 (17%) | 5 (9.8%) | 8 (30%) | ||
| Black or Black British - Caribbean | 2 (2.6%) | 2 (3.9%) | 0 (0%) | ||
| Black or Black British - African | 6 (7.7%) | 2 (3.9%) | 4 (15%) | ||
| Unknown | 1 (1.3%) | 1 (2.0%) | 0 (0%) | ||
| Clinical Metrics | |||||
| Hypertension | 78 | 0.72 | |||
| No | 45 (58%) | 29 (57%) | 16 (59%) | ||
| Unknown | 4 (5.1%) | 2 (3.9%) | 2 (7.4%) | ||
| Yes | 29 (37%) | 20 (39%) | 9 (33%) | ||
| CV disease | 78 | 0.17 | |||
| No | 59 (76%) | 37 (73%) | 22 (81%) | ||
| Unknown | 3 (3.8%) | 1 (2.0%) | 2 (7.4%) | ||
| Yes | 16 (21%) | 13 (25%) | 3 (11%) | ||
| Resp Disease other | 78 | 0.47 | |||
| No | 54 (69%) | 35 (69%) | 19 (70%) | ||
| Unknown | 3 (3.8%) | 1 (2.0%) | 2 (7.4%) | ||
| Yes | 21 (27%) | 15 (29%) | 6 (22%) | ||
| Asthma | 78 | 0.51 | |||
| No | 62 (79%) | 41 (80%) | 21 (78%) | ||
| Unknown | 3 (3.8%) | 1 (2.0%) | 2 (7.4%) | ||
| Yes | 13 (17%) | 9 (18%) | 4 (15%) | ||
| COPD | 78 | 0.49 | |||
| No | 68 (87%) | 45 (88%) | 23 (85%) | ||
| Unknown | 3 (3.8%) | 1 (2.0%) | 2 (7.4%) | ||
| Yes | 7 (9.0%) | 5 (9.8%) | 2 (7.4%) | ||
| CKD | 78 | 0.53 | |||
| No | 69 (88%) | 46 (90%) | 23 (85%) | ||
| Unknown | 3 (3.8%) | 1 (2.0%) | 2 (7.4%) | ||
| Yes | 6 (7.7%) | 4 (7.8%) | 2 (7.4%) | ||
| CLD | 78 | 0.55 | |||
| No | 72 (92%) | 48 (94%) | 24 (89%) | ||
| Unknown | 3 (3.8%) | 1 (2.0%) | 2 (7.4%) | ||
| Yes | 3 (3.8%) | 2 (3.9%) | 1 (3.7%) | ||
| Diabetes | 78 | 0.50 | |||
| No | 56 (72%) | 38 (75%) | 18 (67%) | ||
| Unknown | 3 (3.8%) | 1 (2.0%) | 2 (7.4%) | ||
| Yes | 19 (24%) | 12 (24%) | 7 (26%) | ||
| Active malignancy | 78 | 0.11 | |||
| No | 69 (88%) | 44 (86%) | 25 (93%) | ||
| Unknown | 3 (3.8%) | 1 (2.0%) | 2 (7.4%) | ||
| Yes | 6 (7.7%) | 6 (12%) | 0 (0%) | ||
| Dementia | 78 | 0.048 | |||
| No | 67 (86%) | 42 (82%) | 25 (93%) | ||
| Unknown | 3 (3.8%) | 1 (2.0%) | 2 (7.4%) | ||
| Yes | 8 (10%) | 8 (16%) | 0 (0%) | ||
| Immunosuppressed+ | 78 | 0.16 | |||
| No | 70 (90%) | 48 (94%) | 22 (81%) | ||
| Unknown | 4 (5.1%) | 1 (2.0%) | 3 (11%) | ||
| Yes | 4 (5.1%) | 2 (3.9%) | 2 (7.4%) | ||
| Abx during admission | 78 | 72 (92%) | 46 (90%) | 26 (96%) | 0.66 |
| Blood chemistry | |||||
| Haemoglobin | 77 | 132 (124, 148) | 132 (122, 140) | 144 (128, 151) | 0.20 |
| White blood cells | 77 | 7.8 (5.7, 11.5) | 6.2 (4.9, 10.7) | 9.4 (6.8, 11.5) | 0.026 |
| Platelets | 77 | 236 (184, 291) | 227 (182, 280) | 255 (186, 294) | 0.45 |
| Neutrophils | 77 | 6.0 (4.0, 9.6) | 4.8 (3.6, 8.1) | 8.2 (5.2, 9.7) | 0.012 |
| Lymphocytes | 77 | 1.00 (0.80, 1.20) | 1.00 (0.80, 1.18) | 1.00 (0.75, 1.30) | 0.72 |
| Sodium | 77 | 135 (133, 138) | 136 (133, 138) | 135 (132, 136) | 0.091 |
| Potassium | 71 | 4.00 (3.65, 4.40) | 3.90 (3.65, 4.35) | 4.00 (3.75, 4.43) | 0.44 |
| Urea | 77 | 6.3 (4.7, 9.9) | 6.4 (4.3, 10.1) | 6.3 (4.8, 8.9) | 0.95 |
| Creatine | 77 | 86 (67, 110) | 84 (67, 109) | 88 (66, 108) | 0.79 |
| Albumin | 73 | 34 (30, 35) | 34 (31, 36) | 31 (28, 34) | 0.009 |
| Bilirubin | 73 | 11 (8, 13) | 10 (8, 12) | 11 (10, 14) | 0.063 |
| Alanine Aminotransferase | 70 | 34 (24, 70) | 28 (21, 56) | 37 (32, 77) | 0.050 |
| Alkaline Phosphatase | 73 | 89 (61, 115) | 80 (56, 110) | 96 (62, 124) | 0.12 |
| Total Protein | 72 | 70 (66, 73) | 70 (67, 73) | 71 (66, 74) | 0.85 |
| LDH | 52 | 766 (561, 1,133) | 650 (506, 776) | 1,130 (850, 1,382) | <0.001 |
| Ferritin | 61 | 678 (354, 1,693) | 521 (203, 750) | 1,427 (908, 2,073) | <0.001 |
| D-dimer | 45 | 469 (320, 942) | 456 (298, 1,426) | 535 (385, 812) | 0.53 |
| Trop | 60 | 12 (5, 46) | 11 (4, 28) | 12 (8, 63) | 0.25 |
| CRP | 77 | 120 (52, 164) | 80 (22, 131) | 168 (128, 254) | <0.001 |
| Cytokines/Chemokines | |||||
| IL-6 (pg/mL) | 78 | 52 (32, 106) | 43 (30, 85) | 82 (43, 132) | 0.030 |
| TNFα (pg/mL) | 78 | 20 (17, 25) | 20 (16, 25) | 22 (19, 25) | 0.27 |
| IL-8 (pg/mL) | 78 | 35 (26, 59) | 34 (25, 53) | 49 (34, 64) | 0.10 |
| IL-1β9 (pg/mL) | 78 | 0.39 (0.26, 0.56) | 0.35 (0.24, 0.48) | 0.47 (0.31, 0.66) | 0.056 |
| GM-CSF (pg/mL) | 78 | 1.30 (0.80, 1.86) | 1.20 (0.77, 2.28) | 1.49 (1.01, 1.79) | 0.43 |
| IFNg (pg/mL) | 78 | 12 (4, 27) | 9 (2, 27) | 16 (8, 35) | 0.072 |
| IL-10 (pg/mL) | 78 | 16 (10, 28) | 15 (8, 27) | 17 (13, 29) | 0.22 |
| IL-33 (pg/mL) | 78 | 0.35 (0.17, 0.61) | 0.28 (0.15, 0.39) | 0.46 (0.35, 0.91) | 0.009 |
| Physiological Metrics | |||||
| Heart Rate | 78 | 98 (85, 109) | 92 (82, 107) | 102 (94, 110) | 0.064 |
| Systolic Blood Pressure | 78 | 132 (122, 143) | 135 (122, 145) | 128 (124, 134) | 0.14 |
| Respiration rate | 78 | 26 (20, 32) | 24 (20, 28) | 28 (23, 34) | 0.054 |
| Oxygen Saturation | 78 | 95 (92, 96) | 96 (93, 97) | 95 (90, 96) | 0.047 |
| Temperature (°C) | 76 | 37.20 (36.60, 38.20) | 37.20 (36.65, 38.10) | 37.20 (36.60, 38.40) | 0.61 |
| O2 | 78 | 37 (47%) | 17 (33%) | 20 (74%) | <0.001 |
| NEWS2 | 76 | 6 (4, 7) | 5 (2, 6) | 6 (5, 8) | 0.012 |
| CXR | 78 | 77 (99%) | 50 (98%) | 27 (100%) | >0.99 |
| Consolidation or infiltrates | 77 | 66 (86%) | 39 (78%) | 27 (100%) | 0.007 |
| CT | 78 | 8 (10%) | 5 (9.8%) | 3 (11%) | >0.99 |
| ICU specific metrics | |||||
| Duration O2 | 78 | 19 (5, 112) | 9 (1, 17) | 161 (110, 397) | <0.001 |
| NIV duration | 78 | 0 (0, 13) | 0 (0, 0) | 25 (6, 49) | <0.001 |
| IV duration | 78 | 0 (0, 0) | 0 (0, 0) | 114 (0, 277) | <0.001 |
| Optiflow duration | 78 | 7 (9.0%) | 0 (0%) | 7 (26%) | <0.001 |
| ECMO | 75 | 1 (1.3%) | 0 (0%) | 1 (4.2%) | 0.32 |
| Died within 30 days of admission | 77 | 15 (19%) | 12 (24%) | 3 (12%) | 0.21 |
1n (%); Median (IQR) 2 arson’s Chi-squared test; Wilcoxon rank sum test; Fisher’s exact test.
+Immunosuppressed definition derived from UKHSA Influenza treatment guidance.
ICU, Intensive Care Unit; CV, Cardiovascular; COPD, Chronic obstructive pulmonary disease; CKD, Chronic kidney disease; CLD, Chronic liver disease; LDH, Lactate dehydrogenase; IL, Interleukin; TNF, Tumour necrosis factor; GMCSF, Granulocyte-macrophage colony-stimulating factor; IFN, Interferon; NEWS2, National early warning score 2; O2, administration of supplementary oxygen; CXR, Chest x-ray; CT, Computational tomography; NIV, Non-invasive ventilation; IV, Invasive ventilation; ECMO, Extracorporeal membrane oxygenation.