Table 1. Demographics and clinical presentation, by Wave 1 and Wave 2 and period in between two waves.
| Wave 1 | Period between Waves | Wave 2 | p-value* | |
|---|---|---|---|---|
| Number of patients | N = 1,215 | N = 120 | N = 2,614 | |
| Age at admission: mean (SD) | 68 (17) | 66 (20) | 64 (18) | <0.001 |
| Sex, Male, n (%) | 723 (59.5%) | 55 (45.8%) | 1,430 (54.7%) | 0.005 |
| BAME ethnicity, n (%) | 416 (34.2%) | 42 (35.0%) | 700 (26.8%) | <0.001 |
| Diabetes, n (%) | 518 (42.6%) | 45 (37.5%) | 636 (24.3%) | <0.001 |
| Hypertension, n (%) | 836 (68.8%) | 76 (63.3%) | 967 (37.0%) | <0.001 |
| Obese BMI >/ = 30, n (%) | 285 (27.8%) | 36 (32.4%) | 781 (35.5%) | <0.001 |
| Admission neutrophils, 10^9/L, median (IQR) | 6 (4–8) | 5 (3–8) | 5 (4–7) | <0.001 |
| Admission CRP, mg/L, median (IQR) | 86 (41–155) | 56 (27–129) | 74 (33–132) | <0.001 |
| Physiological observation score, NEWS2**, range 0–20 | 3 (2–5) | 2 (0–4) | 3 (1–5) | 0.42 |
| Abnormal chest X-ray, n (%) | 1,061 (87.8%) | 74 (61.7%) | 1,492 (69.6%) | <0.001 |
| Chest X-ray score***, median (IQR) | 3 (2–5) | 5 (3–6) | 4 (0–6) | <0.001 |
| Prescription remdesivir, n (%) | 40 (3.3%) | 19 (15.8%) | 837 (32.0%) | <0.001 |
| Prescription dexamethasone, n (%) | 18 (1.5%) | 30 (25.0%) | 1,869 (71.5%) | <0.001 |
| Time to 1st PCR+, days, median, IQR | 1 (0–1) | 1 (0–1) | 0 (0–0) | <0.001 |
| Admitted to ICU, n (%) | 194 (16.0%) | 18 (15.0%) | 429 (16.4%) | 0.88 |
| Outcome, n (%): Still admitted | 0 (0.0%) | 0 (0.0%) | 21 (0.8%) | <0.001 |
| Died | 332 (27.3%) | 18 (15.0%) | 383 (14.7%) | |
| Discharged | 883 (72.7%) | 102 (85.0%) | 2,210 (84.5%) |
* Comparison only between Wave 1 and Wave 2.
** National Early Warning Score (NEWS) 2 is based on a simple aggregate scoring system of 6 physiological parameters: respiration rate, oxygen saturation, systolic blood pressure, pulse rate, level of consciousness or new confusion, temperature. A score is allocated to each parameter as they are measured, with the magnitude of the score reflecting how extremely the parameter varies from the norm. The score is then aggregated and uplifted by 2 points for people requiring supplemental oxygen to maintain their recommended oxygen saturation.
*** Chest radiographs were assessed using an adapted radiographic assessment of lung oedema (RALE) score for COVID-19, as introduced by Wong et al. The severity score attributes a number between 0–4 to each lung depending on extent of consolidation or ground glass opacities (0 = no involvement, 1 = <25%, 2 = 25–49%, 3 = 50–75%, 4 = >75% involvement). Values for each lung were summed to produce a final score ranging from 0–8. Correlation between lungs was high (r = 0.65; κ = 0.44). The first 200 radiographs were assessed by two independent clinicians. Inter-rater concordance demonstrated high agreement (90.5%). Single reading was undertaken for remaining radiographs.