Baseline characteristics of patients by site
| Internal validation n=880 | External validation n=845 | |||||||
|---|---|---|---|---|---|---|---|---|
| Site A n=459 | Site B n=421 | Site C n=307 | Site D n=271 | Site E n=171 | Site F n=96 | All sites N=1725 | p Value | |
| Recruitment period | Jan 12-May 13 | Jan 12-May 13 | Aug 13-May 14 | Jul 13-Apr 14 | Apr 13-Feb 14 | Feb 14-Apr 14 | Jan 12-May 14 | N/A |
| Recruitment/day | 0.89 | 0.82 | 1.07 | 0.89 | 0.58 | 1.12 | 0.86 | N/A |
| Died inhospital, % | 9.8 | 7.8 | 7.5 | 6.6 | 4.7 | 5.2 | 7.7 | 0.27 |
| DECAF 0–1, % | 44.4 | 46.6 | 47.6 | 34.3 | 44.4 | 61.5 | 44.9 | 0.00018 |
| DECAF 2, % | 30.9 | 26.6 | 29.6 | 28.0 | 32.7 | 21.9 | 28.9 | 0.33 |
| DECAF 3–6, % | 24.6 | 26.8 | 22.8 | 37.6 | 22.8 | 16.7 | 26.3 | 0.00013 |
| Sociodemographics | ||||||||
| Age, years* | 73.5 (9.9) | 73.9 (10.3) | 73.5 (10.4) | 72.0 (9.8) | 72.4 (10.7) | 70.7 (11.4) | 73.1 (10.3) | 0.025 |
| Female, % | 56.4 | 58.0 | 56.4 | 40.6 | 58.5 | 53.1 | 54.3 | 0.00012 |
| Smoking pack-years, n† | 41 (30–58) | 40 (30–55) | 44 (30–60) | 40 (30–56) | 45 (30–60) | 40 (30–59) | 40 (30–59) | 0.71 |
| Current smoking, % | 38.2 | 40.9 | 39.7 | 36.2 | 36.1 | 47.4 | 39.1 | 0.41 |
| Institutional care, % | 8.9 | 5.0 | 2.9 | 2.6 | 4.1 | 5.2 | 5.2 | 0.0018 |
| Markers of disease severity | ||||||||
| eMRCD score 1–4, % | 44.7 | 49.2 | 49.5 | 35.1 | 44.4 | 68.8 | 46.4 | <0.0001 |
| eMRCD score 5a, % | 39.7 | 36.6 | 30.3 | 24.7 | 42.1 | 24.0 | 34.3 | <0.0001 |
| eMRCD score 5b, % | 15.7 | 14.3 | 20.2 | 40.2 | 13.5 | 7.3 | 19.3 | <0.0001 |
| Hospital admissions in previous year, n† | 0 (0–1) | 0 (0–1) | 1 (0–1) | 1 (0–2) | 1 (0–2) | 1.5 (0–3) | 0 (0–1) | <0.0001 |
| FEV1% predicted* | 47.8 (19.4) | 48.5 (18.5) | 44.8 (18.2) | 40.6 (14.9) | 40.5 (15.4) | 46.6 (20.4) | 45.5 (18.3) | <0.0001 |
| LTOT, % | 15.7 | 16.2 | 13.4 | 17.7 | 26.8 | 17.7 | 16.9 | 0.014 |
| Cor pulmonale, % | 5.9 | 7.4 | 10.4 | 8.5 | 8.9 | 2.1 | 7.5 | 0.052 |
| LT prednisolone, % | 8.1 | 6.7 | 5.5 | 10.0 | 9.0 | 7.3 | 7.6 | 0.38 |
| Comorbidity | ||||||||
| IHD, % | 27.5 | 32.3 | 31.9 | 27.7 | 26.6 | 27.1 | 29.4 | 0.46 |
| CVD, % | 13.3 | 12.4 | 13.1 | 13.7 | 5.9 | 11.5 | 12.3 | 0.14 |
| Diabetes, % | 11.3 | 11.9 | 15.0 | 13.0 | 14.8 | 17.7 | 13.1 | 0.40 |
| Atrial fibrillation, % | 14.8 | 20.7 | 16.9 | 17.7 | 16.4 | 14.6 | 17.2 | 0.33 |
| LVD, % | 8.1 | 9.3 | 18.2 | 10.0 | 4.7 | 3.2 | 9.9 | <0.0001 |
| Cognitive impairment, % | 5.0 | 5.0 | 6.8 | 8.5 | 3.6 | 1.0 | 5.5 | 0.049 |
| Anxiety, % | 13.9 | 13.3 | 37.6 | 20.3 | 7.1 | 9.4 | 18.1 | <0.0001 |
| Depression, % | 23.3 | 18.3 | 33.6 | 25.5 | 19.4 | 9.4 | 23.1 | <0.0001 |
| Admission clinical data | ||||||||
| Acute confusion, % | 12.9 | 12.9 | 8.7 | 8.9 | 6.6 | 6.3 | 10.6 | 0.060 |
| Respiratory rate, n* | 26.5 (6.8) | 25.7 (6.0) | 21.8 (4.5) | 24.1 (6.2) | 23.9 (6.2) | 23.5 (6.3) | 24.7 (6.3) | <0.0001 |
| Pulse rate, n* | 104.9 (21.0) | 102.8 (22.8) | 97.1 (18.3) | 102.2 (20.5) | 104.7 (21.6) | 99.7 (18.4) | 102.3 (21.0) | <0.0001 |
| sBP, mm Hg* | 136.5 (30.3) | 145.2 (26.6) | 130.8 (22.0) | 135.0 (26.5) | 134.5 (22.9) | 133.6 (24.2) | 137.1 (26.9) | <0.0001 |
| dBP, mm Hg* | 74.6 (17.0) | 80.0 (19.0) | 71.6 (15.8) | 77.2 (18.5) | 77.3 (19.6) | 73.2 (13.7) | 76.0 (17.9) | <0.0001 |
| Temperature, °C† | 36.9 (36.3–37.6) | 36.5 (36.0–37.2) | 36.8 (36.4–37.3) | 36.5 (36.0–37.1) | 36.5 (35.9–37.0) | 36.7 (36.0–37.0) | 36.7 (36.2–37.3) | <0.0001 |
| Oxygen saturation† | 92 (87–94) | 93 (88–95) | 94 (91–95) | 93 (90–95) | 93 (90–95) | 92 (91–95) | 93 (89–95) | <0.0001 |
| Pedal oedema, % | 25.8 | 21.6 | 26.8 | 27.0 | 32.7 | 5.3 | 24.9 | <0.0001 |
| BMI, kg/m2* | 25.1 (6.8) | 24.9 (6.8) | 24.5 (6.4) | 25.4 (6.4) | 24.1 (6.5) | N/A | 24.9 (6.6) | 0.28 |
| Weight loss >5%, % | 14.2 | 10.6 | 21.2 | 24.7 | 12.9 | 2.4 | 15.3 | <0.0001 |
| CXR consolidation, % | 30.5 | 34.4 | 22.8 | 30.6 | 18.7 | 19.8 | 28.3 | <0.0001 |
| Arterial blood gas values | ||||||||
| pH† | 7.42 (7.37–7.46) | 7.42 (7.37–7.46) | 7.43 (7.38–7.46) | 7.40 (7.35–7.44) | 7.45 (7.38–7.48) | 7.39 (7.35–7.43) | 7.42 (7.37–7.46) | <0.0001 |
| PaO2, kPa† | 8.0 (6.9–9.3) | 8.0 (6.9–9.3) | 8.6 (7.7–9.8) | 8.4 (7.3–10) | 9.4 (7.8–9.4) | 8.3 (7.5–9.4) | 8.3 (7.2–9.7) | <0.0001 |
| PaCO2, kPa† | 5.6 (4.8–7.1) | 5.7 (4.8–7.3) | 5.2 (4.4–6.2) | 6.1 (5.3–7.5) | 5.6 (4.8–7.6) | 6.1 (5.1–7.1) | 5.7 (4.8–7.1) | <0.0001 |
| HCO3, mmol/L* | 28.1 (6.0) | 28.7 (6.8) | 26.5 (5.5) | 28.7 (5.4) | 30.2 (8.9) | 27.8 (5.0) | 28.3 (6.4) | <0.0001 |
| pH <7.35, % | 17.8 | 19.2 | 15.1 | 24.3 | 17.9 | 20.8 | 18.9 | 0.19 |
Sites compared by Fisher's (proportions), ANOVA or Welch (means), or Kruskal–Wallis (median) tests.
*Mean (SD).
†Median (IQR).
BMI, body mass index; CVD, cerebrovascular disease; CXR, chest radiograph; dBP and sBP, diastolic and systolic blood pressure; HCO3, bicarbonate; IHD, ischaemic heart disease; LT, long term; LTOT, long-term oxygen therapy; LVD, left ventricular dysfunction.