Baseline clinical characteristics and presentation
| Overall | hs-TnI −/BNP − | hs-TnI −/BNP + | hs-TnI +/BNP − | hs-TnI +/BNP + | P value | |
| No. of patients | 397 | 208 | 59 | 40 | 90 | |
| Age | 66.7 (55.0–75.7) | 59.4 (48.8–68.5) | 70.5 (60.7–81.1) | 67.5 (53.3–75.6) | 75.8 (70.7–83.3) | <0.001 |
| Men | 267/397 (67.3) | 136/208 (65.4) | 39/59 (66.1) | 33/40 (82.5) | 59/90 (65.6) | 0.195 |
| Cardiovascular risk factors | ||||||
| BMI, kg/m2 | 26.2 (24.2–30.0) | 26.7 (24.3–30.3) | 25.99 (23.1–28.2) | 27.0 (24.9–34.4) | 25.1 (23.7–28.2) | 0.244 |
| Active smoking | 36/396 (9.1) | 9/207 (4.4) | 9/59 (15.3) | 2/40 (5.0) | 16/90 (17.8) | 0.001 |
| Dyslipidaemia | 100/395 (25.3) | 30/207 (14.5) | 15/58 (25.9) | 11/40 (27.5) | 44/90 (48.9) | <0.001 |
| Hypertension | 224/395 (56.7) | 85/207 (41.1) | 40/58 (69.0) | 27/40 (67.5) | 72/90 (80.0) | <0.001 |
| Diabetes mellitus | 97/395 (24.6) | 36/207 (17.4) | 20/58 (34.5) | 11/40 (27.5) | 30/90 (33.3) | 0.005 |
| Insulin-dependent diabetes mellitus | 38/395 (9.6) | 11/207 (5.3) | 6/58 (10.3) | 6/40 (15.0) | 15/90 (16.7) | 0.009 |
| Cardiovascular history | ||||||
| Prior myocardial infarction | 33/395 (8.4) | 5/207 (2.4) | 7/58 (12.1) | 3/40 (7.5) | 18/90 (20.0) | <0.001 |
| LVEF <50% | 18/395 (4.6) | 2/207 (1.0) | 4/58 (6.9) | 2/40 (5.0) | 10/90 (11.1) | 0.001 |
| History of atrial fibrillation | 39/395 (9.9) | 12/207 (5.8) | 9/58 (15.5) | 2/40 (5.0) | 16/90 (17.8) | 0.004 |
| Prior cerebrovascular events | 31/395 (7.9) | 6/207 (2.9) | 2/58 (3.5) | 6/40 (15.0) | 17/90 (18.9) | <0.001 |
| Comorbidities | ||||||
| CKD | 85/322 (26.4) | 15/169 (8.9) | 23/51 (45.1) | 10/34 (29.4) | 37/68 (54.4) | <0.001 |
| COPD | 35/395 (8.9) | 14/207 (6.8) | 7/58 (12.1) | 0/40 (0.0) | 14/90 (15.6) | 0.013 |
| Liver disease | 18/395 (4.6) | 5/207 (2.4) | 4/58 (6.9) | 2/40 (5.0) | 7/90 (7.8) | 0.108 |
| Malignancy | 62/395 (15.7) | 24/207 (11.6) | 12/58 (20.7) | 5/40 (12.5) | 21/90 (23.3) | 0.057 |
| Autoimmune disease | 16/395 (4.1) | 6/207 (2.9) | 2/58 (3.5) | 3/40 (7.5) | 5/90 (5.6) | 0.380 |
| Clinical presentation | ||||||
| Heart rate >100 bpm | 72/397 (18.1) | 27/208 (13.0) | 13/59 (22.0) | 9/40 (22.5) | 23/90 (25.6) | 0.042 |
| Respiratory rate >20 bpm | 142/397 (35.8) | 63/208 (30.3) | 22/59 (37.3) | 14/40 (35.0) | 43/90 (47.8) | 0.039 |
| Body temperature >37°C | 181/397 (45.6) | 94/208 (45.2) | 27/59 (45.8) | 15/40 (37.5) | 45/90 (50.0) | 0.620 |
| SBP <100 mm Hg | 15/397 (3.8) | 8/208 (3.8) | 3/59 (5.1) | 1/40 (2.5) | 3/90 (3.3) | 0.931 |
| First O2 saturation <94% | ||||||
| Without O2 | 58/268 (21.6) | 30/168 (17.9) | 14/35 (40.0) | 4/23 (17.4) | 10/42 (23.8) | 0.166 |
| With O2 therapy | 69/104 (66.4) | 29/37 (78.4) | 9/16 (56.3) | 19/14 (71.4) | 21/37 (56.7) | 0.200 |
BMI, body mass index; BNP, B-type natriuretic peptide; CKD, chronic kidney disease; COPD, chronic obstructive pulmonary disease; hs-TnI, high-sensitivity troponin I; LVEF, left ventricular ejection fraction; SBP, systolic blood pressure.