| Variable | % (no.)* | p value | |||
|---|---|---|---|---|---|
| All patients n = 369 | Centre 1 n = 174 | Centre 2 n = 114 | Centre 3 n = 81 | ||
| Hypertension | 56 (205) | 51 (88) | 66 (75) | 52 (42) | 0.03 |
| Diabetes mellitus | 31 (115) | 29 (51) | 31 (35) | 36 (29) | 0.6 |
| Coronary artery disease | 31 (113) | 30 (52) | 38 (43) | 22 (18) | 0.07 |
| Chronic obstructive pulmonary disease | 25 (94) | 28 (49) | 21 (24) | 26 (21) | 0.4 |
| Peripheral vascular disease | 19 (71) | 22 (38) | 24 (27) | 7 (6) | 0.01 |
| Immunosuppression | 18 (68) | 17 (30) | 11 (13) | 31 (25) | 0.002 |
| Chronic renal failure | 18 (66) | 14 (25) | 13 (15) | 32 (26) | 0.001 |
| Heart failure | 18 (65) | 15 (26) | 21 (24) | 19 (15) | 0.4 |
| Neoplasia | 17 (64) | 21 (36) | 8 (9) | 23 (19) | 0.01 |
| Cirrhosis | 8 (29) | 5 (9) | 11 (12) | 10 (8) | 0.2 |
| Asthma | 4 (16) | 2 (3) | 3 (3) | 12 (10) | 0.001 |
| No. of comorbidities per patient, median (IQR) | 3 (1 to 4) | 2 (1 to 4) | 3 (1 to 4) | 3 (2 to 4) | 1.0 |
| Patients with no chronic comorbidity | 10 (38) | 12 (21) | 11 (13) | 5 (4) | 0.2 |
| Patients with ≥ 1 chronic comorbidities | 90 (331) | 88 (153) | 89 (101) | 95 (77) | 0.2 |
| Patients with ≥ 2 chronic comorbidities | 71 (263) | 67 (117) | 70 (80) | 81 (66) | 0.06 |
Note: IQR = interquartile range. *Unless stated otherwise.