Table 1 Baseline characteristics of the study population according to their rewarming rate category
|  | All patients | Rewarming rate (°C/h) | P values* | ||||
|---|---|---|---|---|---|---|---|
(≥2.0) | (1.5–< 2.0) | (1.0–< 1.5) | (0.5–< 1.0) | (< 0.5) | |||
n = 481 | n = 57 | n = 36 | n = 104 | n = 175 | n = 109 | ||
Men | 243 (50.5) | 25 (43.9) | 14 (38.9) | 56 (53.8) | 93 (53.1) | 55 (50.5) | 0.424 |
Age, y, median (IQR) | 79 (67–87) | 71 (64–81)a, b | 77 (68–85) | 76 (64–87) | 82 (70–87)a | 81 (72–89)b | 0.002 |
Age category | |||||||
 Adults aged 18–64 years | 101 (21.0) | 15 (26.3) | 8 (22.2) | 27 (26.0) | 35 (20.0) | 16 (14.7) | 0.240 |
 Young-elderly aged 65–74 years | 79 (16.4) | 18 (31.6)a | 7 (19.4) | 18 (17.3) | 20 (11.4)a | 16 (14.7) | 0.014 |
 Elderly-elderly aged ≥75 years | 301 (62.6) | 24 (42.1)a, b | 21 (58.3) | 59 (56.7) | 120 (68.6)a | 77 (70.6)b | 0.002 |
Activity of daily living | |||||||
 Independent | 335 (70.0) | 49 (86.0)a | 30 (83.3)b | 74 (71.2) | 121 (68.4) | 61 (56.0)a, b | < 0.001 |
 Need for some assistance | 114 (23.7) | 8 (14.0) | 5 (13.9) | 28 (26.9) | 44 (25.3) | 29 (26.6) | 0.183 |
 Need for total assistance | 31 (6.4) | 0 (0.0)a | 1 (2.8) | 2 (1.9)b | 10 (6.3)c | 18 (16.5)a, b, c | < 0.001 |
 Unknown | 1 (0.21) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (0.9) |  |
Residence | |||||||
 Home | 432 (89.8) | 53 (93.0) | 34 (94.4) | 101 (97.1)a | 156 (89.1) | 88 (80.7)a | 0.002 |
  Living alone | 193 (40.1) | 17 (29.8) | 19 (52.8) | 51 (49.0)a | 75 (42.9) | 31 (28.4)a | 0.004 |
  Living not alone | 239 (49.7) | 36 (63.2) | 15 (41.7) | 50 (48.1) | 81 (46.3) | 57 (52.3) | 0.180 |
 Nursing home | 30 (6.2) | 0 (0.0)a | 1 (2.8) | 1 (1.0)b | 11 (6.3) | 17 (15.6)a, b | < 0.001 |
 Homelessness | 4 (0.8) | 0 (0.0) | 1 (2.8) | 0 (0.0) | 2 (1.1) | 1 (0.9) | 0.496 |
 Unknown | 15 (3.1) | 4 (7.0) | 0 (0.0) | 2 (1.9) | 6 (3.4) | 3 (2.8) |  |
Location | |||||||
 Indoor | 375 (78.0) | 36 (63.2)a, b | 27 (75.0) | 68 (65.4)c, d | 150 (85.7)a, c | 94 (86.2)b, d | < 0.001 |
 Outdoor | 106 (22.0) | 21 (36.8)a, b | 9 (25.0) | 36 (34.6)c, d | 25 (14.3)a, c | 15 (13.8)b, d | < 0.001 |
Mode of arrival | |||||||
 Ambulance | 453 (94.2) | 55 (96.5) | 35 (97.2) | 101 (97.1) | 166 (94.9) | 96 (88.1) | 0.065 |
 Walk-in | 28 (5.8) | 2 (3.5) | 1 (2.8) | 3 (2.9) | 9 (5.1) | 13 (11.9) | 0.065 |
Past medical history | |||||||
 Cardiovascular disease | 213 (44.3) | 27 (47.4) | 13 (36.1) | 37 (35.6) | 77 (44.0) | 59 (54.1) | 0.070 |
 Neurological disease | 86 (17.9) | 7 (12.3) | 4 (11.1) | 21 (20.2) | 31 (17.7) | 23 (21.1) | 0.507 |
 Endocrine disease | 116 (24.2) | 16 (28.1) | 8 (22.2) | 18 (17.3) | 44 (25.1) | 30 (27.5) | 0.391 |
 Psychiatric disease | 110 (22.9) | 18 (31.6) | 11 (30.6) | 24 (23.1) | 37 (21.1) | 20 (18.3) | 0.261 |
 Malignant disease | 50 (10.4) | 7 (12.3) | 3 (8.3) | 9 (8.7) | 23 (13.1) | 8 (7.3) | 0.546 |
 Dementia | 99 (20.6) | 5 (8.8) | 7 (19.4) | 20 (19.2) | 39 (22.3) | 28 (25.7) | 0.111 |
 Other | 88 (18.7) | 7 (12.3) | 6 (16.7) | 19 (18.3) | 35 (20.0) | 21 (19.3) | 0.784 |
 Unknown | 7 (1.46) | 1 (1.8) | 0 (0.0) | 1 (1.0) | 3 (1.7) | 2 (1.8) | 1.000 |
Number of past medical history | |||||||
 None | 118 (24.5) | 13 (22.8) | 11 (30.6) | 28 (26.9) | 47 (26.9) | 19 (17.4) | 0.308 |
 One | 152 (31.6) | 18 (31.6) | 11 (30.6) | 37 (35.6) | 50 (28.6) | 36 (33.0) | 0.803 |
 Multiple | 211 (43.9) | 26 (45.6) | 14 (38.9) | 39 (37.5) | 78 (44.6) | 54 (49.5) | 0.464 |