Table 1 Subjects’ characteristics by the presence of cold injuries unit: n (%)
|  | With cold injuries (n = 3154) | Without cold injuries (n = 532,032) | p-valuea |
|---|---|---|---|
Age (year) | |||
 20–29 | 727 (23.05) | 110,472 (20.76) | 0.0098 |
 30–39 | 761 (24.13) | 135,853 (25.53) |  |
 40–49 | 790 (25.05) | 133,390 (25.07) |  |
 50–59 | 463 (14.68) | 79,013 (14.85) |  |
 60–69 | 320 (10.15) | 53,174 (9.99) |  |
 70–79 | 84 (2.66) | 17,557 (3.30) |  |
 80- | 9 (0.29) | 2573 (0.48) |  |
Sex | |||
 Male | 1289 (40.87) | 268,627 (50.49) | < 0.0001 |
 Female | 1865 (59.13) | 263,405 (49.51) |  |
Household income | |||
  ≤ 25% | 1072 (33.99) | 162,062 (30.46) | < 0.0001 |
 26–50% | 678 (21.50) | 117,951 (22.17) |  |
 51–74% | 708 (22.45) | 121,472 (22.83) |  |
  ≥ 75% | 696 (22.07) | 130,547 (24.54) |  |
Smoking status | |||
 Current smoker | 622 (19.72) | 144,901 (27.24) | < 0.0001 |
 Past smoker | 257 (8.15) | 48,550 (9.13) |  |
 Never smoker | 2275 (72.13) | 338,581 (63.64) |  |
Alcohol drinking | |||
 No | 1784 (56.56) | 277,416 (52.14) | < 0.0001 |
 Yes | 1370 (43.44) | 254,616 (47.86) |  |
Regular exercise | |||
 No | 1868 (59.23) | 298,930 (56.19) | 0.0006 |
 Yes | 1286 (40.77) | 233,102 (43.81) |  |
BMI classificationb | |||
 Underweight | 196 (6.21) | 21,888 (4.11) | < 0.0001 |
 Normal weight | 2262 (71.72) | 339,002 (63.72) |  |
 Overweight | 642 (20.36) | 151,634 (28.50) |  |
 Obese | 54 (1.71) | 19,508 (3.67) |  |
High blood pressurec | |||
 No | 2874 (91.12) | 463,475 (87.11) | < 0.0001 |
 Yes | 280 (8.88) | 68,557 (12.89) |  |
Hyperglycemiad | |||
 No | 3004 (95.24) | 498,660 (93.73) | 0.0005 |
 Yes | 150 (4.76) | 33,372 (6.27) |  |