Table 1.
Characteristics of cases and controls
| Variables | Cases | Controls | p-values | ||
|---|---|---|---|---|---|
| Total | 481 | 962 | |||
| Sex | 1.00 | ||||
| Male | 300 | 62.4% | 600 | 62.4% | |
| Female | 181 | 37.6% | 362 | 37.6% | |
| Age (years) | 0.803 | ||||
| < 40 | 20 | 4.2% | 39 | 4.1% | |
| 40-49 | 50 | 10.4% | 105 | 10.9% | |
| 50-59 | 169 | 35.1% | 328 | 34.1% | |
| 60-69 | 164 | 34.1% | 353 | 36.7% | |
| 70- | 78 | 16.2% | 137 | 14.2% | |
| Mean age (SD) | 60 (10.2) | 60 (9.86) | |||
| Site of Cancer | |||||
| Colon | 245 | 50.9% | |||
| Rectum | 236 | 49.1% | |||
| Smoking | 0.102 | ||||
| None | 215 | 44.7% | 493 | 51.3% | |
| Low-moderate (< 20 pack-years) | 59 | 12.3% | 116 | 12.1% | |
| Heavy (≥ 20 pack-years) | 203 | 42.2% | 345 | 35.9% | |
| Unknown | 4 | 0.8% | 8 | 0.8% | |
| Drinking | 0.695 | ||||
| None | 190 | 39.5% | 383 | 39.8% | |
| Low (< 5 g ethanl/day) | 64 | 13.3% | 125 | 13.0% | |
| Moderate (5≤ and < 23 g ethanol/day) | 85 | 17.7% | 196 | 20.4% | |
| High (≥ 23 g ethanol/day) | 135 | 28.1% | 243 | 25.3% | |
| Unknown | 7 | 1.5% | 15 | 1.6% | |
| Daily folate consumption | 0.857 | ||||
| T1 (≤ 262.0 μg/day) | 153 | 31.8% | 286 | 29.7% | |
| T2 (≤ 346.6 μg/day) | 158 | 32.9% | 318 | 33.1% | |
| T3 (> 346.6 μg/day) | 162 | 33.7% | 341 | 35.5% | |
| Unknown | 8 | 1.7% | 17 | 1.8% | |
| Body-Mass Index (BMI) kg/m2 | 0.923 | ||||
| < 22.5 | 206 | 42.8% | 397 | 41.3% | |
| 22.5 ≤ and < 25 | 157 | 32.6% | 314 | 32.6% | |
| 25 ≤ and < 27.5 | 73 | 15.2% | 162 | 16.8% | |
| ≥ 27.5 | 41 | 8.5% | 79 | 8.2% | |
| Unknown | 4 | 0.8% | 10 | 1.0% | |
| Family history of colorectal cancer in the first degree relatives | 0.014 | ||||
| No | 453 | 94.2% | 932 | 96.9% | |
| Yes | 28 | 5.8% | 30 | 3.1% | |
| Average recreational exercise | 0.329 | ||||
| None | 192 | 39.9% | 349 | 36.3% | |
| < 0.5 hour/day | 194 | 40.3% | 398 | 41.4% | |
| 0.5 ≤ hour/day | 95 | 19.8% | 215 | 22.4% | |