Table 1. Description of participants.
| Cases | Controls | ||
| (n = 246) | (n = 480) | P value | |
| Demographics | |||
| Age (years) | |||
| Mean (SD) | 63 (7.2) | 58 (4.9) | <0.001 |
| Median (min–max) | 63 (50–75) | 58 (50–69) | |
| Sex, n (%) | |||
| Male | 146 (60.1) | 314 (65.4) | 0.159 |
| Female | 97 (39.9) | 166 (34.6) | |
| Lifestyle behavior | |||
| BMI (Kg/m2) | |||
| Mean (SD) | 28 (4.2) | 28 (3.6) | 0.510 |
| Median (min–max) | 28 (20–43) | 27 (20–41) | |
| BMI category, n (%)# | |||
| <25 | 34 (23.4) | 48 (23.2) | 0.955 |
| ≥25 | 111 (76.6) | 159 (76.8) | |
| Smoking status, n (%) | |||
| Never-smokers | 92 (62.6) | 219 (60.3) | 0.636 |
| Ever-smokers* | 55 (37.4) | 144 (39.7) | |
| Tumor characteristics | |||
| Tumor location, n (%) | |||
| Rectum | 127 (52.3) | – | |
| Colon | 116 (47.7) | – | |
| Stage, n (%) | |||
| I–II | 121 (52.6) | – | |
| III–IV | 109 (47.4) | – | |
| Grade, n (%) | |||
| Low grade | 135 (95.7) | – | |
| High grade | 6 (2.4) | – | |
| Synchronous tumors, n (%) | |||
| Yes | 14 (5.5) | – | |
| No | 224 (88.2) | – |
BMI, body mass index;
#
Categorization based on the cutoff defined by the world Health Organization for overweight people;
*Never- and former-smokers pooled together; For synchronous tumors the most advanced lesions was the one considered in the tumors’ characterization.