Table 1.
Characteristics of study population.
| Total | Controls | Cases | |
|---|---|---|---|
| All sexes | |||
| N = 3182 | N = 1591 | N = 1591 | |
| Age at recruitment (years) [mean, sd] | 56.8 (7.5) | 56.7 (7.5) | 56.8 (7.5) |
| Age at recruitment (years) | |||
| <55 | 1218 (38%) | 608 (38%) | 610 (38%) |
| ≥55 | 1964 (62%) | 983 (62%) | 981 (62%) |
| Age at blood collection (years) [mean, sd] | 56.9 (7.5) | 56.9 (7.5) | 57.0 (7.5) |
| Follow-up time after blood collection (years) [median, IQR] | – | – | 7.3 (4.2–11.3) |
| Colorectal cancer subsite | |||
| Colon | – | – | 1362 (86%) |
| Rectal | – | – | 229 (14%) |
| Sex | |||
| Men | 1442 (45%) | 721 (45%) | 721 (45%) |
| Women | 1740 (55%) | 870 (55%) | 870 (55%) |
| Highest education level | |||
| None/primary school | 1400 (44%) | 721 (45%) | 679 (43%) |
| Technical/professional/secondary school | 1163 (37%) | 559 (35%) | 604 (38%) |
| Longer education including university | 511 (16%) | 264 (17%) | 247 (16%) |
| Not specified/missing | 108 (3%) | 47 (3%) | 61 (4%) |
| Cambridge physical activity index | |||
| Inactive | 858 (27%) | 402 (25%) | 456 (29%) |
| Moderately inactive | 1076 (34%) | 541 (34%) | 535 (34%) |
| Moderately active | 618 (19%) | 310 (19%) | 308 (19%) |
| Active | 584 (18%) | 315 (20%) | 269 (17%) |
| Missing | 46 (1%) | 23 (1%) | 23 (1%) |
| Smoking status | |||
| Never | 1428 (45%) | 753 (47%) | 675 (42%) |
| Former | 991 (31%) | 476 (30%) | 515 (32%) |
| Current smoker | 731 (23%) | 346 (22%) | 385 (24%) |
| Unknown | 32 (1%) | 16 (1%) | 16 (1%) |
| Height (cm) [mean, sd] | 165.9 (9.3) | 165.6 (9.3) | 166.2 (9.3) |
| Body Mass Index (kg/m2) [mean, sd] | 26.7 (4.1) | 26.4 (3.9) | 27.0 (4.4) |
| Body Mass Index (kg/m2) | |||
| <25 | 1161 (36%) | 608 (38%) | 553 (35%) |
| ≥25 | 2021 (64%) | 983 (62%) | 1038 (65%) |
| Alcohol intake at recruitment (g/day) [median, IQR] | 8.0 (1.0–23.9) | 8.1 (1.1–23.0) | 7.8 (0.8–24.5) |
| Total energy intake (kcal/day) [mean, sd] | 2168.1 (674.4) | 2174.6 (643.5) | 2161.7 (704.3) |
| Meat intake (red and processed) (g/day) [median, IQR] | 77.2 (49.4–110.7) | 78.8 (50.4–110.7) | 74.9 (48.7–110.8) |
| Dietary fibre intake (g/day) [mean, sd] | 23.4 (8.1) | 23.7 (8.2) | 23.2 (8.0) |
| Dairy intake (g/day) [median, IQR] | 270.6 (150.4–432.1) | 281.3 (160.6–444.7) | 256.1 (138.2–420.0) |
| Women only | |||
| N = 1740 | N = 870 | N = 870 | |
| Menopausal status | |||
| Premenopausal | 291 (17%) | 148 (17%) | 143 (16%) |
| Postmenopausal | 1168 (67%) | 586 (67%) | 582 (67%) |
| Perimenopausal/unknown menopausal status | 181 (10%) | 90 (10%) | 91 (10%) |
| Surgical postmenopausal | 100 (6%) | 46 (5%) | 54 (6%) |
| Ever use of hormones for menopause | |||
| Never | 1297 (75%) | 646 (74%) | 651 (75%) |
| Yes | 387 (22%) | 194 (22%) | 193 (22%) |
| Missing | 56 (3%) | 30 (3%) | 26 (3%) |
| Ever use of oral contraceptives | |||
| Never | 1018 (59%) | 498 (57%) | 520 (60%) |
| Yes | 701 (40%) | 365 (42%) | 336 (39%) |
| Missing | 21 (1%) | 7 (1%) | 14 (2%) |
Number and percentage reported unless stated otherwise; IQR, interquartile range; sd, standard deviation.