Table 1

Description of colorectal cancer cases and matched controls

Baseline characteristicCasesControlsp Value
Colorectal12381238
Colon779779
 Proximal322322
 Distal381381
 Unspecified7676
Rectum459459
Number of men618618
Number of women620620
Age*
 At recruitment59.0 (53.7–63.0)59.1 (53.7–63.0)0.99
 At blood donation59.1 (53.8–63.1)59.2 (53.9–63.0)0.95
 At end of follow-up62.5 (57.8–67.0)
Years of follow-up3.8 (2.1–5.5)
Anthropometrics*
 Height (cm)167.5 (161.0–175.0)167.4 (159.9–174.5)0.07
 Weight (kg)74.5 (65.0–84.5)72.8 (64.0–82.3)<0.01
 BMI (kg/m2)26.3 (23.8–29.1)25.8 (23.7–28.4)0.02
Smoking duration*13.0 (0.0–33.0)10.0 (0.0–32.0)0.31
Other smoking habits
 Never508 (41.0)531 (42.9)0.79
 Former smoker, time since quitting ≥20 years162 (13.1)168 (13.6)
 Former smoker, time since quitting ≥10 and <20 years123 (9.9)120 (9.7)
 Former smoker, time since quitting <10 years109 (8.8)94 (7.6)
 Smoker, cigarettes per day <15118 (9.5)120 (9.7)
 Smoker, cigarettes per day ≥15 and <2599 (8.0)104 (8.4)
 Smoker, cigarettes per day ≥2529 (2.3)29 (2.3)
 Missing/unspecified smoking status90 (7.3)72 (5.8)
Physical activity
 Inactive304 (24.6)283 (22.9)0.06
 Moderately inactive368 (29.7)343 (27.7)
 Moderately active262 (21.2)243 (19.6)
 Active232 (18.7)288 (23.3)
 Missing/unspecified72 (5.8)81 (6.5)
Highest educational level
 None60 (4.9)53 (4.3)0.06
 Primary school417 (33.7)477 (38.5)
 Technical/professional school311 (25.1)307 (24.8)
 Secondary school192 (15.5)152 (12.3)
 Longer education (including university degree)219 (17.7)220 (17.8)
 Missing/unspecified39 (3.2)29 (2.3)
Fasting status
 Not fasting599 (48.4)604 (48.8)0.99
 In between287 (23.2)284 (22.9)
 Fasting329 (26.6)329 (26.6)
 Missing23 (1.9)21 (1.7)
Menopausal status (only women)
 Premenopausal63 (10.2)64 (10.3)1.00
 Perimenopausal77 (12.4)76 (12.3)
 Postmenopausal (natural)450 (72.6)449 (72.4)
 Surgical postmenopausal30 (4.8)31 (5.0)
HRT use (only women)
 No446 (71.9)456 (73.6)0.81
 Yes150 (24.2)141 (22.7)
 Missing24 (3.9)23 (3.7)
Dietary variables*
 Fruit intake (g/day)184.3 (98.6–308.2)192.5 (108.1–315.9)0.14
 Vegetable intake (g/day)153.8 (99.0–231.4)156.2 (101.8–238.4)0.37
 Alcohol (g/day)9.0 (1.4–24.1)8.2 (1.6–21.6)0.27
 Red meat (g/day)49.0 (26.4–78.7)48.3 (25.6–76.7)0.34
 Processed meat (g/day)26.3 (13.8–43.7)25.2 (13.0–44.6)0.23
 Fish (g/day)26.3 (13.9–46.1)28.5 (13.8–49.3)0.15
 Energy from fat (kcal)711.3 (546.8–913.2)713.0 (555.6–890.7)0.96
 Energy from non-fat (kcal)1363.9 (1096.3–1661.4)1329.9 (1087.8–1618.0)0.16
 Total fibre intake (g/day)21.8 (17.2–27.4)22.4 (17.8–27.3)0.11
 Total fat intake (g/day)79.0 (60.8–101.5)79.2 (61.7–99.0)0.96
Other biomarkers*
 CRP (mg/l)2.8 (1.1–5.1)2.3 (1.1–4.5)<0.01
 C peptide (ng/ml)4.0 (2.9–6.1)3.9 (2.7–5.8)0.08
 HbA1c (%)5.7 (5.5–6.0)5.7 (5.5–6.0)0.05
 ROM (U/ml)396.0 (347.0–444.0)380.0 (332.0–426.0)<0.01
  • * Values are median (IQR).

  • Values are n (%).

  • Calculated using Wilcoxon two-sample test for continuous variables and χ2 tests for categorical variables.

  • BMI, body mass index; CRP, C reactive protein; HbA1c, glycosylated haemoglobin; HRT, postmenopausal hormone therapy; ROM, reactive oxygen metabolites.