Characteristics | Colon | Rectum | Overall | |||
Cases | Controls | Cases | Controls | Cases | Controls | |
N | 19 726 | 92 999 | 9254 | 44 078 | 28 980 | 1 37 077 |
Duration of follow-up* (years), median (IQR) | 8.2 (5.0–12.4) | 8.2 (5.0–12.3) | 8.0 (4.8–12.0) | 8.0 (4.8–12.0) | 8.1 (5.0–12.3) | 8.1 (4.9,12.2) |
Age (years), median (IQR) | 73 (64–79) | 72 (64–79) | 71 (62–78) | 70 (62–78) | 72 (64,79) | 72 (63,79) |
Sex | ||||||
Male | 10 465 (53.1) | 48 960 (52.6) | 5630 (60.8) | 26 688 (60.5) | 16 095 (55.5) | 75 648 (55.2) |
Female | 9261 (46.9) | 44 039 (47.4) | 3624 (39.2) | 17 390 (39.5) | 12 885 (44.5) | 61 429 (44.8) |
BMI category† | ||||||
Normal | 5561 (28.2) | 28 384 (30.5) | 2664 (28.8) | 13 132 (29.8) | 8225 (28.4) | 41 516 (30.3) |
Overweight | 7016 (35.6) | 31 397 (33.8) | 3185 (34.4) | 14 877 (33.8) | 10 201 (35.2) | 46 274 (33.8) |
Obese | 3807 (19.3) | 15 374 (16.5) | 1586 (17.1) | 7088 (16.1) | 5393 (18.6) | 22 462 (16.4) |
Missing | 3342 (16.9) | 17 844 (19.2) | 1819 (19.7) | 8981 (20.4) | 5161 (17.8) | 26 825 (19.6) |
Smoking status‡ | ||||||
Never smoker | 8268 (41.9) | 39 724 (42.7) | 3599 (38.9) | 18 327 (41.6) | 11 867 (40.9) | 58 051 (42.3) |
Current smoker (trivial-light) | 718 (3.6) | 3391 (3.6) | 367 (4.0) | 1664 (3.8) | 1085 (3.7) | 5055 (3.7) |
Current smoker (moderate) | 996 (5.0) | 5081 (5.5) | 565 (6.1) | 2485 (5.6) | 1561 (5.4) | 7566 (5.5) |
Current smoker (heavy) | 1051 (5.3) | 4887 (5.3) | 532 (5.7) | 2522 (5.7) | 1583 (5.5) | 7409 (5.4) |
Current smoker (amount unknown) | 1217 (6.2) | 5539 (6.0) | 547 (5.9) | 2569 (5.8) | 1764 (6.1) | 8108 (5.9) |
Ex-smoker | 5769 (29.2) | 24 636 (26.5) | 2691 (29.1) | 11 403 (25.9) | 8460 (29.2) | 36 039 (26.3) |
Missing | 1707 (8.7) | 9741 (10.5) | 953 (10.3) | 5108 (11.6) | 2660 (9.2) | 14 849 (10.8) |
Alcohol use§ | ||||||
Non-drinker | 1734 (8.8) | 9244 (9.9) | 758 (8.2) | 4047 (9.2) | 2492 (8.6) | 13 291 (9.7) |
Current drinker (trivial-light) | 5757 (29.2) | 26 460 (28.5) | 2623 (28.3) | 12 643 (28.7) | 8380 (28.9) | 39 103 (28.5) |
Current drinker (moderate) | 2134 (10.8) | 8835 (9.5) | 1250 (13.5) | 4674 (10.6) | 3384 (11.7) | 13 509 (9.9) |
Current drinker (heavy) | 385 (2.0) | 1297 (1.4) | 211 (2.3) | 743 (1.7) | 596 (2.1) | 2040 (1.5) |
Current drinker (amount unknown) | 5970 (30.3) | 27 920 (30.0) | 2467 (26.7) | 12 485 (28.3) | 8437 (29.1) | 40 405 (29.5) |
Ex-drinker | 350 (1.8) | 1550 (1.7) | 165 (1.8) | 701 (1.6) | 515 (1.8) | 2251 (1.6) |
Missing | 3396 (17.2) | 17 693 (19.0) | 1780 (19.2) | 8785 (19.9) | 5176 (17.9) | 26 478 (19.3) |
Diabetes history | 1796 (9.1) | 7280 (7.8) | 761 (8.2) | 3298 (7.5) | 2557 (8.8) | 10 578 (7.7) |
Chronic NSAID use¶ | 1450 (7.4) | 8443 (9.1) | 645 (7.0) | 3831 (8.7) | 2095 (7.2) | 12 274 (9.0) |
Chronic aspirin use¶ | 3934 (19.9) | 18 287 (19.7) | 1635 (17.7) | 7886 (17.9) | 5569 (19.2) | 26 173 (19.1) |
Use of colonoscopy | 773 (3.9) | 2828 (3.0) | 242 (2.6) | 1209 (2.7) | 1015 (3.5) | 4037 (2.9) |
Data are n (%) unless otherwise stated.
*Date from registration to date of colorectal cancer diagnosis.
†Normal: 18.5–24.9, overweight: 25.0–29.9, obese: ≥30.0.
‡Trivial, light, moderate or heavy current smoking were assigned when either the general practitioner had recorded a Read code with one of these terms, or when the units per day were recorded as 0-1 (trivial), 1–9 (light), 10–19 (moderate), ≥20 (heavy).
§ Trivial, light, moderate, or heavy current drinking were assigned when either the general practitioner had recorded a Read code with one of these terms, or when the units per day were recorded as 0–1 (trivial), 1–2 (light), 3–6 (moderate), ≥ 7 (heavy).
¶Cumulative days prescribed for ≥ 365 days.
BMI, body mass index; NSAID, non-steroidal anti-inflammatory drug.