Table 1.
Characteristics of gastrointestinal cancer cases and controls*. Values are numbers (percentages) unless stated otherwise
| Characteristics | Oesophageal cancer | Gastric cancer | Colorectal cancer | |||||
|---|---|---|---|---|---|---|---|---|
| Cases (n=2954) | Controls (n=14 721) | Cases (n=2018) | Controls (n=10 007) | Cases (n=10 641) | Controls (n=53 022) | |||
| Mean years of observation | 7.7 | 7.7 | 7.5 | 7.5 | 7.5 | 7.5 | ||
| Female sex | 1074 (36) | 5345 (36) | 770 (38) | 3822 (38) | 4900 (46) | 24 450 (46) | ||
| Age (years) at index date: | ||||||||
| 40-59 | 489 (17) | 2446 (17) | 194 (10) | 965 (10) | 1764 (17) | 8820 (17) | ||
| 60-79 | 1706 (58) | 8523 (58) | 1163 (58) | 5818 (58) | 6162 (58) | 30 807 (58) | ||
| ≥80 | 759 (25) | 3752 (25) | 661 (33) | 3224 (32) | 2715 (26) | 13 395 (25) | ||
| Smoking status: | ||||||||
| Never | 1208 (41) | 7164 (49) | 897 (44) | 4937 (49) | 5356 (50) | 26 825 (51) | ||
| Past | 680 (23) | 2970 (20) | 494 (25) | 1958 (20) | 2409 (23) | 10 464 (20) | ||
| Current | 729 (25) | 2405 (16) | 396 (20) | 1544 (15) | 1665 (16) | 8123 (15) | ||
| Missing | 337 (11) | 2182 (15) | 231 (11) | 1568 (16) | 1211 (11) | 7610 (14) | ||
| Alcohol intake: | ||||||||
| Non-drinker | 466 (16) | 2256 (15) | 389 (19) | 1664 (17) | 1649 (15) | 8277 (16) | ||
| Drinker | 1893 (64) | 8909 (61) | 1206 (60) | 5777 (58) | 6777 (64) | 31 958 (60) | ||
| Missing | 595 (20) | 3556 (24) | 423 (21) | 2556 (26) | 2215 (21) | 12 757 (24) | ||
| Body mass index (kg/m2): | ||||||||
| <25.0 | 811 (27) | 3883 (26) | 548 (27) | 2631 (26) | 2840 (27) | 14 573 (27) | ||
| 25.0-29.9 | 864 (29) | 4459 (30) | 567 (28) | 2873 (29) | 3203 (30) | 15 694 (30) | ||
| ≥30.0 | 403 (14) | 1906 (13) | 258 (13) | 1203 (12) | 1472 (14) | 6808 (13) | ||
| Missing | 876 (30) | 4473 (30) | 645 (32) | 3300 (33) | 3126 (29) | 15 947 (30) | ||
| Prescribed oral bisphosphonate | 90 (3.0) | 345 (2.3) | 49 (2.4) | 270 (2.7) | 276 (2.6) | 1555 (2.9) | ||
*Five controls matched to each case by age at diagnosis of case (index date) to within 2 years, sex, general practice, and observation period in General Practice Research Database.