Table 1.
Baseline characteristics of UK Biobank participants by inflammatory bowel disease status at baseline assessmenta (n=502,369)
| IBD | |||||
|---|---|---|---|---|---|
| Characteristics | Total | Yes (N=5,789) | No (N=496,624) | UC (N=4,166) | CD (N=2,112) |
| Age at assessment, years, mean ± SD | 56.5 ± 8.1 | 57.3 ± 7.9 | 56.5 ± 8.1 | 57.6 ± 7.8 | 56.6 ± 8.0 |
| Townsend deprivation index, mean ± SD | −1.3 ± 3.1 | −1.3 ± 3.1 | −1.3 ± 3.1 | −1.31 ± 3.0 | −1.1 ± 3.2 |
| Sex, n (%) | |||||
| Male | 229,068 (45.6) | 2,752 (47.5) | 226,316 (45.6) | 2,050 (49.1) | 944 (44.6) |
| Female | 273,301 (54.0) | 3,047 (52.5) | 270,254 (54.4) | 2,124 (50.9) | 1,171 (55.4) |
| Race, n (%) | |||||
| Asian | 11,452 (2.3) | 125 (2.2) | 11,327 (2.3) | 98 (2.4) | 41 (1.9) |
| Black | 8,058 (1.6) | 38 (0.7) | 8,020 (1.6) | 26 (0.6) | 18 (0.9) |
| Mixed race | 2,953 (0.6) | 19 (0.3) | 2,934 (0.6) | 16 (0.4) | <5 (0.1) |
| Other races | 4,555 (0.9) | 34 (0.6) | 4,521 (0.9) | 28 (0.7) | 11 (0.5) |
| White | 472,573 (94.1) | 5,552 (95.7) | 467,021 (94.1) | 3,981 (95.4) | 2,032 (96.1) |
| Assessment center, n (%) | |||||
| England | 445,728 (88.7) | 5,042 (87.0) | 440,686 (88.8) | 3,625 (86.9) | 1,831 (86.6) |
| Scotland | 35,837 (7.1) | 488 (8.4) | 35,349 (7.1) | 359 (8.6) | 179 (8.5) |
| Wales | 20,804 (4.1) | 269 (4.6) | 20,535 (4.1) | 190 (4.6) | 105 (5.0) |
| BMI, kg/m 2 , n (%) | |||||
| <18.5 | 2,626 (0.5) | 45 (0.8) | 2,581 (0.5) | 22 (0.5) | 28 (1.3) |
| 18.5 to <25.0 | 162,352 (32.3) | 1,955 (33.7) | 160,397 (32.3) | 1,351 (32.5) | 750 (35.5) |
| 25.0 to <30.0 | 212,062 (42.2) | 2,485 (42.9) | 209,577 (42.2) | 1,808 (43.3) | 898 (42.5) |
| 30.0 to <35.0 | 87,534 (17.4) | 929 (16.0) | 86,605 (17.4) | 697 (16.7) | 297 (14.0) |
| ≥35.0 | 34,688 (6.9) | 344 (5.9) | 34,344 (6.9) | 257 (6.2) | 130 (6.2) |
| Overall health rating, n (%) | |||||
| Excellent | 81,833 (16.3) | 396 (6.8) | 81,437 (16.4) | 303 (7.3) | 107 (5.1) |
| Good | 288,948 (57.5) | 2,699 (46.5) | 286,249 (57.7) | 2,032 (48.7) | 855 (40.4) |
| Fair | 105,333 (21.0) | 1,961 (33.8) | 103,372 (20.8) | 1,357 (32.5) | 788 (37.3) |
| Poor | 22,768 (4.5) | 706 (12.2) | 22,062 (4.4) | 453 (10.9) | 349 (16.5) |
| Smoking, n (%) | |||||
| Never | 273,449 (54.4) | 2,727 (47.0) | 270,722 (54.5) | 2,015 (48.3) | 944 (44.6) |
| Former | 173,009 (34.4) | 2,482 (42.8) | 170,527 (34.3) | 1,836 (44.0) | 850 (40.2) |
| Current | 52,964 (10.5) | 562 (9.7) | 52,399 (10.6) | 302 (7.2) | 311 (14.7) |
| Alcohol drinking, n (%) | |||||
| Never | 22,379 (4.5) | 293 (5.1) | 22,086 (4.5) | 207 (5.0) | 127 (6.0) |
| Former | 18,093 (3.6) | 298 (5.1) | 17,795 (3.6) | 199 (4.8) | 119 (5.6) |
| Current, <3 drink/month | 113,825 (22.7) | 1,465 (25.3) | 112,360 (22.6) | 1001 (24.0) | 586 (27.7) |
| Current, <1 drink/day | 124,784 (24.8) | 1,383 (23.9) | 123,401 (24.9) | 998 (23.9) | 499 (23.6) |
| Current, 1 to 3 drink/day | 179,516 (35.7) | 1,920 (33.1) | 177,594 (35.8) | 1,426 (34.2) | 642 (30.4) |
| Current, >3 drink/day | 41,971 (8.4) | 420 (7.2) | 41,551 (8.4) | 327 (7.8) | 133 (6.3) |
| Physical activity, days/week, n (%) | |||||
| 0 | 52,690 (10.5) | 701 (12.1) | 51,989 (10.5) | 498 (11.9) | 266 (12.6) |
| 1–2 | 63,530 (12.7) | 756 (13.0) | 62,774 (12.6) | 506 (12.1) | 314 (14.9) |
| 3–4 | 81,860 (16.3) | 934 (16.1) | 80,926 (16.3) | 681 (16.3) | 326 (15.4) |
| >=5 | 261,669 (52.1) | 2,852 (49.2) | 258,817 (52.1) | 2,100 (50.3) | 996 (47.1) |
| Aspirin use, n (%) | 69,642 (13.9) | 818 (14.1) | 68,824 (13.9) | 620 (14.9) | 272 (12.9) |
| Ibuprofen use, n (%) | 73,279 (14.6) | 655 (11.3) | 72,624 (14.6) | 454 (10.9) | 246 (11.6) |
| Laxative use, n (%) | 14,888 (3.0) | 189 (3.3) | 14,699 (3.0) | 134 (3.2) | 69 (3.3) |
| Diabetes, n (%) | 21,719 (4.3) | 307 (5.3) | 21,412 (4.3) | 226 (5.4) | 109 (5.2) |
| Hypertension, n (%) | 130,956 (26.1) | 1,581 (27.3) | 129,375 (26.1) | 1,129 (27.1) | 594 (28.1) |
| Asthma, n (%) | 58,258 (11.6) | 802 (13.8) | 57,456 (11.6) | 561 (13.4) | 309 (14.6) |
| Tuberculosis, n (%) | 2,542 (0.5) | 42 (0.7) | 2,500 (0.5) | 28 (0.7) | 18 (0.9) |
NOTE: inflammatory bowel diseases (IBD); ulcerative colitis (CD); Crohn’s disease (CD); body mass index (BMI).
a
Numbers may not sum to n=502,369, and percentages may not sum to 100% owing to missing data.
b
Physical activity measured by number of days/week of >10 min of moderate or vigorous activity.