Covariate summary statistics for ulcerative colitis, Crohn’s disease and control cohorts
| With CD (n=7469) | Matched cohort without CD (n=29 876) | With UC (n=11 360) | Matched cohort without UC (n=45 440) | |
| Age at study entry (years) Median (IQR) | 47 (34, 61) | 48 (33, 63) | 53 (39, 67) | 52 (37, 67) |
| Male sex | 3402 (45.5) | 14 085 (47.1) | 5737 (50.5) | 22 433 (49.4) |
| Time since GP practice registration (years) median (IQR) | 10 (2, 20) | 11 (3, 20) | 11 (3, 21) | 11 (3, 21) |
| Duration of IBD (years) median (IQR) | 9 (2, 17) | NA | 9 (2, 18) | NA |
| Ethnicity | ||||
| Asian | 247 (4.2) | 1402 (6.0) | 547 (6.1) | 2239 (6.3) |
| Black | 72 (1.2) | 599 (2.6) | 93 (1.0) | 811 (2.3) |
| Mixed | 55 (0.9) | 246 (1.1) | 63 (0.7) | 361 (1.0) |
| Other | 41 (0.7) | 235 (1.0) | 68 (0.8) | 299 (0.8) |
| White | 5399 (92.9) | 20 732 (89.3) | 8270 (91.5) | 32 058 (89.6) |
| BMI category (kg/m2) | ||||
| Underweight (≤18.5) | 369 (4.9) | 800 (2.7) | 256 (2.3) | 1094 (2.4) |
| Normal weight (18.5–25) | 3020 (40.4) | 10 170 (34.0) | 4230 (37.2) | 14 905 (32.8) |
| Overweight (25-30) | 2125 (28.5) | 8819 (29.5) | 3684 (32.4) | 14 399 (31.7) |
| Obese (≥30) | 1304 (17.5) | 6307 (21.1) | 2223 (19.6) | 9744 (21.4) |
| BMI not recorded | 651 (8.7) | 3780 (12.7) | 967 (8.5) | 5298 (11.7) |
| Smoking status | ||||
| Non-smoker | 2641 (35.4) | 12 511 (41.9) | 4255 (37.5) | 18 288 (40.2) |
| Current smoker | 1731 (23.2) | 6135 (20.5) | 1386 (12.2) | 8881 (19.5) |
| Ex-smoker | 3028 (40.5) | 10 632 (35.6) | 5631 (49.6) | 17 594 (38.7) |
| Smoking status not recorded | 69 (0.9) | 598 (2.0) | 88 (0.8) | 677 (1.5) |
| Index of multiple deprivation quintile | ||||
| 1 (most deprived) | 1015 (13.6) | 4130 (13.8) | 1293 (11.4) | 5534 (12.2) |
| 2 | 1185 (15.9) | 4738 (15.9) | 1626 (14.3) | 6694 (14.7) |
| 3 | 1484 (19.9) | 5867 (19.6) | 2143 (18.9) | 8779 (19.3) |
| 4 | 1765 (23.6) | 6840 (22.9) | 2862 (25.2) | 11 024 (24.3) |
| 5 (least deprived) | 1860 (24.9) | 7704 (25.8) | 3230 (28.4) | 12 579 (27.7) |
| IMD not recorded | 160 (2.1) | 597 (2.0) | 206 (1.8) | 830 (1.8) |
| Alcohol intake | ||||
| Non-drinker | 1158 (15.5) | 3945 (13.2) | 1495 (13.2) | 5799 (12.8) |
| Within limits | 4178 (55.9) | 16 449 (55.1) | 6724 (59.2) | 25 880 (57.0) |
| Over recommended limits | 991 (13.3) | 4390 (14.7) | 1691 (14.9) | 6882 (15.1) |
| Alcoholism | 119 (1.6) | 505 (1.7) | 172 (1.5) | 774 (1.7) |
| Alcohol intake not recorded | 1023 (13.7) | 4587 (15.4) | 1278 (11.2) | 6105 (13.4) |
| Comorbidities | ||||
| Hypertension | 1292 (17.3) | 5894 (19.7) | 2704 (23.8) | 10 929 (24.1) |
| Hyperlipidaemia | 1391 (18.6) | 7462 (25.0) | 3293 (29.0) | 13 480 (29.7) |
| Type two diabetes | 436 (5.8) | 1992 (6.7) | 1052 (9.3) | 3674 (8.1) |
| Peripheral vascular disease | 81 (1.1) | 276 (0.9) | 139 (1.2) | 584 (1.3) |
| Atrial fibrillation | 172 (2.3) | 797 (2.7) | 388 (3.4) | 1479 (3.3) |
| Myocardial infarction | 172 (2.3) | 694 (2.3) | 424 (3.7) | 1360 (3.0) |
| Angina | 139 (1.9) | 531 (1.8) | 337 (3.0) | 1101 (2.4) |
| Stroke | 119 (1.6) | 430 (1.4) | 226 (2.0) | 831 (1.8) |
| Heart failure | 87 (1.2) | 322 (1.1) | 179 (1.6) | 675 (1.5) |
| CKD stages 3–5 | 406 (5.4) | 1344 (4.5) | 796 (7.0) | 2897 (6.4) |
| COPD | 111 (1.5) | 179 (0.6) | 235 (2.1) | 285 (0.6) |
| Chronic liver disease | 364 (4.9) | 922 (3.1) | 489 (4.3) | 1696 (3.7) |
| Malignancy | 315 (4.2) | 1308 (4.4) | 689 (6.1) | 2479 (5.5) |
| Dementia | 136 (1.8) | 611 (2.0) | 292 (2.6) | 1230 (2.7) |
| Rheumatoid arthritis | 85 (1.1) | 194 (0.6) | 157 (1.4) | 383 (0.8) |
| History of fracture | 612 (8.2) | 2371 (7.9) | 1017 (9.0) | 3721 (8.2) |
| Depression | 1160 (15.5) | 3091 (10.3) | 1461 (12.9) | 4786 (10.5) |
| Baseline medication use | ||||
| Rectal 5-ASA | 329 (4.4) | 25 (0.1) | 2415 (21.3) | 35 (0.1) |
| Rectal glucocorticoids | 340 (4.6) | 263 (0.9) | 1793 (15.8) | 395 (0.9) |
| Oral 5-ASA | 2868 (38.4) | 97 (0.3) | 6986 (61.5) | 212 (0.5) |
| Oral glucocorticoids | 2290 (30.7) | 1780 (6.0) | 2937 (25.9) | 3103 (6.8) |
| Non-biologic immunosuppressants | 2274 (30.4) | 207 (0.7) | 1600 (14.1) | 377 (0.8) |
| Biologic therapies | 182 (2.4) | 6 (0.0) | 59 (0.5) | 7 (0.0) |
Data are N (%) unless stated.
5-ASA, aminosalicylic acid medications; BMI, body mass index; CD, Crohn’s disease; CKD, chronic kidney disease; COPD, chronic obstructive pulmonary disease; GP, general practitioner; IBD, inflammatory bowel disease; UC, ulcerative colitis.