TABLE 1.
Baseline characteristics of study population
| IBD status | Crohn’s disease | Ulcerative colitis | Controls | P value |
|---|---|---|---|---|
| 4,436 | 10,089 | 58,027 | ||
| Demographics | ||||
| Men: n (%) | 2096 (47) | 5396 (53) | 29 930 (52) | 0.99 |
| Age at diagnosis: n (%) | ||||
| <18 years | 492 (12) | 372 (4) | 3452 (6) | 0.99 |
| 18‐25 years | 504 (12) | 553 (6) | 4226 (8) | 0.98 |
| 25‐40 years | 1092 (26) | 2377 (24) | 13 866 (25) | 0.97 |
| 40‐60 years | 1216 (29) | 3267 (34) | 17 910 (32) | 0.99 |
| ≥60 years | 958 (22) | 3204 (33) | 16 617 (30) | 0.96 |
| Social deprivation: n (%) | ||||
| IMD* 1‐3 | 1614 (37) | 4131 (41) | 21 337 (37) | <0.0001 |
| IMD 4‐5 | 918 (21) | 1780 (18) | 12 151 (21) | <0.0001 |
| Unknown | 1904 (42) | 4178 (41) | 24 539 (42) | <0.0001 |
| Smoking status n (%) | ||||
| Smoker | 1110 (25) | 1044 (10) | 5506 (9) | <0.0001 |
| Ex‐smoker | 1037 (23) | 3752 (37) | 6591 (11) | <0.0001 |
| Never | 1198 (27) | 2895 (29) | 22 458 (38) | <0.0001 |
| Missing | 1091 (25 | 2398 (24) | 23 472 (40) | <0.0001 |
*
IMD, Index of Multiple Deprivation; IMD 1 represents the least deprived and IMD 5 the most deprived. Data are available only for individual’s resident in England.