Participants characteristics at baseline assessment. Figures are numbers and percentages unless otherwise specified
| RA, n=5764 | Psoriasis, n=6286 | AS, n=1400 | Vasculitis, n=1475 | SLE, n=654 | UC, n=2659 | CD, n=1494 | Unexposed, n=483 559 | |
| Age—mean (SD) | 46 (14) | 33 (17) | 37 (13) | 57 (11) | 42 (12) | 39 (13) | 36 (14) | 57 (8) |
| Gender —Female | 4014 (70) | 2991 (48) | 528 (38) | 986 (67) | 582 (89) | 1427 (54) | 861 (58) | 261 549 (54) |
| Ethnicity | ||||||||
| White | 5431 (94) | 6070 (96) | 1352 (97) | 1435 (98) | 561 (86) | 2542 (96) | 1451 (98) | 453 485 (94) |
| Mixed | 135 (2) | 98 (2) | 13 (1) | 9 (1) | 23 (4) | 57 (2) | 21 (1) | 9512 (2) |
| Asian | 73 (1) | 16 (0) | 4 (0) | 8 (0) | 42 (6) | 16 (1) | 9 (1) | 7887 (2) |
| Black | 38(1) | 31(1) | 8 (1) | 6 (0) | 10 (2) | 13 (0) | 3 (0) | 2850 (1) |
| Other | 54 (1) | 41 (1) | 13 (1) | 10 (1) | 13 (2) | 23(1) | 4 (0) | 6019 (1) |
| Deprivation quintile | ||||||||
| Least deprived | 1015 (18) | 1181 (19) | 268 (19) | 321 (22) | 115 (18) | 539 (20) | 274 (18) | 96 898 (20) |
| Second | 1011 (18) | 1185 (19) | 277 (20) | 287 (20) | 110 (17) | 552 (21) | 289 (18) | 96 292 (20) |
| Third | 1107 (19) | 1229 (19) | 262 (19) | 333 (23) | 120 (18) | 550 (21) | 286 (19) | 96 418 (20) |
| Fourth | 1176 (20) | 1266 (20) | 283 (20) | 296 (20) | 128 (20) | 551 (21) | 314 (21) | 96 240 (20) |
| Most deprived | 1445 (25) | 1420 (23) | 309 (22) | 235 (16) | 180 (28) | 464 (17) | 327 (22) | 95 935 (20) |
| Qualifications | ||||||||
| Degree level | 434 (8) | 614 (10) | 139 (10) | 126 (9) | 58 (9) | 248 (9) | 134 (9) | 53 777 (11) |
AS, ankylosing spondylitis; CD, Crohn’s disease; RA, rheumatoid arthritis; SLE, systemic lupus erythematosus; UC, ulcerative colitis.