Baseline | Time of first exposure | ||||
Unexposed (n=657 284) | Exposed (n=263 037) | Standardised difference versus unexposed* | Exposed (n=263 037) | Standardised difference vs. unexposed* | |
Demographics | |||||
Age category, N (%) | |||||
Prepubertal (2–9 years) | 102 588 (15.6) | 37 961 (14.4) | −0.02 | 28 638 (10.9) | −0.14 |
Older child/adolescent (10–17 years) | 76 710 (11.7) | 16 364 (6.2) | −0.20 | 18 000 (6.8) | −0.17 |
Younger adult (18–49 years) | 333 829 (50.8) | 108 376 (41.2) | −0.19 | 101 988 (38.8) | −0.24 |
Older adult (≥50 years) | 144 157 (21.9) | 100 336 (38.2) | 0.34 | 114 411 (43.5) | 0.47 |
Male sex, N (% cohort by age) | 320 021 (48.7) | 112 426 (42.7) | −0.12 | 112 426 (42.7) | −0.12 |
Prepubertal (2–9 years) | 57 822 (56.4) | 23 598 (60.2) | 0.08 | 17 803 (62.2) | 0.12 |
Older child/adolescent (10–17 years) | 41 991 (54.7) | 7788 (48.6) | −0.12 | 9994 (55.5) | 0.02 |
Younger adult (18–49 years) | 157 187 (47.1) | 41 173 (37.6) | −0.19 | 38 406 (37.7) | −0.19 |
Older adult (≥50) | 63 021 (43.7) | 39 867 (40.5) | −0.07 | 46 223 (40.4) | −0.07 |
Country, N (%) | † | ||||
England | 524 879 (79.9) | 212 211 (80.7) | 0.02 | ||
Northern Ireland | 18 183 (2.8) | 7507 (2.9) | 0.005 | ||
Scotland | 71 170 (10.8) | 26 117 (9.9) | −0.03 | ||
Wales | 43 052 (6.5) | 17 202 (6.5) | 0.000 | ||
Townsend score‡, N (%) | † | ||||
1 | 104 947 (16.0) | 48 254 (18.3) | 0.06 | ||
2 | 90 966 (13.8) | 43 494 (16.5) | 0.08 | ||
3 | 91 257 (13.9) | 43 866 (16.7) | 0.08 | ||
4 | 86 797 (13.2) | 41 181 (15.7) | 0.07 | ||
5 | 62 305 (9.5) | 30 221 (11.5) | 0.07 | ||
Missing | 221 012 (33.6) | 56 021 (21.3) | −0.28 | ||
Year of cohort entry, N (%) | |||||
1994–1998 | 114 863 (17.0) | 72 716 (23.3) | 0.17 | 22 989 (7.4) | −0.36 |
1999–2003 | 268 260 (39.6) | 141 382 (45.3) | 0.13 | 90 697 (29.1) | −0.26 |
2004–2008 | 182 761 (27.0) | 74 167 (23.8) | −0.09 | 112 291 (36.0) | 0.22 |
2009–2013 | 110 925 (16.4) | 23 932 (7.7) | −0.30 | 86 220 (27.6) | 0.32 |
Follow-up time, median (IQR) | 5.7 (2.4, 10.7) | 9.6 (5.5, 12.6) | 4.4 (2.0, 7.9) | ||
Inclusion diagnoses, N (%) | † | ||||
Inflammatory disease§ | |||||
Asthma | 525 446 (79.9) | 231 272 (87.9) | 0.22 | ||
Psoriasis | 94 300 (14.3) | 19 354 (7.4) | −0.23 | ||
Arthritis | 40 818 (6.2) | 17 646 (6.7) | 0.02 | ||
Inflammatory bowel disease | 27 206 (4.1) | 15 783 (6.0) | 0.09 | ||
Systemic lupus erythematosus | 3350 (0.5) | 1761 (0.7) | 0.02 | ||
Two or more inclusion diagnoses | 32 640 (5.0) | 21 439 (8.2) | 0.13 | ||
Medical comorbidities, N (%) | |||||
Cardiovascular disease | 22 427 (3.4) | 15 178 (5.8) | 0.11 | 20 645 (7.8) | 0.19 |
Chronic kidney disease | 3825 (0.6) | 1503 (0.6) | −0.003 | 7055 (2.7) | 0.16 |
End-stage renal disease | 633 (0.1) | 272 (0.1) | 0.002 | 771 (0.3) | 0.04 |
Diabetes mellitus | 18 466 (2.8) | 8907 (3.4) | 0.03 | 15 770 (6.0) | 0.16 |
Hypertension | 51 073 (7.8) | 32 171 (12.2) | 0.15 | 46 226 (17.6) | 0.30 |
Other rheumatic disease, any | 9308 (1.4) | 5703 (2.2) | 0.06 | 9846 (3.7) | 0.15 |
Connective tissue disease¶ | 1448 (0.2) | 1034 (0.4) | 0.03 | 1535 (0.6) | 0.06 |
Gout | 6229 (1.0) | 3899 (1.5) | 0.05 | 6884 (2.6) | 0.13 |
Vasculitis | 1728 (0.3) | 856 (0.3) | 0.01 | 1628 (0.6) | 0.05 |
Stroke | 8852 (1.4) | 5057 (1.9) | 0.05 | 7731 (2.9) | 0.11 |
Thrombosis or thrombophilia** | 10 212 (1.6) | 6930 (2.6) | 0.08 | 10 779 (4.1) | 0.15 |
Musculoskeletal comorbidities, N (%) | |||||
Dislocation | 7327 (1.1) | 2899 (1.1) | −0.001 | 3659 (1.4) | 0.03 |
Fracture | 110 625 (16.8) | 41 854 (15.9) | −0.03 | 51 384 (19.5) | 0.07 |
Osteoarthritis | 38 721 (5.9) | 27 516 (10.5) | 0.17 | 39 817 (15.1) | 0.31 |
Osteoporosis | 5210 (0.8) | 3452 (1.3) | 0.05 | 6191 (2.4) | 0.13 |
Slipped capital femoral epiphysis | 209 (0.03) | 70 (0.03) | −0.003 | 79 (0.03) | −0.001 |
Medications, N (%) | |||||
Non-oral glucocorticoids, any | 418 983 (63.7) | 177 752 (67.6) | 0.08 | 234 529 (89.2) | 0.63 |
Inhaled | 261 282 (39.8) | 118 575 (45.1) | 0.11 | 180 098 (68.5) | 0.60 |
Intravenous | 530 (0.1) | 503 (0.2) | 0.03 | 851 (0.3) | 0.05 |
Local injections | 14 671 (2.2) | 11 172 (4.3) | 0.11 | 20 958 (8.0) | 0.26 |
Intranasal | 86 168 (13.1) | 40 489 (15.4) | 0.07 | 68 316 (26.0) | 0.33 |
Rectal | 20 847 (3.2) | 11 991 (4.6) | 0.07 | 22 202 (8.4) | 0.23 |
Topical | 230 490 (35.1) | 97 029 (36.9) | 0.04 | 140 960 (53.6) | 0.38 |
Prior oral glucocorticoids | 64 718 (9.9) | 52 032 (19.8) | 0.28 | 52 032 (19.8) | 0.28 |
Anticoagulant | 6046 (0.9) | 3901 (1.5) | 0.05 | 6996 (2.7) | 0.13 |
Bisphosphonate | 4981 (0.8) | 3310 (1.3) | 0.05 | 7956 (3.0) | 0.17 |
Calcium | 2760 (0.4) | 1927 (0.7) | 0.04 | 3239 (1.2) | 0.09 |
Hormones†† | 116 214 (17.7) | 52 860 (20.1) | 0.06 | 68 345 (26.0) | 0.20 |
Immunosuppressant | 25 464 (3.9) | 12 277 (4.7) | 0.04 | 22 770 (8.7) | 0.20 |
Statin | 25 811 (3.9) | 14 187 (5.4) | 0.07 | 32 949 (12.5) | 0.32 |
Vitamin D | 10 243 (1.6) | 4815 (1.8) | 0.02 | 13 270 (5.0) | 0.20 |
Lifestyle factors, N (%) | |||||
Alcohol use | |||||
None/light | 345 348 (52.5) | 169 129 (64.3) | 0.24 | 169 129 (64.3) | 0.24 |
Heavy/problematic | 28 605 (4.4) | 11 445 (4.4) | 0.000 | 15 032 (5.7) | 0.06 |
Missing | 283 331 (43.1) | 82 463 (31.4) | −0.25 | 78 876 (30.0) | −0.28 |
Tobacco use | |||||
Never | 242 904 (37.0) | 100 142 (38.1) | 0.02 | 100,142 (38.1) | 0.02 |
Ever | 200 303 (30.5) | 93 585 (35.6) | 0.11 | 120,986 (46.0) | 0.32 |
Missing | 214 077 (32.6) | 69 310 (26.4) | −0.14 | 41,909 (15.9) | -0.40 |
Health utilisation | |||||
Hospitalisation, N (%) | 53 765 (8.2) | 25 610 (9.7) | 0.06 | 48 626 (18.5) | 0.31 |
Number of distinct medication classes in prior 6 months, median (IQR) | 2 (1,4) | 3 (1,5) | 0.29 | 4 (2, 6) | 0.66 |
Number of outpatient encounters in prior 6 months, median (IQR) | 2 (0, 4) | 2 (1, 4) | 0.08 | 5 (2, 9) | 0.39 |
Specialist referral‡‡, N (%) | 50 793 (7.7) | 20 378 (7.8) | 0.001 | 51 085 (19.4) | 0.35 |
*Standardised differences >0.1 or <−0.1 suggest imbalance.
†Not updated at time of exposure; same as baseline values.
‡Local measures of deprivation, ranging from 1 (lowest local deprivation) to 5 (highest local deprivation).
§Some patients had more than one diagnosis.
¶Connective tissue diseases other than systemic lupus, including Sjögren syndrome, systemic sclerosis, mixed connective tissue disease, dermato/polymyositis.
**Not including stroke.
††Hormonal contraceptives or hormone replacement therapy.
‡‡Including only specialists who manage chronic inflammatory diseases of interest.