Table.
Baseline demographics and comorbidities for people with incident inflammatory arthritis diagnoses, overall and separated into subdiagnoses, compared with the reference population
| General population (n=17 683 500) | All inflammatory arthritis (n=31 280) | Rheumatoid arthritis (n=19 085) | Psoriatic arthritis (n=6825) | Axial spondyloarthritis (n=3970) | Undifferentiated inflammatory arthritis (n=1400) | ||
|---|---|---|---|---|---|---|---|
| Age group, years | |||||||
| 18–39 | 6 049 070 (34·2%) | 6225 (19·9%) | 2080 (10·9%) | 1995 (29·2%) | 1865 (47·0%) | 285 (20·4%) | |
| 40–49 | 2 930 905 (16·6%) | 5030 (16·1%) | 2375 (12·4%) | 1555 (22·8%) | 860 (21·7%) | 240 (17·1%) | |
| 50–59 | 3 124 025 (17·7%) | 6935 (22·2%) | 4255 (22·3%) | 1740 (25·5%) | 650 (16·4%) | 290 (20·7%) | |
| 60–69 | 2 455 845 (13·9%) | 5820 (18·6%) | 4310 (22·6%) | 935 (13·7%) | 310 (7·8%) | 260 (18·6%) | |
| 70–79 | 1 971 630 (11·1%) | 5130 (16·4%) | 4240 (22·2%) | 505 (7·4%) | 175 (4·4%) | 205 (14·6%) | |
| ≥80 | 1 152 025 (6·5%) | 2140 (6·8%) | 1825 (9·6%) | 95 (1·4%) | 105 (2·6%) | 120 (8·6%) | |
| Sex | |||||||
| Female | 8 866 535 (50·1%) | 18 615 (59·5%) | 12 385 (64·9%) | 3675 (53·8%) | 1750 (44·1%) | 805 (57·5%) | |
| Male | 8 816 965 (49·9%) | 12 665 (40·5%) | 6700 (35·1%) | 3150 (46·2%) | 2220 (55·9%) | 595 (42·5%) | |
| Ethnicity | |||||||
| White | 12 025 695 (86·6%) | 22 925 (88·3%) | 13 825 (87·2%) | 5175 (90·9%) | 2900 (88·5%) | 1025 (89·5%) | |
| Asian or Asian British | 1 029 955 (7·4%) | 1965 (7·6%) | 1320 (8·3%) | 360 (6·3%) | 220 (6·7%) | 65 (5·7%) | |
| Black | 343 885 (2·5%) | 465 (1·8%) | 350 (2·2%) | 35 (0·6%) | 55 (1·7%) | 25 (2·2%) | |
| Mixed or other | 493 170 (3·5%) | 605 (2·3%) | 355 (2·2%) | 120 (2·1%) | 100 (3·1%) | 30 (2·6%) | |
| Missing | 3 790 795 | 5315 | 3235 | 1130 | 695 | 255 | |
| Index of multiple deprivation | |||||||
| 1 (most deprived) | 3 285 410 (18·9%) | 5660 (18·5%) | 3570 (19·1%) | 1235 (18·5%) | 670 (17·3%) | 185 (13·5%) | |
| 2 | 3 557 860 (20·4%) | 5960 (19·5%) | 3745 (20·0%) | 1250 (18·8%) | 735 (18·9%) | 230 (16·8%) | |
| 3 | 3 762 515 (21·6%) | 6945 (22·7%) | 4270 (22·8%) | 1490 (22·4%) | 870 (22·4%) | 315 (23·0%) | |
| 4 | 3 448 770 (19·8%) | 6385 (20·8%) | 3845 (20·5%) | 1385 (20·8%) | 815 (21·0%) | 340 (24·8%) | |
| 5 (least deprived) | 3 360 490 (19·3%) | 5675 (18·5%) | 3285 (17·6%) | 1300 (19·5%) | 790 (20·4%) | 300 (21·9%) | |
| Missing | 268 455 | 650 | 370 | 165 | 90 | 25 | |
| BMI, kg/m2 | |||||||
| Underweight (<18·5) | 319 635 (2·3%) | 430 (1·6%) | 295 (1·7%) | 60 (1·0%) | 65 (2·0%) | 10 (0·8%) | |
| Healthy weight (18·5–24·9) | 4 850 520 (35·1%) | 7850 (28·6%) | 4880 (28·5%) | 1400 (23·9%) | 1180 (36·8%) | 390 (31·5%) | |
| Overweight (25–29·9) | 4 779 205 (34·6%) | 9530 (34·7%) | 6140 (35·8%) | 1890 (32·2%) | 1055 (32·9%) | 445 (35·9%) | |
| Obese I (30–34·9) | 2 416 505 (17·5%) | 5700 (20·8%) | 3565 (20·8%) | 1330 (22·7%) | 535 (16·7%) | 265 (21·4%) | |
| Obese II (35–39·9) | 926 190 (6·7%) | 2430 (8·8%) | 1405 (8·2%) | 700 (11·9%) | 240 (7·5%) | 85 (6·9%) | |
| Obese III (≥40) | 529 075 (3·8%) | 1520 (5·5%) | 850 (5·0%) | 490 (8·3%) | 135 (4·2%) | 45 (3·6%) | |
| Missing | 3 862 370 | 3815 | 1950 | 950 | 760 | 160 | |
| Smoking status | |||||||
| Never | 8 132 435 (47·9%) | 11 725 (37·9%) | 6905 (36·5%) | 2590 (38·4%) | 1640 (42·5%) | 590 (42·9%) | |
| Former | 5 831 370 (34·3%) | 13 330 (43·1%) | 8530 (45·0%) | 2920 (43·3%) | 1305 (33·9%) | 575 (41·8%) | |
| Current | 3 024 645 (17·8%) | 5 860 (19·0%) | 3500 (18·5%) | 1235 (18·3%) | 910 (23·6%) | 210 (15·3%) | |
| Missing | 695 050 | 360 | 150 | 75 | 110 | 20 | |
| Comorbidities | |||||||
| Hypertension | 3 771 745 (21·3%) | 9005 (28·8%) | 6580 (34·5%) | 1430 (21·0%) | 570 (14·4%) | 420 (30·0%) | |
| Diabetes | |||||||
| No diabetes | 15 973 490 (90·3%) | 26 460 (84·6%) | 15 605 (81·8%) | 5995 (87·8%) | 3660 (92·2%) | 1195 (85·4%) | |
| Diabetes with HbA1c <58 mmol/mol | 1 084 530 (6·1%) | 3270 (10·5%) | 2420 (12·7%) | 525 (7·7%) | 195 (4·9%) | 130 (9·3%) | |
| Diabetes with HbA1c >58 mmol/mol | 498 030 (2·8%) | 1300 (4·2%) | 900 (4·7%) | 255 (3·7%) | 85 (2·1%) | 65 (4·6%) | |
| Diabetes with no HbA1c measure | 127 450 (0·7%) | 250 (0·8%) | 160 (0·8%) | 50 (0·7%) | 30 (0·8%) | 10 (0·7%) | |
| Chronic cardiac disease | 1 192 945 (6·7%) | 2975 (9·5%) | 2285 (12·0%) | 350 (5·1%) | 195 (4·9%) | 145 (10·4%) | |
| Stroke | 370 030 (2·1%) | 815 (2·6%) | 630 (3·3%) | 85 (1·2%) | 60 (1·5%) | 40 (2·9%) | |
| Cancer | 953 380 (5·4%) | 2045 (6·5%) | 1485 (7·8%) | 280 (4·1%) | 145 (3·7%) | 135 (9·6%) | |
| Chronic respiratory disease | 715 820 (4·0%) | 2580 (8·2%) | 2080 (10·9%) | 285 (4·2%) | 130 (3·3%) | 80 (5·7%) | |
| Chronic liver disease | 98 535 (0·6%) | 280 (0·9%) | 160 (0·8%) | 85 (1·2%) | 25 (0·6%) | 10 (0·7%) | |
| Chronic kidney disease | 1 123 905 (6·4%) | 2270 (7·3%) | 1810 (9·5%) | 245 (3·6%) | 110 (2·8%) | 105 (7·5%) | |
Counts have been rounded to the nearest 5, to reduce the risk of disclosure; as such, column totals might differ from the sum of the individual variables. HbA1c=glycated haemoglobin.