Table 2

Baseline characteristics of ever and never TNFi exposed patients in the two cohorts divided by arthritic disease

Demographics characteristicsRheumatoid arthritisAnkylosing spondylitis and psoriatic arthritis
SwedenDenmarkSwedenDenmark
TNFi exposedTNFi unexposedTNFi exposedTNFi unexposedTNFi exposedTNFi unexposedTNFi exposedTNFi unexposed
Total, n18 59878 719719826 00613 61548 28844989611
Women, n (%)14 011 (75)56 036 (71)5350 (74)18 372 (71)6286 (46)23 665 (49)1872 (42)4747 (49)
Age at entry (years), median (IQR)57
(47–66)
65
(54–74)
57
(48–65)
63
(52–72)
45
(35–55)
51
(39–61)
45
(35–54)
49
(39–60)
Median years of follow-up, median (IQR)7.4
(3.7–12)
6.1
(2.7–11)
7.4
(4.2–10)
3.6
(1.8–6.1)
5.3
(2.6–9.1)
6.8
(3.1–12)
6.6
(3.7–9.4)
2.7
(1.1–4.9)
Age at rheumatological diagnosis, years, median (IQR)
(missing)
46
(35–56)
(325)
61
(50–71)
(0)
48
(37–57)
(490)
55
(44–66)
(3,743)
31
(23–42)
(130)
47
(36–58)
(0)
37
(28–47)
(622)
43
(33–54)
(2,670)
Calendar year of inclusion, n (%)
 2000–20055350 (29)39 954 (51)1806 (25)627 (2)1636 (12)17 951 (37)611 (14)106 (1)
 2006–20116760 (36)21 917 (28)3376 (47)11 014 (42)4773 (35)16 253 (34)2185 (49)2899 (30)
 2012–20176488 (35)16 848 (21)2016 (28)14 365 (55)7206 (53)14 084 (29)1702 (38)6606 (69)
Smoking status, n (%)
 Current801 (4)1680 (23)4801 (18)735 (5)1301 (29)1770 (18)
 Previous2157 (12)1869 (26)5852 (23)1837 (13)895 (20)1696 (18)
 Never2065 (11)2690 (37)9314 (36)2502 (18)1860 (41)3638 (38)
 Missing13 575 (73)78 719 (100)959 (13)6038 (23)8541 (63)48 288 (100)442 (10)2507 (26)
Disease related characteristics
 Disease duration, years, median (IQR) (missing)6.9 (2.5–15)
(321)
0.5 (0.2–3.0)
(0)
6.0 (2.2–14)
(490)
1.4 (0.1–8.9)
(3743)
8.6 (3.3–17)
(126)
0.5 (0.2–2.1)
(0)
3.4 (0.9–9.9)
(622)
1.1 (0.1–6.5)
(2 670)
 Disease duration <2 years, n
 (%)
 (missing)
3693 (20)
(321)
56 120 (71)
(0)
1542 (23)
(490)
11 856 (53)
(3 743)
2211(16)
(126)
35 929
(74)
(0)
1544
(44)
(622)
3970
(57)
(2 670)
 Tender joint count (0–28 scale), median (IQR) (missing)6
(3-11)
(3188)
(78 719)8
(8-13)
(1182)
3
(0–7)
(1701)
2
(0–6)
(4269)
(48 288)6
(2-11)
(699)*
2
(0–6)
(893)*
 Swollen joint count (0–28 scale), median (IQR) (missing)6
(3-11)
(3167)
(78 719)5
(2-9)
(1179)
2
(0–5)
(1643)
1
(0–4)
(4257)
(48 288)2
(0–5)
(709)*
0
(0–2)
(930)*
 DAS28-CRP, median (IQR) (missing)4.8
(3.9–5.6)
(4296)
(78 719)4.8
(3.7–5.6)
(1513)
3.4
(2.1–4.6)
(5627)
3.6
(2.7–4.6)
(5429)
(48 288)4.3
(3.2–5.2)
(861)*
3.1
(1.9–4.2)
(2152)*
 BASDAI (0–10 scale), median (IQR) (missing)(13 615)(48 288)60
(46-73)
(1788)
46
(26-64)
(2867)
 CRP, mg/L, median (IQR) (missing)11
(5–28)
(3214)
(78 719)12
(5–27)
(1100)
7
(3–16)
(2373)
7
(3–18)
(3538)
(48 288)9
(3–20)
(1098)
5
(2–11)
(1918)
 HAQ (0–3 scale), median (IQR) (missing)1.1
(0.6–1.6)
(4076)
(78 719)1.3
(0.8–1.8)
(1304)
0.8
(0.3–1.3)
(3901)
 Seropositive RA, n (%) (missing)2437
(39)
(12 348)
(78 719)5412
(75)
(463)
16 882
(72)
(2452)
Concomitant medication, n (%)
 Methotrexate11 533 (62)4832 (67)15 041 (58)4607 (34)1726 (38)3591 (37)
 Oral steroid8226 (44)1911 (27)3130 (12)2131 (16)225 (5)235 (2)
TNFi, n (%)
 Adalimumab (Humira)3264 (18)1776 (25)3620 (27)1600 (36)
 Infliximab (Remicade,
Remsima, Inflectra)
6353 (34)2555 (36)3947 (29)1308 (29)
 Etanercept (Enbrel, Benepali)6959 (37)1773 (25)4389 (32)876 (20)
 Golimumab (Simponi)906 (5)199 (3)1168 (9)430 (10)
 Certolozumab pegol (Cimzia)1116 (6)895 (12)491 (4)284 (6)
  • Data are expressed as numbers (%) or median values (IQR).

  • *Only among psoriatic arthritis patients.

  • BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; CRP, C reactive protein; DAS28, Disease Activity Score using 28 joint count; HAQ, Health Assessment Questionnaire; RA, rheumatoid arthritis; TNFi, tumour necrosis factor-α inhibitor.