Table 1 Baseline characteristics of treatment courses for axSpA patients initiating a TNFi

Age (years), median (IQR)

42 (33–51)

43 (34–51)

41 (32-51)

Men, n (%)

886 (53.1)

531 (47.5)

355 (64.4)

BMI, median (IQR)

25.3 (22.5–28.6)

n=1408

25.7 (22.8–29.3)

n=932

24.7 (22.3-27.3)

n=476

Disease duration (years), median (IQR)

9 (4–18)

n=1633

9 (4–17)

n=1092

10 (4-19)

n=541

HLA-B27+, n (%)

984 (65.7)

n=1498

617 (61.5)

n=1003

367 (74.1)

n=495

ASAS axial SpA criteria positive, n (%)^a

1158 (76.4)

n=1515

764 (76.2)

n=1003

396 (77.2)

n=513

Enthesitis (mMASES >0) at baseline, n (%)

1117 (67.0)

1117 (100)

-

mMASES, median (IQR)

2 (0–4)

3 (2–6)

-

Elevated CRP, n (%)

987 (60.1)

n=1642

641 (58.4)

n=1098

346 (63.6)

n=544

ASDAS-CRP^b, median (IQR)

3.3 (2.6–3.9)

n=1220

3.4 (2.8–4.0)

n=816

3.0 (2.3-3.7)

n=404

BASDAI score^c, median (IQR)

5.7 (4.1–7.0)

n=1337

6.1 (4.7–7.3)

n=889

4.6 (2.9-6.2)

n=448

Ever experienced uveitis, n (%)

258 (16.5)

n=1567

146 (13.9)

n=1054

112 (21.8)

n=513

Ever experienced arthritis, n (%)

963 (57.7)

707 (63.3)

256 (46.5)

Ever experienced dactylitis, n (%)

214 (12.9)

n=1655

168 (15.0)

n=1108

46 (10.3)

n=447

Ever experienced enthesitis at the heel, n (%)

745 (69.5)

n=1072

625 (73.0)

n=856

120 (55.6)

n=216

csDMARD cotherapy, n (%)

392 (23.5)

274 (24.5)

118 (21.4)

 First line

1046 (62.7)

702 (62.9)

346 (62.8)

 Second line

389 (23.3)

261 (23.4)

128 (23.2)

 ≥Third line

233 (14.0)

154 (13.8)

77 (14.0)