Table 1 AxSpA characteristics of patients with and without self-reported psoriasis symptoms and with and without verified psoriasis diagnosis

Age (years)

52.2 ± 12.8

50.1 ± 12.7

52.2 ± 12.8

49.3 ± 13.0

55.0 ± 12.2

Sex (% male)

287 (64.1)

241 (62.3)

44 (75.9)*

19 (67.9)

25 (83.3)

HLA-B27 + 

339 (78.5)

294 (78.6)

43 (74.1)

19 (73.1)

24 (82.8)

Smoking

289 (67.4)

248 (67.0)

38 (65.5)

18 (69.2)

20 (66.7)

BMI, at baseline (kg/m²)

26.3 [23.4–29.1]

26.1 [23.2–29.1]

27.1 [25.3–30.1]*

27.9 [26.2–30.1]

26.6 [25.2–29.5]

Duration of SpA symptoms^a (years)

21.0 [12.0–32.0]

22.0 [12.0–32.8]

19.0 [9.0–33.0]

17.0 [6.0–29.0]

24.0 [14.0–41.0]

Age of onset SpA symptoms^a (years)

24.9 [19.5–33.1]

24.5 [19.0–32.3]

26.8 [21.3–37.1]

29.5 [23.3–35.5]

25.7 [20.0–37.9]

Anti-TNF history

252 (56.3)

212 (54.8)

37 (63.8)

18 (64.3)

19 (63.3)

History of IBD

46 (10.3)

34 (8.8)

11 (19.0)*

4 (14.3)

7 (23.3)

History of peripheral arthritis

161 (38.6)

134 (37.4)

25 (43.1)

11 (42.3)

14 (46.7)

History of uveitis^a

134 (29.9)

118 (30.5)

17 (29.3)

4 (14.3)

4 (13.3)

History of enthesitis

89 (20.0)

79 (20.6)

8 (13.8)

5 (17.9)

10 (33.3)

History of dactylitis

30 (6.8)

24 (6.2)

6 (10.3)

4 (14.3)

2 (6.7)

ASDAS_CRP

2.2 ± 1.0

2.2 ± 1.0

2.0 ± 1.0

1.9 ± 0.9

2.1 ± 1.0

BASDAI

3.7 ± 2.2

3.7 ± 2.2

3.7 ± 2.2

3.5 ± 2.2

3.8 ± 2.2

CRP

3 [2–6]

3 [2–6]

2.0 [1.0–5.0]*

2.0 [1.2–3.3]

2.0 [1.0–6.1]

ASQoL

4.5 [1–9]

4.4 [1–9]

5.6 [1.3–9.0]

3.8 [1.8–9.3]

7.0 [1.8–8.6]