Age (years)
|
35 ± 9
|
34 ± 10
|
38 ± 8
|
0.075
|
Male sex
|
91 (77)
|
74 (76)
|
17 (77)
|
1.000
|
BMI (kg/m2)
|
23.2 ± 3.4
|
22.9 ± 3.2
|
24.4 ± 4.1
|
0.072
|
Current smoking
|
36 (30)
|
25 (26)
|
11 (50)
|
0.038
|
Alcohol ≥ 3 units/day
|
3 (3)
|
3 (3)
|
0 (0)
|
1.000
|
Symptom duration (years)
|
8.6 ± 7.6
|
7.9 ± 7.3
|
11.6 ± 8.0
|
0.035
|
Family history of axSpA
|
12 (10)
|
12 (12)
|
0 (0)
|
0.120
|
HLA B27-positive
|
110 (92)
|
90 (93)
|
20 (91)
|
0.671
|
Peripheral arthritis
|
27 (23)
|
22 (23)
|
5 (23)
|
1.000
|
Radiographic sacroiliitis
|
90 (76)
|
70 (72)
|
20 (91)
|
0.097
|
BASDAI score (range 0–10)
|
3.9 ± 2.1
|
3.9 ± 2.0
|
3.7 ± 2.7
|
0.683
|
BASFI score
|
1.7 ± 2.1
|
1.7 ± 2.2
|
1.8 ± 1.8
|
0.722
|
ESR (mm/h)
|
23 ± 20
|
23 ± 20
|
23 ± 19
|
0.960
|
CRP (mg/L)
|
9.1 ± 14.9
|
8.9 ± 15.2
|
10.2 ± 14.1
|
0.703
|
ASDAS-ESR
|
2.6 ± 1.1
|
2.6 ± 1.1
|
2.5 ± 1.3
|
0.707
|
ASDAS-CRP
|
2.2 ± 1.3
|
2.2 ± 1.2
|
2.2 ± 1.5
|
0.883
|
mSASSS
|
7.6 ± 14.3
|
5.7 ± 13.0
|
15.8 ± 17.1
|
0.015
|
Number of syndesmophytes
|
2.3 ± 4.8
|
1.6 ± 4.3
|
5.0 ± 6.0
|
0.021
|
Presence of syndesmophytes
|
34 (29)
|
21 (22)
|
13 (59)
|
0.001
|
Patients on NSAIDs
|
106 (89)
|
86 (89)
|
20 (91)
|
1.000
|
Patients on sulfasalazine
|
42 (35)
|
34 (35)
|
8 (36)
|
1.000
|
Patients on TNF inhibitors
|
36 (30)
|
27 (28)
|
9 (41)
|
0.303
|
Patients on bisphosphonate
|
2 (2)
|
2 (2)
|
0 (0)
|
1.000
|
Patients on calcium
|
17 (14)
|
11 (11)
|
6 (27)
|
0.085
|
Patients on vitamin D
|
18 (15)
|
12 (12)
|
6 (27)
|
0.099
|
BMD (g/cm2)
|
Lumbar spine
|
1.16 ± 0.17
|
1.17 ± 0.16
|
1.13 ± 0.22
|
0.949
|
Femoral neck
|
0.94 ± 0.14
|
0.94 ± 0.14
|
0.92 ± 0.16
|
0.401
|
Total hip
|
0.98 ± 0.15
|
0.99 ± 0.15
|
0.95 ± 0.15
|
0.338
|
Low BMD (Z score ≤ −2.0)
|
Any site
|
19 (16)
|
12 (12)
|
7 (32)
|
0.047
|
Lumbar spine
|
15 (13)
|
10 (10)
|
5 (23)
|
0.150
|
Femoral neck
|
3 (3)
|
1 (1)
|
2 (12)
|
0.070
|
Total hip
|
5 (4)
|
3 (3)
|
2 (9)
|
0.233
|