|
VS group (n = 31)
|
Non-VS group (n = 154)
|
P-value*
|
---|
Sex (male:female)
|
4:27
|
2:146
|
0.11
|
Age (years) (IQR)
|
67 (63−72)
|
68 (61−75)
|
0.36
|
Age of onset (years) (IQR)
|
48 (38−56)
|
55 (44−66)
|
< 0.01
|
RA duration (years) (IQR)
|
18 (13−25)
|
9 (4−21)
|
< 0.01
|
CRP level (mg/dL) (IQR)
|
0.7 (0.4−1.5)
|
0.3 (0.1−1.0)
|
< 0.01
|
RF positive (n)
|
55 % (17/31)
|
64 % (98/154)
|
0.36
|
MMP3 positive (n)
|
61 % (19/31)
|
66 % (102/154)
|
0.60
|
DAS28-CRP (IQR)
|
2.9 (2.2−3.6)
|
2.2 (1.7−3.0)
|
0.55
|
RA stage III or IV (n)
|
97 % (30/31)
|
64 % (99/154)
|
< 0.01
|
Prednisolone (n)
|
68 % (21/31)
|
45 % (69/154)
|
0.02
|
MTX (n)
|
52 % (16/31)
|
65 % (100/154)
|
0.16
|
Biological agents (n)
|
42 % (13/31)
|
28 % (43/154)
|
0.12
|
BMD of the lumbar spine (IQR)
|
79 % (74−92)
|
82 (71−93)
|
0.66
|
BMD of the femoral neck (IQR)
|
60 % (49–67)
|
68 (60–77)
|
0.04
|
Previous joint surgery (n)
|
68 % (21/31)
|
26 % (40/154)
|
< 0.01
|
- BMD bone mineral density, CRP C-reactive protein, DAS28-CRP Disease Activity Score based on C-reactive protein, MTX methotrexate, RA rheumatoid arthritis, VS vertical subluxation, IQR interquartile range
- *The P-value was calculated using the Fisher exact test, Mann−Whitney U test, and Student t-test, or chi-square test