|
Characteristic
|
Psoriatic arthritis
|
Rheumatoid arthritis (group I)
|
Matched rheumatoid arthritis (group II)
|
Controls
|
|---|
|
Number of patients
|
15
|
49
|
30
|
8
|
|
Age (years)
|
55.7 ± 10.7
|
57.6 ± 14.6
|
56.3 ± 16.3
|
38.1 ± 21.9
|
|
Sex (women/men)*
|
8/7
|
42/7
|
20/10
|
4/4
|
|
Disease duration (months)
|
63.5 ± 62.7
|
93.5 ± 98.7
|
78.2 ± 86.2
|
NA
|
|
Morning stiffness (minutes)
|
70.4 ± 55.7
|
96.2 ± 96.3
|
76.8 ± 92.1
|
NA
|
|
Number of tender joints*
|
8.0 ± 5.5
|
13.7 ± 9.4
|
9.1 ± 7.3
|
0
|
|
Number of swollen joints
|
5.3 ± 4.4
|
8.0 ± 5.8
|
5.0 ± 3.9
|
0
|
|
Ritchie index
|
8.3 ± 5.7
|
11.6 ± 6.9
|
7.0 ± 5.1
|
0
|
|
ESR (mm/h)
|
34.7 ± 21.8
|
49.1 ± 31.6
|
45.5 ± 35.7
|
ND
|
|
CRP (mg/l)
|
30.4 ± 39.4
|
30.3 ± 34.4
|
26.6 ± 36.1
|
ND
|
|
Number of patients with IgM rheumatoid factor**
|
1 (6.7%)
|
33 (67.3%)
|
18 (60%)
|
ND
|
|
Rate of early enhancement§
|
1.0 ± 0.6
|
1.6 ± 0.7
|
1.3 ± 0.7
|
0.1 ± 0.1
|
|
Relative enhancement §
|
87.1 ± 39.2
|
125.8 ± 48.0
|
107.3 ± 48.2
|
15.5 ± 19.2
|
- Values are expressed as means ± standard deviations except for sex and IgM rheumatoid factor, for which the percentage of positive patients is reported. *P < 0.05 for the comparison between PsA and groupI RA; **P < 0.001 for the comparison between PsA and groupI RA and P < 0.05 for the comparison between PsA and groupII RA; §P < 0.001 by one-way analysis of variance between PsA patients, groupI RA patients, and controls.
