Table 2.
General characteristics of patients with SpAs.
| Classical classification [2] | New classification [3, 4] | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| All (n = 144)a | AS (n = 80) |
PsA (n = 31) |
uSpA (n = 24) | IBD-associated SpA (n = 6) | P value | Axial (n = 89) | Peripheral (n = 55) | P value | |
| Mean (SD) | |||||||||
|
| |||||||||
| Age, years | 43.78 (11.08) | 42.23 (10.33) | 50.81 (13.00) | 41.28 (8.45) | 38.96 (6.02) | P < 0.05b, c | 41.80 (10.15) | 46.54 (11.84) | P = 0.018 |
| Age at onset, years | 34.77 (11.39) | 33.24 (10.71) | 41.23 (11.20) | 33.71 (11.52) | 29.33 (6.77) | P < 0.05b | 33.05 (10.42) | 37.62 (12.35) | P = 0.017 |
| Age at diagnostic, years | 39.24 (10.98) | 37.58 (10.27) | 45.65 (12.43) | 37.54 (9.31) | 34.17 (7.83) | P < 0.05b, c | 37.40 (10.03) | 42.00 (11.95) | P = 0.017 |
|
| |||||||||
| Characteristic, n (%) | |||||||||
|
| |||||||||
| Percentage | 100 | 55.6 | 21.5 | 16.7 | 4.2 | NA | 60.13 | 37.16 | NA |
| Maled | 82 (56.9) | 45 (56.3) | 20 (64.5) | 13 (54.2) | 2 (33.3) | NS | 51 (57.39) | 31 (56.4) | NS |
| Female | 62 (43.1) | 35 (43.8) | 11 (35.5) | 11 (45.8) | 4 (66.7) | NS | 38 (42.7) | 24 (43.6) | NS |
| Low back pain | 111 (77.1) | 80 (100) | 10 (32.3) | 15 (62.5) | 4 (66.7) | P < 0.001b, c, e | 89 (100) | 50 (90.9) | P < 0.001 |
| Peripheral arthritis | 73 (50.7) | 22 (27.5) | 24 (77.4) | 22 (91.7) | 3 (50) | P < 0.001b, c | 23 (25.8) | 50 (90.9) | P < 0.001 |
| Enthesitis (heel) | 26 (18.1) | 18 (22.5) | 2 (6.5) | 4 (16.7) | 2 (33.3) | NS | 20 (22.5) | 6 (10.9) | NS |
| Enthesitis (other sites) | 34 (23.6) | 19 (23.8) | 6 (16.1) | 8 (33.3) | 2 (33.3) | NS | 22 (24.7) | 12 (21.8) | NS |
| Dactylitis | 28 (19.4) | 10 (12.5) | 9 (29) | 8 (33.3) | 1 (16.7) | NS | 11 (12.4) | 17 (30.9) | P = 0.006 |
| Psoriasis | 28 (19.4) | 0 | 28 (90.3) | 0 | 0 | P < 0.001b, f, g | 2 (2.2) | 26 (47.3) | P < 0.001 |
| IBD | 6 (4.2) | 0 | 0 | 0 | 6 (100) | P < 0.001e, g, h | 2 (2.2) | 4 (7.3) | NS |
|
| |||||||||
| HLA-B27 | |||||||||
|
| |||||||||
| Positive | 43/86 (50) | 27/54 (50) | 2/11 (18.2) | 14/17 (82.35) | 0 | NA | 29/59 (49.15) | 14/27 (51.85) | NA |
| Negative | 43/86 (50) | 27/54 (50) | 9/11 (81.8) | 3/17 (17.65) | 2/2 (100) | NA | 30/59 (50.85) | 13/27 (48.15) | NA |
| No data available | 58/144 (40.3) | 26/80 (32.5) | 20/31 (64.5) | 7/24 (29.16) | 4/6 (66.66) | NA | 30/89 (33.7) | 28/55 (50.9) | NA |
AS: ankylosing spondylitis, PsA: psoriatic arthritis, uSpA: undifferentiated spondyloarthropatty, IBD: inflammatory bowel disease, ReA: reactive arthritis, AD: autoimmune disease, HLA: human leukocyte antigen, NA: not applicable, and NS: non significant.
aNeither ReA (n = 3) nor exclusive extraarticular SpA were included.
bSignificant differences between AS and PsA.
cSignificant differences between AS and uSpA.
dSignificant differences in gender for all categories.
eSignificant differences between AS and IBD-associated SpA.
fSignificant differences between PsA and uSpA.
gSignificant differences between PsA and IBD-associated SpA.
hSignificant differences between uSpA and IBD-associated SpA.