Session Information
Date: Monday, November 6, 2017
Title: Spondyloarthropathies and Psoriatic Arthritis – Clinical Aspects and Treatment II
Session Type: ACR Concurrent Abstract Session
Session Time: 2:30PM-4:00PM
Background/Purpose:
Psoriatic arthritis (PsA) is clinically heterogeneous, with broad phenotypes of musculoskeletal (MSK) involvement including peripheral arthritis, enthesitis, dactylitis, and axial involvement. Sacroiliitis (SI) in PsA can be unilateral or bilateral in contrast with ankylosing spondylitis which appears to be commonly bilateral. It has been suggested that specific Human Leukocyte Antigen (HLA) allele can present with either unilateral or bilateral sacroillitis in PsA, HLA-B*27 with symmetrical SI, HLA-B*08 with unilateral or asymmetrical SI.
Our objectives were a) to determine the pattern of progression of sacroiliac joint involvement in PsA (unilateral versus bilateral; b) to determine the predictors of progression of sacroiliac joint involvement (symmetrical versus asymmetrical)
Methods:
A retrospective cohort analysis was conducted in patients followed in a large PsA clinic from 1978 to 2016. The participants were assessed at 6 to 12-month intervals according to a standard protocol. The collected information included demographics, medical history, radiological results, HLA allele, and PsA-related outcomes. Radiographs were performed at 2-year intervals. A statistical model was developed to assess for development of SI. Polychotomous logistic regression was used to assess the effect of HLA alleles.
Results:
A total of 1431 PsA patients were analysed. Three hundred and eight patients had SI (23%); 125 (9%) patients with unilateral SI; 17% of patients were HLA-B*27 positive, table 1. On analysis of the radiological result based on HLA alleles; 85 patients had bilateral asymmetrical SI, 29 (34%) were HLA-B*27 positive. 176 patients had symmetrical SI, 33 (22%) were HLA-B*27 positive. HLA-B*08 had similar proportion of patients in each category. In the bilateral SI group (20% in asymmetric, 16% in symmetric), 18% in the unilateral group. Interestingly, HLA-C*07 which has not been reported before accounted for more SI both in the unilateral and bilateral group, table 2.
Using polychotomus logistic regression, controlling for gender, HLA-B*27 positive patients had significantly higher odds of bilateral involvement compared to no sacroiliac joint involvement (OR = 2.42, 95% CI: 1.05, 5.56; p=0.038)
Conclusion:
HLA-B*27 is associated with bilateral sacroiliac joint involvement in PsA. Patients with HLA-C*07 are found to have more axial disease compared to the other HLA alleles.
References
1. Winchester R, et al. Clin Immunol. 2016 Nov; 172:29-33.
2. Haroon M, et al. Clin Exp Rheumatol. 2016 Dec 13.
|
Table 1: Patients characteristics |
||
|
Variable |
Overall (N=1431) |
|
|
Age |
53.8 |
(14.8) |
|
Female, n (%) |
634 |
(44%) |
|
Age at diagnosed, psoriasis |
28.8 |
(14.7) |
|
Age at diagnosis, psoriatic arthritis |
38.0 |
(13.6) |
|
Swollen joint count |
3.4 |
(4.9) |
|
Tender joint count |
7.1 |
(8.7) |
|
Total clinical damaged joint count |
2.6 |
(6.7) |
|
Body mass index (BMI) |
28.2 |
(7.8) |
|
Psoriasis area and severity index (PASI) |
3.8 |
(7.0) |
|
Modified Steinbroker score |
10.1 |
(22.9) |
|
Number of X-ray, median (min, max) |
2.0 |
(1.0, 17.0) |
|
Number of visit, median (min, max) |
6.0 |
(1.0, 66.0) |
|
Inflammatory back pain, n (%) |
214 |
(15%) |
|
Damaged joints, n (%) |
484 |
(34%) |
|
Dactylitis, n (%) |
403 |
(28%) |
|
Enthesitis, n (%) |
239 |
(17%) |
|
Nail lesion, n (%) |
949 |
(75%) |
|
HLA-B27 positive, n (%) |
188 |
(17%) |
|
Sacroiliitis, n (%) |
308 |
(23%) |
|
Radiographic unilateral >=2, n (%) |
125 |
(9%) |
|
Radiographic bilateral >=2, n (%) |
274 |
(19%) |
|
Radiographic damage, n (%) |
724 |
(54%) |
|
Table 2: HLA alleles and pattern of sacroillitis |
|||||||||||
|
Variable |
Bilateral-Asymmetric |
Bilateral-Symmetric |
None |
Progressive (from uni to bilateral) |
Unilateral |
|
|||||
|
B7, n (%) |
11 |
(13%) |
23 |
(16%) |
60 |
(16%) |
12 |
(14%) |
17 |
(17%) |
|
|
B8, n (%) |
17 |
(20%) |
24 |
(16%) |
65 |
(18%) |
21 |
(24%) |
19 |
(18%) |
|
|
B13, n (%) |
6 |
(7%) |
13 |
(9%) |
26 |
(7%) |
1 |
(1%) |
11 |
(11%) |
|
|
B14, n (%) |
4 |
(5%) |
10 |
(7%) |
34 |
(9%) |
6 |
(7%) |
10 |
(10%) |
|
|
B15, n (%) |
1 |
(1%) |
9 |
(6%) |
6 |
(2%) |
2 |
(2%) |
3 |
(3%) |
|
|
B18, n (%) |
3 |
(4%) |
13 |
(9%) |
30 |
(8%) |
5 |
(6%) |
6 |
(6%) |
|
|
B27, n (%) |
29 |
(34%) |
33 |
(22%) |
42 |
(12%) |
14 |
(16%) |
18 |
(17%) |
|
|
B35, n (%) |
11 |
(13%) |
20 |
(14%) |
63 |
(17%) |
14 |
(16%) |
6 |
(6%) |
|
|
B37, n (%) |
1 |
(1%) |
5 |
(3%) |
12 |
(3%) |
2 |
(2%) |
3 |
(3%) |
|
|
B38, n (%) |
15 |
(18%) |
21 |
(14%) |
48 |
(13%) |
13 |
(15%) |
12 |
(12%) |
|
|
B39, n (%) |
8 |
(9%) |
12 |
(8%) |
19 |
(5%) |
8 |
(9%) |
4 |
(4%) |
|
|
B44, n (%) |
15 |
(18%) |
32 |
(22%) |
79 |
(22%) |
13 |
(15%) |
19 |
(18%) |
|
|
B45, n (%) |
0 |
(0%) |
0 |
(0%) |
3 |
(1%) |
0 |
(0%) |
1 |
(1%) |
|
|
B50, n (%) |
2 |
(2%) |
1 |
(1%) |
10 |
(3%) |
1 |
(1%) |
2 |
(2%) |
|
|
B51, n (%) |
5 |
(6%) |
9 |
(6%) |
19 |
(5%) |
4 |
(5%) |
8 |
(8%) |
|
|
B52, n (%) |
1 |
(1%) |
3 |
(2%) |
18 |
(5%) |
7 |
(8%) |
5 |
(5%) |
|
|
B55, n (%) |
4 |
(5%) |
2 |
(1%) |
9 |
(2%) |
3 |
(3%) |
3 |
(3%) |
|
|
B56, n (%) |
0 |
(0%) |
3 |
(2%) |
4 |
(1%) |
1 |
(1%) |
1 |
(1%) |
|
|
B57, n (%) |
11 |
(13%) |
18 |
(12%) |
44 |
(12%) |
18 |
(21%) |
17 |
(17%) |
|
|
B60, n (%) |
4 |
(5%) |
11 |
(7%) |
20 |
(5%) |
5 |
(6%) |
4 |
(4%) |
|
|
B61, n (%) |
3 |
(4%) |
5 |
(3%) |
9 |
(2%) |
2 |
(2%) |
2 |
(2%) |
|
|
B62, n (%) |
3 |
(4%) |
5 |
(3%) |
25 |
(7%) |
6 |
(7%) |
8 |
(8%) |
|
|
C1, n (%) |
11 |
(13%) |
19 |
(13%) |
32 |
(9%) |
9 |
(10%) |
11 |
(11%) |
|
|
C2, n (%) |
20 |
(24%) |
24 |
(16%) |
27 |
(7%) |
7 |
(8%) |
14 |
(14%) |
|
|
C3, n (%) |
11 |
(13%) |
21 |
(14%) |
71 |
(20%) |
13 |
(15%) |
17 |
(17%) |
|
|
C4, n (%) |
13 |
(15%) |
20 |
(14%) |
74 |
(20%) |
19 |
(22%) |
10 |
(10%) |
|
|
C6, n (%) |
18 |
(21%) |
41 |
(28%) |
90 |
(25%) |
21 |
(24%) |
34 |
(33%) |
|
|
C7, n (%) |
34 |
(40%) |
64 |
(43%) |
167 |
(46%) |
38 |
(44%) |
49 |
(48%) |
|
|
C8, n (%) |
5 |
(6%) |
12 |
(8%) |
34 |
(9%) |
7 |
(8%) |
10 |
(10%) |
|
|
C12, n (%) |
25 |
(30%) |
34 |
(23%) |
74 |
(20%) |
24 |
(28%) |
19 |
(18%) |
|
|
C14, n (%) |
1 |
(1%) |
3 |
(2%) |
8 |
(2%) |
3 |
(3%) |
3 |
(3%) |
|
|
C15, n (%) |
8 |
(10%) |
4 |
(3%) |
13 |
(4%) |
4 |
(5%) |
3 |
(3%) |
|
|
C16, n (%) |
6 |
(7%) |
10 |
(7%) |
27 |
(7%) |
0 |
(0%) |
5 |
(5%) |
|
To cite this abstract in AMA style:
Elmamoun M, Ye J, Cook RJ, Chandran V, Gladman DD. Patterns and Predictors of Progression of Sacroiliitis in Psoriatic Arthritis and Its Relationship with Human Leukocyte Antigen (HLA) Alleles. Results from the Toronto Cohort [abstract]. Arthritis Rheumatol. 2017; 69 (suppl 10). https://acrabstracts.org/abstract/patterns-and-predictors-of-progression-of-sacroiliitis-in-psoriatic-arthritis-and-its-relationship-with-human-leukocyte-antigen-hla-alleles-results-from-the-toronto-cohort/. Accessed .ACR Meeting Abstracts - https://acrabstracts.org/abstract/patterns-and-predictors-of-progression-of-sacroiliitis-in-psoriatic-arthritis-and-its-relationship-with-human-leukocyte-antigen-hla-alleles-results-from-the-toronto-cohort/