Session Information
Date: Monday, November 9, 2015
Title: Spondylarthropathies and Psoriatic Arthritis - Comorbidities and Treatment Poster II
Session Type: ACR Poster Session B
Session Time: 9:00AM-11:00AM
Background/Purpose: Magnetic resonance imaging of sacroiliac joints (MRI-SI) and HLA-B27 testing are important tools in the diagnosis of spondyloarthritis (SpA). The aim of the study was to evaluate the patient´s characteristics associated with the clinical decision to request MRI-SI and/or HLA-B27 in daily practice
Methods: A cohort of patients referred to a specialised rheumatology outpatient clinic in a national referral centre was used. Data related to age, gender, number of initial symptom at presentation (arthritis and/or enthesitis and/or back pain and/or buttock pain), disease duration, infection history, past and currently present SpA features (chronic back pain, inflammatory back pain (IBP), asymmetric oligoarthritis, enthesitis (heel pain), dactylitis, buttock pain, uveitis, psoriasis and inflammatory bowel disease) were collected from the clinical record. BASDAI and ASDAS were calculated. Patients with the clinical diagnosis of SpA according to the rheumatologist were included. Information on MRI-SI and HLA-B27 was available only for those patients for whom the rheumatologists decided to order these tests. Characteristics associated with ordering MRI-SI or HLA-B27 separately were identified with univariable analyses. Variables with a p-value <0.05 and data available over 80% of cases were entered in the (backward) multivariable analysis. Colinearity and interactions were checked and relevant interactions were excluded A multivariable logistic regression analysis was used to evaluate factors related with the decision to perform MRI-SI and/or HLA-B27 and odds ratios (95% CI) were calculated
Results: In total, 581 patients with SpA were included, 72% were men, with a mean age of 34.6±12.1 years, age at symptom onset of 28,0±10.3 years and disease duration of 7.3±9.7 years. Disease activity was calculated separately for axial and peripheral SpA and was rather high for both: BASDAI: 5.4 (2.4) and ASDAS-ESR: 3 (0.9). For axial SpA ASDAS-CRP was 2.6 (0.8) and for peripheral SpA was 2.3 (0.9). Of these patients, 24% (n=137) had MRI-SI and 77% (n=441) had HLA-B27 testing ordered. Predictive factors for ordering a MRI-SI were IBP (OR=1.81), enthesitis (OR=1.57) and the number of initial symptoms at presentation (OR=1.27). Predictive factors of HLA-B27 testing were the number of initial symptoms at presentation (OR=1.45) and uveitis (OR=3.19) Table1
Conclusion: IBP, enthesitis, and the number of symptoms at presentation were independently associated with ordering an MRI-SI. The number of symptoms at presentation and to some extent uveitis were associated with the request of HLA-B27. This study provides insight in characteristics that prompt rheumatologists to order complementary imaging or HLA-B27 testing in the diagnostic work-up of patients with SpA
Table 1. Association of SpA disease characteristics that independently prompt to ordering MRI-SI and HLA-B27. Results from a multivariable logistic regression model.
|
Explanatory variables |
MRI-SI ordered |
HLA-B27 ordered |
||
|
OR (95% CI) |
p Value |
OR (95% CI) |
p Value |
|
|
Male gender |
0.79 (0.50-1.22) |
0.28 |
0.85 (0.53-1.36) |
0.50 |
|
Number of symptoms at presentation (0-4) |
1.27 (1.10-1.47) |
≤0.001 |
1.45 (1.24-1.71) |
≤0.001 |
|
Disease duration |
0.90 (0.57-1.41) |
0.66 |
1.26 (0.77-2.04) |
0.34 |
|
Chronic back pain |
1.57 (0.72-3.23) |
0.26 |
0.96 (0.53-1.73) |
0.90 |
|
Inflammatory back pain |
1.81 (1.13-2.90) |
0.01 |
1.14 (0.70-1.85) |
0.58 |
|
Arthritis |
0.85 (0.54-1.33) |
0.48 |
1.15 (0.70-1.89) |
0.55 |
|
Enthesitis |
1.57 (1.00-2.49) |
0.04 |
0.89 (0.58-1.38) |
0.62 |
To cite this abstract in AMA style:
Bautista-Molano W, Landewé R, Serna C, Valle RR, van der Heijde D. Factors Associated with the Decision of the Rheumatologist to Order Sacro-Iliac Joints Magnetic Resonance Imaging (SI-MRI) or Order HLA-B27 Testing in Patients with Spondyloarthritis in Clinical Practice [abstract]. Arthritis Rheumatol. 2015; 67 (suppl 10). https://acrabstracts.org/abstract/factors-associated-with-the-decision-of-the-rheumatologist-to-order-sacro-iliac-joints-magnetic-resonance-imaging-si-mri-or-order-hla-b27-testing-in-patients-with-spondyloarthritis-in-clinical-pract/. Accessed .« Back to 2015 ACR/ARHP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/factors-associated-with-the-decision-of-the-rheumatologist-to-order-sacro-iliac-joints-magnetic-resonance-imaging-si-mri-or-order-hla-b27-testing-in-patients-with-spondyloarthritis-in-clinical-pract/