Which MRI Lesions in the Sacroiliac Joint Are Associated with the Diagnosis of Axial Spondyloarthritis after 2 Years Follow up in the Echography in Spondyloarthritis Cohort?

Walter P. Maksymowych^1,2, Damien Loeuille³, Stephanie Wichuk⁴, Joel Paschke⁵, Olivia Judet⁶, Maxime Breban³, Maria-Antonietta D'Agostino⁷ and Robert G. Lambert⁸, ¹University of Alberta, Edmonton, AB, Canada, ²CaRE Arthritis, Edmonton, AB, Canada, ³Ambroise Paré Hospital, Boulogne-Billancourt, France, ⁴Medicine, Medicine, University of Alberta, Edmonton, AB, Canada, ⁵CaRE Arthritis, Edmonton, Canada, Edmonton, AB, Canada, ⁶CHRU Vandoeuvre les Nancy, Vandœuvre-lès-Nancy, France, ⁷CHRU Vandoeuvre les Nancy, Vandoeuvre les Nancy, France, ⁸Radiology, Radiology, University of Alberta, Edmonton, AB, Canada

Meeting: ACR/ARHP Annual Meeting 2018

Keywords: diagnosis and spondylarthritis, MRI

Session Information

Date: Wednesday, October 24, 2018

Title: 6W011 ACR Abstract: Spondyloarthritis Incl PsA–Clinical VI: Imaging of Axial SpA (2922–2927)

Session Type: ACR Concurrent Abstract Session

Session Time: 9:00AM-10:30AM

Background/Purpose:

MRI of the sacroiliac joint (SIJ) is emerging as an important prognostic tool for assessment of patients presenting with axSpA. A major challenge in the evaluation of early SpA is establishing the diagnosis and this requires prospective follow up to determine which cases have developed axSpA with more certainty. We aimed to assess the baseline distribution and prognostic capacity of MRI lesions in the SIJ of patients diagnosed with axSpA after 2 years follow up in the ECHOSPA cohort.

Methods:

Consecutive outpatients with age <50 years and symptoms >3 months suggestive of SpA (inflammatory back pain [IBP], peripheral arthritis or inflammatory arthralgia (IA), enthesitis or dactylitis, uveitis with HLA–B27 positivity, a family history of SpA were enrolled. The diagnosis of SpA was ascertained by an expert committee, blind to MRI evaluation, after at least 2 years of follow-up. MRI scans from 223 cases were available for evaluation by 2 readers and an adjudicator who assessed MRI lesions in the SIJ according to updated consensus definitions from the ASAS-MRI group. These were recorded in an ASAS consensus-derived eCRF that comprises global assessment (active and/or structural lesion typical of axSpA present/absent) and detailed scoring of individual lesions (SPARCC SIJ inflammation, SPARCC SIJ structural). Clinical, lab, and imaging variables associated with the diagnosis of axSpA at 2 years were first identified by univariate regression. A base model of all clinical/lab variables associated with axSpA was included as a group in multivariate logistic regression models that tested the independent association with MRI lesions.

Results:

Mean age of the 223 cases was 39.6 (10.5) years, mean symptom duration was 2.5 (4.1) years, 49.5% were HLA-B27+ and 63.7% were female. Primary inclusion criterion was IBP in 53%, IA in 27%, ED in 9%, B27+U in 8% and Fam in 4%. At 2 years follow up, 165 (74%) were deemed to have axSpA. In group comparisons (Table) and univariate regression, both active and structural MRI lesions were associated with diagnosis of axSpA at 2 years (p=0.03, p=0.01, respectively). Age, B27, and psoriasis were the clinical variables associated with diagnosis of axSpA at 2 years in univariate analysis (all p<0.0001) and were included together with gender in multivariate analyses. Active and structural lesions typical of axSpA and SPARCC BME score ≥2 were each independently associated with diagnosis of axSpA at 2 years (OR(95%CI)- 6.8(1.4-34.1) (p=0.02); 17.9(2.2-146.6) (p=0.007); 4.9(1.3-18.4) (p=0.02). With all variables simultaneously added to the model, only structural lesions were significantly associated.

Conclusion:

Assessment of both active and structural lesions on MRI may help determine which patients have axSpA with higher diagnostic certainty over time.

Table. Distribution of MRI lesions at baseline according to diagnosis of axSpA after 2 years.

MRI Lesion	AxSpA n=165 (74.0%)	NOT SpA n=58 (26.0%)	P value
Active lesion typical for axSpA	26 (16.0%)	2 (3.6%)	0.019
Active lesion typical for axSpA (confidence ≥3, 0-4 scale)	18 (11.9%)	1(1.8%)	0.027
ASAS MRI positivity	24 (14.6%)	1 (1.7%)	0.006
ASAS MRI positivity (confidence ≥3, 0-4 scale)	17 (10.8%)	1(1.7%)	0.048
Structural lesion typical for axSpA	32(19.6%)	1 (1.8%)	0.0004
Structural lesions typical for axSpA (confidence ≥3, 0-4 scale)	27 (17.3%)	0 (0%)	0.0002
Active AND structural lesion typical for axSpA	19 (11.7%)	0 (0%)	0.004
Active OR structural lesion typical for axSpA	39 (23.9%)	3 (5.4%)	0.001
Only active lesion typical of axSpA	7 (4.3%)	2 (3.6%)	1.0
Only structural lesion typical of axSpA	13 (8.0%)	1 (1.8%)	0.12

Disclosure: W. P. Maksymowych, CaRE rthritis, 9; D. Loeuille, None; S. Wichuk, None; J. Paschke, None; O. Judet, None; M. Breban, None; M. A. D'Agostino, None; R. G. Lambert, None.

To cite this abstract in AMA style:

Maksymowych WP, Loeuille D, Wichuk S, Paschke J, Judet O, Breban M, D'Agostino MA, Lambert RG. Which MRI Lesions in the Sacroiliac Joint Are Associated with the Diagnosis of Axial Spondyloarthritis after 2 Years Follow up in the Echography in Spondyloarthritis Cohort? [abstract]. Arthritis Rheumatol. 2018; 70 (suppl 9). https://acrabstracts.org/abstract/which-mri-lesions-in-the-sacroiliac-joint-are-associated-with-the-diagnosis-of-axial-spondyloarthritis-after-2-years-follow-up-in-the-echography-in-spondyloarthritis-cohort/. Accessed .

ACR Meeting Abstracts - https://acrabstracts.org/abstract/which-mri-lesions-in-the-sacroiliac-joint-are-associated-with-the-diagnosis-of-axial-spondyloarthritis-after-2-years-follow-up-in-the-echography-in-spondyloarthritis-cohort/