Zineb Ez-Zaitouni

Presence of multiple spondyloarthritis (SpA) features is important but not sufficient for a diagnosis of axial spondyloarthritis: data from the SPondyloArthritis Caught Early (SPACE) cohort

Objectives Concerns have been raised about overdiagnosis of axial spondyloarthritis (axSpA). We investigated whether patients with chronic back pain (CBP) of short duration and multiple SpA features are always diagnosed with axSpA by the rheumatologist, and to what extent fulfilment of the Assessment of SpondyloArthritis International Society (ASAS) axSpA criteria is associated with an axSpA diagnosis. Methods Baseline data from 500 patients from the SPondyloArthritis Caught Early cohort which includes patients with CBP (≥3 months, ≤2 years, onset <45 years) were analysed. All patients underwent full diagnostic workup including MRI of the sacroiliac joints (MRI-SI) and radiograph of sacroiliac joints (X-SI). For each patient, the total number of SpA features excluding sacroiliac imaging and human leucocyte antigen B27 (HLA-B27) status was calculated. Results Before sacroiliac imaging and HLA-B27 testing, 32% of patients had ≤1 SpA feature, 29% had 2 SpA features, 16% had 3 SpA features and 24% had ≥4 SpA features. A diagnosis of axSpA was made in 250 (50%) of the patients: 24% with ≤1 SpA feature, 43% with 2 SpA features, 62% with 3 SpA features and 85% with ≥4 SpA features. Of the 230 patients with a positive ASAS classification 40 (17.4%) did not have a diagnosis of axSpA. HLA-B27 positivity (OR 5.6; 95% CI 3.7 to 8.3) and any (MRI-SI and/or X-SI) positive imaging (OR 34.3; 95% CI 17.3 to 67.7) were strong determinants of an axSpA diagnosis. Conclusions In this cohort of patients with CBP, neither the presence of numerous SpA features nor fulfilment of the ASAS classification criteria did automatically lead to a diagnosis axSpA. Positive imaging was considered particularly important in making a diagnosis of axSpA.

Does body mass index (BMI) influence the Ankylosing Spondylitis Disease Activity Score in axial spondyloarthritis?: Data from the SPACE cohort.

Objective Obesity is associated with elevated C reactive protein (CRP) levels. The Ankylosing Spondylitis Disease Activity Score (ASDAS) combines patient-reported outcomes (PROs) and CRP. We evaluated the effect of body mass index (BMI) on CRP and on ASDAS, and studied if ASDAS can be used in obese axial spondyloarthritis (axSpA) patients to assess disease activity. Methods Baseline data of patients with chronic back pain of short duration included in the SPondyloArthritis Caught Early (SPACE) cohort were used. Collected data included BMI and ASDAS. Patients were classified according to the ASAS axSpA classification criteria and BMI (overweight ≥25 and obese ≥30). Correlation and linear regression analyses were performed to assess the relation between BMI and ASDAS. Linear regression models were performed to assess if age or gender were effect modifiers in the relation between BMI and CRP, and between BMI and ASDAS. Results In total, 428 patients were analysed (n=168 axSpA; n=260 no-axSpA). The mean age was 31.1 years, 36.9% were male, 26.4% were overweight and 13.3% obese, median CRP was 3 mg/L and the mean ASDAS was 2.6. Gender was the only factor modifying the relationship between BMI and CRP as BMI had an influence on CRP only in females (β=0.35; p<0.001). Correlations between BMI and CRP or PROs were generally weak, and only significant for CRP in female patients. BMI was not related to ASDAS in axSpA patients. Conclusions ASDAS is not affected by BMI in axSpA patients. Therefore, based on our data it is not necessary to take BMI in consideration when assessing disease activity using ASDAS in axSpA patients.

Patients aged 16-45 years with chronic back pain of a short duration and maximally 1 SpA-feature: Are additional tests needed to rule out axial spondyloarthritis? (results from the SPACE cohort).

To investigate whether HLA–B27 testing and imaging of the sacroiliac joints are needed in patients with ≤1 spondyloarthritis (SpA) feature, referred to a secondary care setting, after medical history collection, clinical examination, and measurement of acute phase reactants.

Are Additional Tests Needed to Rule Out Axial Spondyloarthritis in Patients Ages 16–45 Years With Short‐Duration Chronic Back Pain and Maximally One Spondyloarthritis Feature?

To investigate whether HLA–B27 testing and imaging of the sacroiliac joints are needed in patients with ≤1 spondyloarthritis (SpA) feature, referred to a secondary care setting, after medical history collection, clinical examination, and measurement of acute phase reactants.

FRI0514 Adding Mri of The Spine To The Asas Classification Criteria for Axial Spondyloarthritis, Redundant or Beneficial? Data from The Spondyloarthritis Caught Early (Space)-Cohort

Background The ASAS definition of a positive MRI is solely based on inflammation in the sacroiliac joints (SIJ), although spinal inflammatory lesions on MRI suggestive of axial Spondyloarthritis (axSpA) may also occur. It is not well known how often inflammation in the spine occurs in absence of inflammation in the SIJ and consequently what the utility is of including inflammation in the spine in the definition of a positive MRI. Objectives To analyze the prevalence of spinal inflammation on MRI in patients with chronic back pain (CBP) at baseline and one-year follow-up, and to evaluate the yield of adding MRI-spine as imaging criterion to the ASAS classification criteria for axial SpA. Methods The SPACE-cohort includes patients with CBP (≥3 months, ≤2 years, onset <45 years) from five participating centres in Europe. All available baseline (BL) and one-year follow-up (FU) MRI of SIJ and spine were scored by 2 well-calibrated readers. MRI-SI were scored according to the ASAS definition. Bone marrow oedema suggestive of axSpA was assessed in the entire spine and only counted if visible on ≥2 consecutive slices. To define a positive MRI-spine, two cut-off values were used: ≥3 inflammatory lesions (ASAS consensus definition) and ≥5 inflammatory lesions (defined as the best cut-off in earlier analyses). Adjudication for the ASAS definition by an experienced reader was performed in case of disagreement and all modalities were considered positive if 2/3 readers agreed. Results All patients with both MRI-spine and MRI-SIJ available at BL (n=329) and FU (n=168) were included in the analyses. At BL 43/329 (13.1%) of patients had a positive MRI-SIJ, of which 7/43 (16.3%) patients had a positive MRI-spine (ASAS consensus definition, ≥3 inflammatory lesions) and 2/43 (4.7%) if defined by ≥5 inflammatory lesions. Positive MRI-SIJ at FU was seen in 28/168 (16.7%) patients, 14 of which were also positive at BL; MRI-spine positivity was identified in 2/28 (7.1%) and 1/28 (3.6%) patients for the ASAS definition defined by ≥3 and ≥5 inflammatory lesions, respectively. In total, 4 patients had a positive MRI-spine and a negative MRI-SIJ: at BL 2 patients according to the ASAS definition of whom 1 also fulfilled the alternative definition. At FU this was 2 (different patients than at baseline) and 0 patients, respectively. Addition of MRI-spine to the classification criteria by the ASAS definition of ≥3 inflammatory lesions would lead to classification of 3 additional patients via imaging arm, with 1 patient already fulfilling the clinical arm. Conclusions In this cohort, a positive MRI-spine in the absence of sacroiliitis on MRI was rarely seen Addition of MRI-spine as an imaging criterion to the ASAS criteria had a low yield in number of classifications. Therefore, performing MRI of the spine at either baseline or one-year follow-up is of little value in patients with short duration of CBP and suspicion of axial SpA. Disclosure of Interest None declared

Impact of replacing radiographic sacroiliitis by magnetic resonance imaging structural lesions on the classification of patients with axial spondyloarthritis

Objectives To investigate in patients with chronic back pain of a short duration, the utility of adding structural MRI lesions of the SI joints to the imaging criterion of the Assessment of SpondyloArthritis International Society (ASAS) axial SpA (axSpA) criteria and the utility of replacement of radiographic sacroiliitis by structural MRI lesions. Methods MRI STIR (inflammation, MRI-SI), MRI T1-weighted images (structural lesions, MRI-SI-s) and radiographs of the SI joints of patients in the SPondyloArthritis Caught Early-cohort (chronic back pain: ⩾3 months, ⩽2 years; onset <45 years) were scored by two well-calibrated readers. Previously proposed cut-offs for a positive MRI-SI-s were used (based on <5% prevalence in no-SpA patients): erosions ⩾3, fatty lesions ⩾3, fatty lesions and/or erosions (erosions/fatty lesions) ⩾5. Using the definitions of MRI-SI-s, patients were classified according to the ASAS axSpA criteria. Results Twenty-nine of 294 patients were modified New York (mNY) positive and 32 were MRI-SI-s positive (erosions/fatty lesions ⩾5). Agreement between mNY and MRI-SI-s (erosions/fatty lesions ⩾5) was moderate (κ: 0.58). Using the erosions/fatty lesions ⩾5 cut-off, 3/294 additional patients were classified as axSpA (adding MRI). Using this cut-off instead of mNY (replacing mNY), classification did not change in 286 patients (97.3%), but 5 patients (1.7%) would not be classified as axSpA and 3 previously unclassified patients (1.0%) would be classified as axSpA. Similar results were seen for the other cut-offs (erosions ⩾3 and fatty lesions ⩾3). Conclusion Assessment of structural lesions (fatty lesions and erosions) on MRI-SI instead of or in addition to conventional radiographs does not lead to a different ASAS axSpA classification in most of the patients with early disease onset. This suggests that structural lesions (fatty lesions and erosions) can be reliably used in the ASAS axSpA classification of patients, as both addition and replacement of radiographs of the SI joints.

The impact of illness perceptions and coping on the association between back pain and health outcomes in patients suspected of axial spondyloarthritis: data from the SPACE cohort

To investigate whether illness perceptions and coping influence the relationship between back pain and health outcomes in patients suspected of having axial spondyloarthritis (SpA).

Disease activity decrease is associated with improvement in work productivity over 1 year in early axial spondyloarthritis (SPondyloArthritis Caught Early cohort)

Objectives To assess if a change in disease activity is associated with a change in work productivity loss (WPL) over 1 year in early axial SpA (axSpA) patients. Methods Baseline and 1 year data of axSpA patients in the SPondyloArthritis Caught Early cohort were analysed. Linear regression models were built explaining the change in the Ankylosing Spondylitis Disease Activity Score (ASDAS) over time by the change in absenteeism, presenteeism, WPL and activity impairment over time. Effect modification and confounding were tested for age, gender, arm of Assessment of SpondyloArthritis international Society classification criteria, HLA-B27, duration of chronic back pain, profession and medication. Results At baseline, in 105 axSpA patients (48% female, mean age 30.8 years, mean symptom duration 13.6 months, 92% HLA-B27 positive, 24% radiographic sacroiliitis), the mean ASDAS was 2.4 (s.d. 1.0), absenteeism 9% (s.d. 23), presenteeism 33% (s.d. 28), WPL 36% (s.d. 30) and activity impairment 37% (s.d. 25). After 1 year, the mean ASDAS decreased to 2.0 (s.d. 0.8) and absenteeism, presenteeism, WPL and activity impairment improved to 6% (s.d. 22), 26% (s.d. 26), 27% (s.d. 29) and 27% (s.d. 26), respectively. Models showed that if ASDAS decreased 1 unit, absenteeism, presenteeism, WPL and activity impairment improved by 5, 17, 16 and 18%, respectively. The impact of disease activity on work productivity was higher in patients with shorter symptom duration and the impact on absenteeism was higher in patients starting pharmacological treatment. Conclusions In early axSpA patients, work productivity and daily activities are seriously impacted at baseline and 1 year. However, decreasing disease activity is associated with marked improvements in work productivity and daily activities.

Is the current ASAS expert definition of a positive family history useful in identifying axial spondyloarthritis? Results from the SPACE and DESIR cohorts

BackgroundThe Assessment of SpondyloArthritis international Society (ASAS) definition of a positive family history (PFH) of spondyloarthritis (SpA) includes the following diseases in first- or second-degree relatives: ankylosing spondylitis (AS), acute anterior uveitis (AAU), reactive arthritis (ReA), inflammatory bowel disease (IBD), and psoriasis. However, it is not known if a PFH for each of these diseases contributes to making a diagnosis of axSpA, sacroiliitis on imaging, or fulfilling the ASAS criteria in patients presenting with chronic back pain (CBP). Therefore, the aim of this study was to assess which SpA diseases in family members are associated with human leukocyte antigen B27 (HLA-B27) and axial spondyloarthritis (axSpA) in CBP patients.MethodsCBP patients suspected of axSpA from the SPACE (n = 438) and the DESIR (n = 647) cohort were asked about the presence of SpA diseases in first- or second-degree relatives (AS, AAU, ReA, IBD, and psoriasis). The associations between a PFH and HLA-B27, sacroiliitis on imaging (magnetic resonance imaging (MRI) or radiographs), axSpA diagnosis, and ASAS classification in CBP patients were assessed.ResultsIn the SPACE and the DESIR cohort, a PFH of AS (odds ratio (OR) 5.9 (95% confidence interval (CI) 3.5–9.9), and OR 3.3 (95% CI 2.1–5.2)) and a PFH of AAU (OR 9.8 (95% CI 3.3–28.9) and OR 21.6 (95% CI 2.9–160.1)) were significantly associated with presence of HLA-B27. Furthermore, in both cohorts a PFH of AS and a PFH of AAU were positively associated with fulfilment of the ASAS criteria, but not with sacroiliitis on imaging. In SPACE but not in DESIR a PFH of AAU was positively associated with axSpA diagnosis. In both cohorts a PFH of ReA, IBD, or psoriasis was not positively associated with HLA-B27 positivity, sacroiliitis on imaging, axSpA diagnosis, or meeting the ASAS criteria for axSpA.ConclusionsIn our cohorts, a PFH of AS or AAU is useful for case-finding of axSpA as this is correlated with HLA-B27 carriership. However, as a PFH of ReA, IBD, or psoriasis does not contribute to identifying axSpA in CBP patients, these data suggest that the widely used ASAS definition of a PFH of SpA should be updated.Trial registrationTrial registration number, NCT01648907. Registered on 20 July 2012.

The yield of a positive MRI of the spine as imaging criterion in the ASAS classification criteria for axial spondyloarthritis: results from the SPACE and DESIR cohorts

Objectives To assess the prevalence of spinal inflammation on MRI in patients with chronic back pain (CBP) of maximally 3 years duration and to evaluate the yield of adding a positive MRI-spine as imaging criterion to the Assessment of SpondyloArthritis international Society (ASAS) classification criteria for axial spondyloarthritis (axSpA). Methods Baseline imaging of the sacroiliac joints (X-SI), MRI of the sacroiliac joints (MRI-SI) and MRI-spine were scored by ≥2 experienced central readers per modality in the SPondyloArthritis Caught Early (SPACE) and DEvenir des Spondylarthropathies Indifférenciées Récentes (DESIR) cohorts. Inflammation suggestive of axSpA was assessed in the entire spine. A positive MRI-spine was defined by the presence of ≥5 inflammatory lesions. Alternative less strict definitions were also tested. Results In this study, 541 and 650 patients with CBP from the SPACE and DESIR cohorts were included. Sacroiliitis on X-SI and MRI-SI was found in 40/541 (7%) and 76/541 (14%) patients in SPACE, and in DESIR in 134/650 (21%) and 231/650 (36%) patients, respectively. In SPACE and DESIR, a positive MRI-spine was seen in 4/541 (1%) and 48/650 (7%) patients. Of the patients without sacroiliitis on imaging, 3/447 (1%) (SPACE) and 8/382 (2%) (DESIR) patients had a positive MRI-spine. Adding positive MRI-spine as imaging criterion led to new classification in only one patient in each cohort, as the other patients already fulfilled the clinical arm. Other definitions of a positive MRI-spine yielded similar results. Conclusion In two cohorts of patients with CBP with a maximum symptom duration of 3 years, a positive MRI-spine was rare in patients without sacroiliitis on MRI-SI and X-SI. Addition of MRI-spine as imaging criterion to the ASAS axSpA criteria had a low yield of newly classified patients and is therefore not recommended.