Session Type: Abstract Submissions (ACR)
Background/Purpose: According to the ASAS axial spondyloarthritis (SpA) criteria, patients suffering from inflammatory back pain (IBP) can be recognized as suffering from axial SpA even in the absence of structural damage of the sacroiliac joints (SIJ) but the natural history of these patients is not well known.The objective of this study was to evaluate 1) the rate of SIJ structural progression over a 2 years period and 2) the influence of baseline objective signs of inflammation on this progression rate in patients suffering from recent onset inflammatory back pain suggestive of SpA.
Methods: Patients: IBP < 3 years duration suggestive of axial SpA according to the treating rheumatologist (DESIR cohort) Outcome measures: Pelvic X-rays collected both at baseline and at the 2 year follow up visit and MRI of the SIJ collected at baseline were stored after anonymizing and blinding for the visit. Radiographic structural damage was defined as the fulfillment of the modified New-York (mNY) criteria and inflammation on MRI (“positive MRI”) was defined according to the ASAS criteria. The radiographs and MRIs were read centrally by two pairs of well calibrated central readers blinded for clinical, laboratory and other imaging data. In case of disagreement, images were adjudicated by an experienced radiologist. CRP at baseline was defined as abnormal if >6mg/l.
Results: Of the 708 enrolled patients, 449 had a complete radiological data set (34 + 9 years old, 53 % females, HLA B27 positive: 61%). At baseline, 123 of 449 (27%) fulfilled the mNY criteria. Of the remaining 326 patients, 16 (4.9%) progressed (fulfilling the mNY criteria at the 2 year visit). Among these 326 patients, baseline MRI, CRP and both MRI and CRP were available in 307, 314 and 303 patients respectively. The table summarizes the main findings of this study. MRI positivity, CRP abnormality and either MRI positivity or CRP abnormality was observed in 14/15 (93%) versus 67/292 (23%), 7/15 (46%) versus 61/299 (20%) and 14/15 (93%) versus 111/288 (39%) of the patients with versus without a radiographic progression after the 2 year follow-up visit. A normal MRI and CRP at baseline almost excluded the development of sacroiliitis according to the mNY criteria after two years
Table : SIJ structural progression among the 326 patients not fulfilling SIJ mNY criteria at baseline
|SIJ structural progression|
|Baseline Variable||mNY Positive at year 2||mNY Negative at year 2|
*values given are the number of patients and OR : Odds ratio [95% confidence interval]; PPV: positive predictive value; NPV: negative predictive value**baseline inflammation : either MRI positive or abnormal CRP
Conclusion: These data suggest that 1) SIJ structural progression to fulfillment of mNY criteria in this cohort was low after a two years follow-up period 2) the presence of objective signs of inflammation are a predisposing factor of structural progression keeping in mind that the majority of patients with baseline signs of inflammation did not progress.
R. van den Berg,
V. Vo Hoang,
D. van der Heijde,
« Back to 2014 ACR/ARHP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/two-years-sacroiliac-radiographic-progression-rate-and-influence-of-baseline-markers-of-inflammation-in-recent-onset-spondyloarthritis/