Article Text
Abstract
Objectives To investigate the prevalence of axial spondyloarthritis (axSpA) in patients with chronic back pain (CBP) of less than 2 years (2y) duration referred to the rheumatologist, the development of diagnosis over time, and patient characteristics of those developing definite (d-)axSpA over 2y.
Methods We analysed the 2y data from SPondyloArthritis Caught Early, a European cohort of patients (<45 years) with CBP (≥3 months, ≤2y) of unknown origin. The diagnostic workup comprised evaluation of clinical SpA features, acute phase reactants, HLA-B27, radiographs and MRI (sacroiliac joints and spine), with repeated assessments. At each visit (baseline, 3 months, 1y and 2y), rheumatologists reported a diagnosis of axSpA or non-axSpA with level of confidence (LoC; 0-not confident at all to 10-very confident). Main outcome: axSpA diagnosis with LoC≥7 (d-axSpA) at 2y.
Results In 552 patients with CBP, d-axSpA was diagnosed in 175 (32%) at baseline and 165 (30%) at 2y. Baseline diagnosis remained rather stable: at 2y, baseline d-axSpA was revised in 5% of patients, while 8% ‘gained’ d-axSpA. Diagnostic uncertainty persisted in 30%. HLA-B27+ and baseline sacroiliitis imaging discriminated best 2y-d-axSpA versus 2y-d-non-axSpA patients. Good response to non-steroidal anti-inflammatory drugs and MRI-sacroiliitis most frequently developed over follow-up in patients with a new d-axSpA diagnosis. Of the patients who developed MRI-sacroiliitis, 7/8 were HLA-B27+ and 5/8 male.
Conclusion A diagnosis of d-axSpA can be reliably made in nearly one-third of patients with CBP referred to the rheumatologist, but diagnostic uncertainty may persist in 5%–30% after 2y. Repeated assessments yield is modest, but repeating MRI may be worthwhile in male HLA-B27+ patients.
- Spondylitis, Ankylosing
- Outcome and Process Assessment, Health Care
- Classification
Data availability statement
Data are available upon reasonable request.
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Data availability statement
Data are available upon reasonable request.
Footnotes
Handling editor Josef S Smolen
X @sofiaramiro82
DvdH and FAvG contributed equally.
Correction notice This article has been corrected since it published Online First. The author equal contributor statement has been added.
Contributors Study conception and design: DvdH. Acquisition of data: MvL, RAS, RBML, MvdS, KMF, IJB, MvO, SE, RR, FAvG. Dataset management: MLM, MvL, RAS. Analysis and interpretation of data: MLM, FAvG, DvdH, SR. Drafting the manuscript: MLM. All authors critically reviewed the manuscript for important intellectual contribution and approved the final version. Guarantors: MLM and FvG.
Funding MLM is supported by the Fundação para a Ciência e Tecnologia (FCT) grant SFRH/BD/143744/2019.
Competing interests MLM: none. SR: Research Grants—AbbVie, Galapagos, MSD, Novartis, Pfizer, UCB. Consultancy—AbbVie, Eli Lilly, Janssen, MSD, Novartis, Pfizer, Sanofi, UCB. MvL: none. RS: none. RBML: Consultancy—AbbVie, Eli-Lilly, Janssen, Galapagos, Gilead, Novartis, Pfizer, UCB. Director of Rheumatology Consultancy BVD. MvdS: Speaker—Janssen, Novartis, UCB. Consultancy—Abbvie, Eli Lilly, Novartis, UCB. Research Grants:Janssen, Novartis, UCB. KMF: none. IJB: none. MvO: none. SE: Consultancy—AbbVie, Janssen, Novartis, and UCB. RR: Consultancy: Abbvie, Eli-Lilly, Janssen, Novartis, Pfizer, UCB, Amgen. DvdH: Consultancy—AbbVie, ArgenX, Bayer, BMS, Cyxone, Eisai, Galapagos, Gilead, Glaxo-Smith-Kline, Janssen, Lilly, Novartis, Pfizer, Takeda, UCB Pharma. Director of Imaging Rheumatology bv. FAvG: Research Grants -Novartis. Consultancy—MSD, AbbVie, Novartis and BMS.
Patient and public involvement Patients and/or the public were not involved in the design, or conduct, or reporting, or dissemination plans of this research.
Provenance and peer review Not commissioned; externally peer reviewed.
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