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Clinical characteristics of importance to outcome in patients with axial spondyloarthritis: protocol for a prospective descriptive and exploratory cohort study


Introduction Spondyloarthritis (SpA) is a heterogeneous spectrum of rheumatic diseases with either predominantly axial inflammatory symptoms of the spine and sacroiliac joints or predominantly peripheral arthritis. The two main entities of axial SpA (axSpA) are ankylosing spondylitis or non-radiographic axSpA (nr-axSpA). Tumour necrosis factor-α inhibitors have revolutionised the treatment of patients with axSpA who failed to respond to non-steroidal anti-inflammatory drugs and physical therapy. Chronic pain is common in patients with SpA and may still persist despite the lack of signs of inflammation. This has led researchers to hypothesise that central pain sensitisation may play a role in the generation of chronic pain in SpA. The painDETECT Questionnaire (PDQ) is a screening tool developed to detect neuropathic pain components. The primary objective is to explore the prognostic value of the PDQ regarding treatment response in patients with axSpA 3 months after initiating a biological agent. Secondary aim is to evaluate the impact of extra-articular manifestations, comorbidities and patient-reported outcomes and elucidate if these factors influence treatment response.

Method and analysis We will include 60 participants (≥18 years of age) diagnosed with axSpA independent of main entity, who initiate or switch treatment of a biologic. Data will be collected at baseline and at endpoint following Danish clinical practice (≥3 months) of treatment with biologics. We will explore whether the PDQ and other phenotypical patient characteristics are prognostically important for response to biological therapy according to established response criteria like 50% improvement in the Bath Ankylosing Spondylitis Disease Activity Index (50%) and Ankylosing Spondylitis Disease Activity Score.

Ethics and dissemination The study is approved by the Region of Southern Denmark’s Ethics committee (S-20160094) and has been designed in cooperation with patient representatives. The study is registered at (NCT02948608, pre-results). Dissemination will occur through publication(s) in international peer-reviewed journal(s).

  • spondyloarthritis
  • pain
  • prognostic factors
  • spinal diseases
  • ankylosing spondylitis

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  • Contributors RAA serves as the principal investigator for this study. RC, LEK, TE, IMJH, BD and LF participated in the design of the study and drafting of the protocol. BSø-C, HCH, CA, TU, AE, JW and XB have all revised the protocol for intellectual content. XB has made expert opinion on outcome measures in the study. CA and TU have provided expert opinions on various aspects on inflammatory bowel disease. RC has provided expert opinion concerning research design and subsequent statistics. JW has provided expert opinion concerning the eye examination and is responsible for the eye examination. BSø-C, HCH, CA, AE and TU will assist with recruitment of patients. IMJH has been the main supervisor for all aspects of the protocol. RAA is taking the responsibility for the integrity of the protocol manuscript and approves the final version for publication.

  • Funding The study is supported by grants from (1) The Faculty of Health Sciences, University of Southern Denmark, (2) Carl Hansen & Son, (3) The Department of Medicine, Odense University Hospital, Svendborg, (4) The Region of Southern Denmark, (5) The Danish Rheumatism Association, (6) Erna Hamiltons fond, (7) The Parker Institute, Bisbjerg and Frederiksberg Hospital is supported by a core grant from the Oak Foundation.

  • Competing interests RAA, LEK, TE, TU, AE, BD, LF and IMJH have nothing to disclose. RC reports non-financial support from Board membership, grants from Consultancy (AbbVie, Amgen, Axellus A/S, Bristol-Myers Squibb, Cambridge Weight Plan, Celgene, Eli Lilly, Hospira, MSD, Norpharma, Novartis, Orkla Health, Pfizer, Roche, Sobi, Takeda), personal fees from Employment (Research Unit for Musculoskeletal Function and Physiotherapy, Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark), non-financial support from Expert testimony, grants from Grants/grants pending (Axellus A/S, AbbVie, Cambridge Weight Plan, Janssen, MSD, Mundipharma, Novartis, and Roche), grants from Payment for lectures including service on speakers bureaus (Abbott, Amgen, Axellus, Bayer HealthCare Pharmaceuticals, Biogen Idec, Bristol-Myers Squibb, Cambridge Weight Plan, Ipsen, Janssen, Laboratoires Expanscience, MSD, Mundipharma, Norpharma, Novartis, Pfizer, Roche, Rottapharm-Madaus, Sobi, and Wyeth), grants from Payment for manuscript preparation (Axellus, Bristol-Myers Squibb, and Cambridge Weight Plan, Aleris-Hamlet (via Norpharma)), non-financial support from Patents (planned, pending or issued), non financial support from Royalties, grants from Payment for development of educational presentations (Bristol-Myers Squibb, MSD, Pfizer), non-financial support from Stock/stock options, grants from Travel/accommodations/meeting expenses unrelated to activities listed (Abbott, AbbVie, Axellus, Bristol-Myers Squibb, Cambridge Weight Plan, Celgene, Laboratoires Expanscience, Norpharma, Novartis, Pfizer, Roche, Rottapharm-Madaus, and Wyeth), non-financial support from Other (err on the side of full disclosure), outside the submitted work; and he is involved in many healthcare initiatives and research that could benefit from wide uptake of this publication (including Cochrane, OMERACT, IDEOM, RADS and the GRADE Working Group). The Parker Institute is supported by a core grant from the Oak Foundation; The Oak Foundation is a group of philanthropic organizations that, since its establishment in 1983, has given grants to not-for-profit organizations around the world. JW reports personal fees from Abbvie (advisory board), personal fees from Santhera (speaker), grants from Bayer (AAO Congres invitation), outside the submitted Work. CA reports personal fees from Boardmembership (Ferring, Takeda), personal fees from Payment for lectures i (Abbott, Ferring, Norgine, MSD, Takeda), grants from Travel/accommodations/meeting expenses unrelated to activities listed (Abvie, Ferring, Eli Lilly, Norgine, Medtronics, Takeda,Tillots) , outside the submitted work. BC reports personal fees from Pfizer, outside the submitted work. HCH reports personal fees from Advisory Board Abbvie Denmark, psoriatic arthritis, spondyloarthritis and uveitis, personal fees from Advisory Board Novartis Denmark, non-financial (support from Travel/accomodation/meeting expenses unrelated to activity listed Abbvie, Pfizer, BMS, MSD), grants from Payment for educational presentations (Novartis Denmark), outside the submitted work.

  • Provenance and peer review Not commissioned; externally peer reviewed.

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