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Observational Study
. 2022 Aug 3;61(8):3299-3308.
doi: 10.1093/rheumatology/keab901.

Characteristics of patients with axial spondyloarthritis by geographic regions: PROOF multicountry observational study baseline results

Denis Poddubnyy  1   2 , Joachim Sieper  1 , Servet Akar  3 , Santiago Muñoz-Fernández  4 , Hildrun Haibel  1 , Maja Hojnik  5 , Fabiana Ganz  6 , Robert D Inman  7
Affiliations
Observational Study

Characteristics of patients with axial spondyloarthritis by geographic regions: PROOF multicountry observational study baseline results

Denis Poddubnyy et al. Rheumatology (Oxford). .

Abstract

Objectives: To compare demographic and clinical characteristics of patients with axial SpA (axSpA) across geographic regions.

Methods: Patients With Axial Spondyloarthritis: Multicountry Registry of Clinical Characteristics (PROOF) is an observational study that enrolled recently diagnosed (≤1 year) axSpA patients fulfilling the Assessment of SpondyloArthritis international Society classification criteria from rheumatology clinical practices in 29 countries across six geographic regions. Demographics and disease-related parameters were collected. Here we present baseline data for patients who were classified as radiographic axSpA (r-axSpA) or non-radiographic axSpA (nr-axSpA) confirmed by central reading.

Results: Of the 2170 patients enrolled, 1553 were classified based on central evaluation of sacroiliac radiographs [r-axSpA: 1023 (66%); nr-axSpA: 530 (34%)]. Patients with nr-axSpA had a significantly higher occurrence of enthesitis (40% vs 33%), psoriasis (10% vs 5%) and IBD (4% vs 2%) vs r-axSpA patients. Significant differences in axSpA characteristics were observed between geographic regions. The highest occurrence of peripheral arthritis (60%), enthesitis (52%) and dactylitis (12%) was in Latin America, and the lowest was in Canada (9%, 9% and 2%, respectively). The occurrence of uveitis and psoriasis was highest in Canada (18% and 14%, respectively) and lowest in China (6% and <1%, respectively). IBD was highest in Arabia (21%), and no cases were observed in China. In multivariable analysis adjusted for factors potentially affecting peripheral and extramusculoskeletal manifestations, geographic regions still exhibited significant differences in frequencies of uveitis (P < 0.01), psoriasis (P < 0.0001) and peripheral arthritis (P < 0.0001).

Conclusion: The multinational PROOF study of axSpA patients showed significant regional differences in peripheral and extramusculoskeletal manifestations of SpA, which could be considered in management guidelines and clinical trials.

Keywords: axial spondyloarthritis; characteristics; demographics; non-radiographic; radiographic.

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Figures

<sc>Fig.</sc> 1
Fig. 1
Flowchart of patient selection for the analysis
See this image and copyright information in PMC

References

    1. Braun J, Sieper J.. Classification, diagnosis, and referral of patients with axial spondyloarthritis. Rheum Dis Clin North Am 2012;38:477–85. - PubMed
    1. Sieper J, Poddubnyy D.. Axial spondyloarthritis. Lancet 2017;390:73–84. - PubMed
    1. Feldtkeller E, Khan MA, van der Heijde D, van der Linden S, Braun J.. Age at disease onset and diagnosis delay in HLA-B27 negative vs. positive patients with ankylosing spondylitis. Rheumatol Int 2003;23:61–6. - PubMed
    1. Sykes MP, Doll H, Sengupta R, Gaffney K.. Delay to diagnosis in axial spondyloarthritis: are we improving in the UK? Rheumatology (Oxford) 2015;54:2283–4. - PubMed
    1. Redeker I, Callhoff J, Hoffmann F. et al. Determinants of diagnostic delay in axial spondyloarthritis: an analysis based on linked claims and patient-reported survey data. Rheumatology (Oxford) 2019;58:1634–8. - PubMed

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