Poddubnyy, DenisSieper, JoachimAkar, ServetMuñoz Fernández, SantiagoHaibel, HildrunHojnik, MajaGanz, FabianaInman, Robert D.2022-08-042022-08-042022Poddubnyy, D., Sieper, J., Akar, S., Muñoz-Fernández, S., Haibel, H., Hojnik, M., Ganz, F., & Inman, R. D. (2021). Characteristics of Patients With Axial Spondyloarthritis by Geographic Regions: PROOF Multicountry Observational Study Baseline Results. Rheumatology (Oxford, England), 61(8), 3299–3308. https://doi.org/10.1093/rheumatology/keab9011462-03241462-0332http://hdl.handle.net/11268/11561To compare demographic and clinical characteristics of patients with axial spondyloarthritis (axSpA) across geographic regions. Methods: 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 6 geographic regions. Demographics and disease-related parameters were collected. Here we present baseline data for patients who had classification as radiographic (r-)axSpA or non-radiographic (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 significantly higher occurrence of enthesitis (40% vs 33%), psoriasis (10% vs 5%), and inflammatory bowel disease (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 in Canada (9%, 9%, and 2% respectively). Occurrence of uveitis (18%) and psoriasis (14%) was highest in Canada and lowest in China (6% and <1%). IBD was highest in Arabia (21%); no cases were observed in China. In multivariable analysis adjusted for factors potentially affecting peripheral and extra-musculoskeletal manifestations, geographic regions still exhibited significant differences in frequencies of uveitis (p<0.01), psoriasis (p<0.0001) and peripheral arthritis (p<0.0001). Conclusions: The multinational PROOF study of axSpA patients showed significant regional differences in peripheral and extra-musculoskeletal manifestations of SpA, which could be considered in management guidelines and clinical trials.engAttribution-NonCommercial 4.0 International (CC BY-NC 4.0)https://creativecommons.org/licenses/by-nc/4.0/EspondiloartritisReumatologíaSignos y síntomasjournal article10.1093/rheumatology/keab901open accessEnfermedadDemografíaEstudio de caso