{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,5]],"date-time":"2026-11-05T19:46:24Z","timestamp":1793907984666,"version":"4.8.0"},"reference-count":18,"publisher":"BMJ","issue":"3","license":[{"start":{"date-parts":[[2021,11,7]],"date-time":"2021-11-07T00:00:00Z","timestamp":1636243200000},"content-version":"unspecified","delay-in-days":6,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"DOI":"10.13039\/100006483","name":"AbbVie","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100006483","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100004336","name":"Novartis","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100004336","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100008897","name":"Janssen Pharmaceuticals","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100008897","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100004334","name":"Merck","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100004334","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100011110","name":"UCB","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100011110","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100004312","name":"Eli Lilly and Company","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100004312","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100004319","name":"Pfizer","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100004319","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["RMD Open"],"accepted":{"date-parts":[[2021,10,5]]},"published-print":{"date-parts":[[2021,11]]},"abstract":"<jats:sec>\n                  <jats:title>Objective<\/jats:title>\n                  <jats:p>To identify clusters of peripheral involvement according to the specific location of peripheral manifestations (ie, arthritis, enthesitis and dactylitis) in patients with spondyloarthritis (SpA) including psoriatic arthritis (PsA), and to evaluate whether these clusters correspond with the clinical diagnosis of a rheumatologist.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Methods<\/jats:title>\n                  <jats:p>Cross-sectional study with 24 participating countries. Consecutive patients diagnosed by their rheumatologist as PsA, axial SpA or peripheral SpA were enrolled. Four different cluster analyses were conducted: one using information on the specific location from all the peripheral manifestations, and a cluster analysis for each peripheral manifestation, separately. Multiple correspondence analyses and k-means clustering methods were used. Distribution of peripheral manifestations and clinical characteristics were compared across the different clusters.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>The different cluster analyses performed in the 4465 patients clearly distinguished a predominantly axial phenotype (cluster 1) and a predominantly peripheral phenotype (cluster 2). In the predominantly axial phenotype, hip involvement and lower limb large joint arthritis, heel enthesitis and lack of dactylitis were more prevalent. In the predominantly peripheral phenotype, different subgroups were distinguished based on the type and location of peripheral involvement: a predominantly involvement of upper versus lower limbs joints, a predominantly axial enthesitis versus peripheral enthesitis, and predominantly finger versus toe involvement in dactylitis. A poor agreement between the clusters and the rheumatologist\u2018s diagnosis as well as with the classification criteria was found.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Conclusion<\/jats:title>\n                  <jats:p>These results suggest the presence of two main phenotypes (predominantly axial and predominantly peripheral) based on the presence and location of the peripheral manifestations.<\/jats:p>\n               <\/jats:sec>","DOI":"10.1136\/rmdopen-2021-001728","type":"journal-article","created":{"date-parts":[[2021,11,8]],"date-time":"2021-11-08T11:50:45Z","timestamp":1636372245000},"page":"e001728","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":17,"title":["Identification of clinical phenotypes of peripheral involvement in patients with spondyloarthritis, including psoriatic arthritis: a cluster analysis in the worldwide ASAS-PerSpA study"],"prefix":"10.1136","volume":"7","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2309-5837","authenticated-orcid":false,"given":"Clementina","family":"L\u00f3pez-Medina","sequence":"first","affiliation":[{"name":"Rheumatology, Cochin Hospital, Assistance Publique H\u00f4pitaux de Paris, Paris, France"},{"name":"Rheumatology, Reina Sofia University Hospital, Maim\u00f3nides Institute for Biomedical Research of C\u00f3rdoba (IMIBIC), University of Cordoba, Cordoba, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sylvie","family":"Chevret","sequence":"additional","affiliation":[{"name":"CRESS, Universit\u00e9 de Paris, INSERM U-1153, Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2246-1986","authenticated-orcid":false,"given":"Anna","family":"Molto","sequence":"additional","affiliation":[{"name":"Rheumatology, Cochin Hospital, Assistance Publique H\u00f4pitaux de Paris, Paris, France"},{"name":"CRESS, Universit\u00e9 de Paris, INSERM U-1153, Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0285-9890","authenticated-orcid":false,"given":"Joachim","family":"Sieper","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology, Infectious Diseases and Rheumatology, Charit\u00e9 Universitatsmedizin Berlin, Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tuncay","family":"Duru\u00f6z","sequence":"additional","affiliation":[{"name":"PMR Department, Rheumatology Division, Marmara University School of Medicine, Istanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5668-4497","authenticated-orcid":false,"given":"Uta","family":"Kiltz","sequence":"additional","affiliation":[{"name":"Rheumatology, Rheumazentrum Ruhrgebiet, Herne, Germany"},{"name":"Rheumatology, Ruhr University Bochum, Bochum, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bassel","family":"Elzorkany","sequence":"additional","affiliation":[{"name":"Rheumatology Department, Cairo University, Cairo, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0722-6822","authenticated-orcid":false,"given":"Najia","family":"Hajjaj-Hassouni","sequence":"additional","affiliation":[{"name":"Health Sciences College, International University of Rabat (UIR), Rabat, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ruben","family":"Burgos-Vargas","sequence":"additional","affiliation":[{"name":"Rheumatology, Hospital General de M\u00e9xico Eduardo Liceaga, Mexico City, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jos\u00e9","family":"Maldonado-Cocco","sequence":"additional","affiliation":[{"name":"Rheumatology, Buenos Aires University School of Medicine, Buenos Aires, Argentina"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4479-7678","authenticated-orcid":false,"given":"Nelly","family":"Ziade","sequence":"additional","affiliation":[{"name":"Rheumatology, Saint Joseph University, Beirut, Lebanon"},{"name":"Rheumatology, Mount Lebanon Hospital, Beirut, Lebanon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Meghna","family":"Gavali","sequence":"additional","affiliation":[{"name":"Department of Rheumatology, Nizam's Institute of Medical Sciences, Hyderabad, Telangana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Victoria","family":"Navarro-Compan","sequence":"additional","affiliation":[{"name":"Rheumatology, University Hospital La Paz, IdiPaz, Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shue-Fen","family":"Luo","sequence":"additional","affiliation":[{"name":"Department of Rheumatology, Allergy and Immunology, Chang Gung Memorial Hospital-Linkou, Taoyuan, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessandro","family":"Biglia","sequence":"additional","affiliation":[{"name":"Rheumatology, Fondazione IRCCS Policlinico S. Matteo, University of Pavia, Pavia, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kim","family":"Tae-Jong","sequence":"additional","affiliation":[{"name":"Department of Rheumatology, Chonnam National University Medical School and Hospital, Gwangju, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4007-1589","authenticated-orcid":false,"given":"Mitsumasa","family":"Kishimoto","sequence":"additional","affiliation":[{"name":"Department of Nephrology and Rheumatology, Kyorin University, Tokyo, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fernando M","family":"Pimentel-Santos","sequence":"additional","affiliation":[{"name":"NOVA Medical School, Universidade Nova Lisboa, Lisboa, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jieruo","family":"Gu","sequence":"additional","affiliation":[{"name":"Rheumatology, The Third Affiliated Hospital of Sun Yat-Sen 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Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marina","family":"Magrey","sequence":"additional","affiliation":[{"name":"MetroHealth Medical Center, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sebasti\u00e1n E","family":"Ib\u00e1\u00f1ez-Vodnizza","sequence":"additional","affiliation":[{"name":"Facultad de Medicina, Clinica Alemana - Universidad del Desarrollo, Santiago, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0684-9542","authenticated-orcid":false,"given":"Wilson","family":"Bautista-Molano","sequence":"additional","affiliation":[{"name":"Rheumatology, University Hospital Fundaci\u00f3n Santa F\u00e9 de Bogot\u00e1 and Universidad El Bosque, Bogot\u00e1, Colombia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1291-1755","authenticated-orcid":false,"given":"Walter","family":"Maksymowych","sequence":"additional","affiliation":[{"name":"Medicine, University of Alberta, Edmonton, Alberta, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8411-7972","authenticated-orcid":false,"given":"Pedro M","family":"Machado","sequence":"additional","affiliation":[{"name":"Centre for Rheumatology and Department of Neuromuscular Diseases, University College London, London, UK"},{"name":"Rheumatology, University College London Hospitals NHS Foundation Trust, London, UK"},{"name":"Rheumatology, Northwick Park Hospital, London North West University Healthcare NHS Trust, London, 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