{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T11:04:19Z","timestamp":1784027059000,"version":"3.55.0"},"reference-count":15,"publisher":"BMJ","issue":"9","license":[{"start":{"date-parts":[[2021,9,14]],"date-time":"2021-09-14T00:00:00Z","timestamp":1631577600000},"content-version":"unspecified","delay-in-days":13,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000050","name":"National Heart, Lung, and Blood Institute","doi-asserted-by":"publisher","award":["K01HL122394"],"award-info":[{"award-number":["K01HL122394"]}],"id":[{"id":"10.13039\/100000050","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100006260","name":"ACR Rheumatology Research Foundation","doi-asserted-by":"crossref","award":["Career Development Bridge Funding Award: K Bridge"],"award-info":[{"award-number":["Career Development Bridge Funding Award: K Bridge"]}],"id":[{"id":"10.13039\/100006260","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/100006260","name":"ACR Rheumatology Research Foundation","doi-asserted-by":"crossref","award":["Within Our Reach: Finding a Cure for RA [Number N\/"],"award-info":[{"award-number":["Within Our Reach: Finding a Cure for RA [Number N\/"]}],"id":[{"id":"10.13039\/100006260","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Autoimmunity Prevention Center","award":["U19 AI050864-10"],"award-info":[{"award-number":["U19 AI050864-10"]}]},{"DOI":"10.13039\/100000062","name":"National Institute for Diabetes and Digestive and Kidney Diseases","doi-asserted-by":"crossref","award":["K24DK110427"],"award-info":[{"award-number":["K24DK110427"]}],"id":[{"id":"10.13039\/100000062","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/100000069","name":"National Institute of Arthritis and Musculoskeletal and Skin Diseases","doi-asserted-by":"publisher","award":["R01 AR051394-05"],"award-info":[{"award-number":["R01 AR051394-05"]}],"id":[{"id":"10.13039\/100000069","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100009713","name":"Foundation for Physical Therapy","doi-asserted-by":"publisher","award":["Miami-Marquette Challenge Research Grant"],"award-info":[{"award-number":["Miami-Marquette Challenge Research Grant"]}],"id":[{"id":"10.13039\/100009713","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open"],"accepted":{"date-parts":[[2021,8,9]]},"published-print":{"date-parts":[[2021,9]]},"abstract":"<jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>Physical activity (PA) in preclinical rheumatoid arthritis (RA) is associated with lower RA risk and disease severity. As joint signs and symptoms of inflammatory arthritis serve as a barrier to PA in RA, it is important to consider whether they affect PA in the time prior to RA. Therefore, we investigated whether joint swelling, stiffness or pain were associated with PA in first-degree relatives (FDRs) of patients with RA, a population at higher risk for future RA.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Design<\/jats:title>\n                    <jats:p>Prospective study design.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Setting<\/jats:title>\n                    <jats:p>We recruited FDRs of patients with RA from academic centres, Veterans\u2019 hospitals and rheumatology clinics or through responses to advertising from six sites across the USA.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Participants<\/jats:title>\n                    <jats:p>We evaluated associations of joint stiffness, joint swelling and joint pain with PA time in 268 FDRs with \u22652 visits over an average 1.2 years. Clinicians confirmed joint swelling. Participants self-reported joint stiffness and\/or pain.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Primary outcome measures<\/jats:title>\n                    <jats:p>PA during a typical 24-hour day was quantified via questionnaire, weighted to reflect metabolic expenditure, where 24 hours was the minimum PA time. Linear mixed models evaluated associations between symptoms and change in PA over time, adjusting for age, sex, race, body mass index, smoking and RA-related autoantibodies.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Average weighted PA time was 37\u00b17 hours. In the cross-sectional analysis, PA time was 1.3\u00b10.9\u2009hours higher in FDRs reporting joint pain (p=0.15); and 0.8\u00b11.6\u2009and 0.4\u00b11\u2009hours lower in FDRs with joint swelling (p=0.60) and stiffness (p=0.69), respectively. Longitudinally, adjusting for baseline PA time, baseline symptoms were not significantly associated with changes in PA time. However, on average over time, joint stiffness and pain were associated with lower PA time (p\n                      <jats:sub>interaction<\/jats:sub>\n                      =0.0002, p\n                      <jats:sub>interaction<\/jats:sub>\n                      =0.002), and joint swelling was associated with higher PA time (p\n                      <jats:sub>interaction<\/jats:sub>\n                      &lt;0.0001).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Baseline symptoms did not predict future PA time, but on average over time, joint symptoms influenced PA time.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjopen-2021-050883","type":"journal-article","created":{"date-parts":[[2021,9,14]],"date-time":"2021-09-14T13:06:29Z","timestamp":1631624789000},"page":"e050883","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":5,"title":["Evaluating associations of joint swelling, joint stiffness and joint pain with physical activity in first-degree relatives of patients with rheumatoid arthritis: Studies of the Aetiology of Rheumatoid Arthritis (SERA), a prospective cohort study"],"prefix":"10.1136","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7255-274X","authenticated-orcid":false,"given":"Jan M","family":"Hughes-Austin","sequence":"first","affiliation":[{"name":"Department of Orthopaedic Surgery, University of California, San Diego, La Jolla, California, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joachim H","family":"Ix","sequence":"additional","affiliation":[{"name":"Department of Medicine, Division of Nephrology-Hypertension, University of California, San Diego, La Jolla, California, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Samuel R","family":"Ward","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, University of California, San Diego, La Jolla, California, USA"},{"name":"Department of Radiology, University of California, San Diego, La Jolla, California, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael H","family":"Weisman","sequence":"additional","affiliation":[{"name":"School of Medicine, Division of Rheumatology, Cedars-Sinai Medical Center, Los Angeles, California, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"James R","family":"ODell","sequence":"additional","affiliation":[{"name":"College of Medicine, Division of Rheumatology, University of Nebraska Medical Center, Omaha, Nebraska, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ted R","family":"Mikuls","sequence":"additional","affiliation":[{"name":"College of Medicine, Division of Rheumatology, University of Nebraska Medical Center, Omaha, Nebraska, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9005-1885","authenticated-orcid":false,"given":"Jane H","family":"Buckner","sequence":"additional","affiliation":[{"name":"Translational Research Institute, Benaroya Research Institute at Virginia Mason, Seattle, Washington, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peter K","family":"Gregersen","sequence":"additional","affiliation":[{"name":"Roberts S Boas Center for Genomics and Human Genetics, Feinstein Institute for Medical Research, Manhasset, New York, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Richard M","family":"Keating","sequence":"additional","affiliation":[{"name":"Division of Rheumatology, Scripps Green Hospital, La Jolla, California, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M Kristen","family":"Demoruelle","sequence":"additional","affiliation":[{"name":"School of Medicine, Department of Rheumatology, University of Colorado - Anschutz Medical Campus, Aurora, Colorado, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kevin D","family":"Deane","sequence":"additional","affiliation":[{"name":"School of Medicine, Department of Rheumatology, University of Colorado - Anschutz Medical Campus, Aurora, Colorado, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"V Michael","family":"Holers","sequence":"additional","affiliation":[{"name":"School of Medicine, Department of Rheumatology, University of Colorado - Anschutz Medical Campus, Aurora, Colorado, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jill M","family":"Norris","sequence":"additional","affiliation":[{"name":"Department of Epidemiology, Colorado School of Public Health, University of Colorado - Anschutz Medical Campus, Aurora, Colorado, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2021,9,14]]},"reference":[{"key":"2025101810100958000_11.9.e050883.1","doi-asserted-by":"crossref","first-page":"1121","DOI":"10.1586\/1744666X.2015.1067606","article-title":"The role of exercise in the management of rheumatoid arthritis","volume":"11","author":"Metsios","year":"2015","journal-title":"Expert Rev Clin Immunol"},{"key":"2025101810100958000_11.9.e050883.2","doi-asserted-by":"publisher","DOI":"10.1016\/j.autrev.2017.11.010"},{"key":"2025101810100958000_11.9.e050883.3","doi-asserted-by":"publisher","DOI":"10.1002\/art.23255"},{"key":"2025101810100958000_11.9.e050883.4","doi-asserted-by":"publisher","DOI":"10.1136\/rmdopen-2017-000434"},{"key":"2025101810100958000_11.9.e050883.5","doi-asserted-by":"publisher","DOI":"10.1007\/s40279-015-0363-2"},{"key":"2025101810100958000_11.9.e050883.6","doi-asserted-by":"crossref","DOI":"10.1186\/s13075-015-0560-2","article-title":"Physical activity and risk of rheumatoid arthritis in women: a population-based prospective study","volume":"17","author":"Di Giuseppe","year":"2015","journal-title":"Arthritis Res Ther"},{"key":"2025101810100958000_11.9.e050883.7","doi-asserted-by":"publisher","DOI":"10.1136\/annrheumdis-2014-205180"},{"key":"2025101810100958000_11.9.e050883.8","doi-asserted-by":"publisher","DOI":"10.1136\/annrheumdis-2012-201505"},{"key":"2025101810100958000_11.9.e050883.9","doi-asserted-by":"publisher","DOI":"10.1002\/art.24833"},{"key":"2025101810100958000_11.9.e050883.10","doi-asserted-by":"publisher","DOI":"10.1002\/art.38022"},{"key":"2025101810100958000_11.9.e050883.11","doi-asserted-by":"publisher","DOI":"10.1002\/art.1780310302"},{"key":"2025101810100958000_11.9.e050883.12","doi-asserted-by":"crossref","first-page":"1828","DOI":"10.1002\/art.39630","article-title":"Associations of smoking and age with inflammatory joint signs among unaffected first-degree relatives of rheumatoid arthritis patients: results from studies of the etiology of rheumatoid arthritis","volume":"68","author":"Sparks","year":"2016","journal-title":"Arthritis Rheumatol"},{"key":"2025101810100958000_11.9.e050883.13","doi-asserted-by":"publisher","DOI":"10.1002\/art.27584"},{"key":"2025101810100958000_11.9.e050883.14","doi-asserted-by":"publisher","DOI":"10.1136\/heartjnl-2012-303461"},{"key":"2025101810100958000_11.9.e050883.15","doi-asserted-by":"crossref","first-page":"1069","DOI":"10.1002\/acr.22799","article-title":"Trajectories of physical activity over two years in persons with rheumatoid arthritis","volume":"68","author":"Demmelmaier","year":"2016","journal-title":"Arthritis Care Res"}],"container-title":["BMJ Open"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/bmjopen-2021-050883","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,18]],"date-time":"2025-10-18T17:10:20Z","timestamp":1760807420000},"score":1,"resource":{"primary":{"URL":"https:\/\/bmjopen.bmj.com\/lookup\/doi\/10.1136\/bmjopen-2021-050883"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,9]]},"references-count":15,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2021,9,14]]},"published-print":{"date-parts":[[2021,9]]}},"alternative-id":["10.1136\/bmjopen-2021-050883"],"URL":"https:\/\/doi.org\/10.1136\/bmjopen-2021-050883","relation":{"has-preprint":[{"id-type":"doi","id":"10.1101\/2020.06.13.20130526","asserted-by":"object"}]},"ISSN":["2044-6055","2044-6055"],"issn-type":[{"value":"2044-6055","type":"print"},{"value":"2044-6055","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,9]]}}}