{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,11]],"date-time":"2026-11-11T16:02:18Z","timestamp":1794412938073,"version":"4.9.1"},"reference-count":36,"publisher":"BMJ","issue":"3","license":[{"start":{"date-parts":[[2021,12,8]],"date-time":"2021-12-08T00:00:00Z","timestamp":1638921600000},"content-version":"unspecified","delay-in-days":7,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000265","name":"Medical Research Council","doi-asserted-by":"publisher","award":["MR\/L01629X"],"award-info":[{"award-number":["MR\/L01629X"]}],"id":[{"id":"10.13039\/501100000265","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["RMD Open"],"accepted":{"date-parts":[[2021,11,16]]},"published-print":{"date-parts":[[2021,12]]},"abstract":"<jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>To assess changes in ankylosing spondylitis (AS) incidence, prevalence and time to diagnosis, between 1998 and 2017.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Using UK GP data from the Clinical Practice Research Datalink, we identified patients diagnosed with AS between 1998 and 2017. We estimated the annual AS incidence, prevalence and length of time from first recorded symptom of back pain to rheumatology referral and diagnosis.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>We identified 12\u2009333 patients with AS. The incidence declined from 0.72 (\u00b10.14) per 10\u2009000 patient-years in 1998 to 0.39 (\u00b10.06) in 2007, with this decline significant only in men, then incidence rose to 0.57 (\u00b10.11) in 2017. By contrast, prevalence increased between 1998 and 2017 (from 0.13%\u00b10.006\u2009to 0.18%\u00b10.006), rising steeply among women (from 0.06%\u00b10.05\u2009to 0.10%\u00b10.06) and patients aged \u226560 (from 0.14%\u00b10.01\u2009to 0.26%\u00b10.01). The overall median time from first symptom to rheumatology referral was 4.87 years (IQR=1.42\u201310.23). The median time from first symptom to diagnosis rose between 1998 and 2017 (from 3.62 years (IQR=1.14\u20137.07) to 8.31 (IQR=3.77\u201315.89)) and was longer in women (6.71 (IQR=2.30\u201312.36)) than men (5.65 (IQR=1.66\u201311.20)).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>AS incidence declined significantly between 1998 and 2007, with an increase between 2007 and 2017 that may be explained by an improvement in the recognition of AS or confidence in diagnosing AS over time, stemming from increased awareness of inflammatory back pain and the importance of early treatment. The rising AS prevalence may indicate improved patient survival. The persisting delay in rheumatology referral and diagnosis remains of concern, particularly in women.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/rmdopen-2021-001888","type":"journal-article","created":{"date-parts":[[2021,12,9]],"date-time":"2021-12-09T11:40:51Z","timestamp":1639050051000},"page":"e001888","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":87,"title":["Changes in ankylosing spondylitis incidence, prevalence and time to diagnosis over two decades"],"prefix":"10.1136","volume":"7","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7337-3527","authenticated-orcid":false,"given":"Samantha S R","family":"Crossfield","sequence":"first","affiliation":[{"name":"Leeds Institute for Data Analytics, University of Leeds, Leeds, UK"},{"name":"Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Helena","family":"Marzo-Ortega","sequence":"additional","affiliation":[{"name":"Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds, UK"},{"name":"NIHR Leeds Biomedical Research Centre, Leeds Teaching Hospitals NHS Trust, Leeds, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarah R","family":"Kingsbury","sequence":"additional","affiliation":[{"name":"Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds, UK"},{"name":"NIHR Leeds Biomedical Research Centre, Leeds Teaching Hospitals NHS Trust, Leeds, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mar","family":"Pujades-Rodriguez","sequence":"additional","affiliation":[{"name":"Leeds Institute of Health Sciences, University of Leeds, Leeds, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3478-5665","authenticated-orcid":false,"given":"Philip G","family":"Conaghan","sequence":"additional","affiliation":[{"name":"Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds, UK"},{"name":"NIHR Leeds Biomedical Research Centre, Leeds Teaching Hospitals NHS Trust, Leeds, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2021,12,9]]},"reference":[{"key":"2025090313335984000_7.3.e001888.1","doi-asserted-by":"publisher","DOI":"10.1007\/s00296-002-0237-4"},{"key":"2025090313335984000_7.3.e001888.2","doi-asserted-by":"crossref","first-page":"121","DOI":"10.1007\/s00296-002-0261-4","article-title":"Functional disability and quality of life in patients with ankylosing spondylitis","volume":"23","author":"Bostan","year":"2003","journal-title":"Rheumatol Int"},{"key":"2025090313335984000_7.3.e001888.3","doi-asserted-by":"crossref","first-page":"512","DOI":"10.1016\/j.berh.2015.04.002","article-title":"The impact of ankylosing spondylitis\/axial spondyloarthritis on work productivity","volume":"29","author":"Martindale","year":"2015","journal-title":"Best Pract Res Clin Rheumatol"},{"key":"2025090313335984000_7.3.e001888.4","doi-asserted-by":"publisher","DOI":"10.1038\/s41598-019-40055-1"},{"key":"2025090313335984000_7.3.e001888.5","doi-asserted-by":"crossref","first-page":"1379","DOI":"10.1016\/S0140-6736(07)60635-7","article-title":"Ankylosing spondylitis","volume":"369","author":"Braun","year":"2007","journal-title":"The Lancet"},{"key":"2025090313335984000_7.3.e001888.6","doi-asserted-by":"crossref","unstructured":"McLeod C , Bagust A , Boland A . 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Low back pain: early management of persistent non-specific low back pain. London: National Collaborating Centre for Primary Care, Royal College of General Practitioners, 2009: 9\u201313."},{"key":"2025090313335984000_7.3.e001888.28","unstructured":"National Institute for Health and Care Excellence . Ankylosing spondylitis: how do I make a working diagnosis of ankylosing spondylitis? 2019. 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