{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,11]],"date-time":"2026-11-11T14:28:17Z","timestamp":1794407297822,"version":"4.9.0"},"reference-count":28,"publisher":"European Respiratory Society (ERS)","issue":"1","license":[{"start":{"date-parts":[[2025,7,31]],"date-time":"2025-07-31T00:00:00Z","timestamp":1753920000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002284","name":"Asthma Australia","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100002284","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100012697","name":"Clifford Craig Foundation","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100012697","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100004330","name":"GlaxoSmithKline","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100004330","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000925","name":"National Health and Medical Research Council","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100000925","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100018798","name":"Helen Macpherson Smith Trust","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100018798","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100012503","name":"Royal Hobart Hospital Research Foundation","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100012503","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["publications.ersnet.org"],"crossmark-restriction":true},"short-container-title":["ERJ Open Res"],"accepted":{"date-parts":[[2025,6,22]]},"published-print":{"date-parts":[[2026,1]]},"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>\n                      Concavity of the maximal expiratory flow\u2013volume curve is widely regarded as an early indicator of obstructive airways disease. However, its discriminatory accuracy for respiratory outcomes has remained poorly defined. We aimed to examine the discriminatory accuracy of concavity of the maximal expiratory flow\u2013volume curve\n                      <jats:italic>versus<\/jats:italic>\n                      post-bronchodilator (BD) forced expiratory volume in 1\u2005s\/forced vital capacity (FEV\n                      <jats:sub>1<\/jats:sub>\n                      \/FVC) as predictors of incidence of COPD and respiratory symptoms.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      Spirometry was performed on a subset of the Tasmanian Longitudinal Health Study cohort at age 45\u2005years, and incidence of COPD and respiratory symptoms were prospectively monitored over the next 8\u2005years (n=852). Central and peripheral concavity were assessed using a published algorithm based on post-BD forced expiratory flow at 50% of the FVC (FEF\n                      <jats:sub>50%<\/jats:sub>\n                      ) and FEF\n                      <jats:sub>75%<\/jats:sub>\n                      , respectively. Optimal thresholds were determined using the unweighted Youden Index for COPD incidence.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Among participants without COPD at age 45\u2005years, central and peripheral concavity were greater in those who developed COPD by age 53\u2005years than in those who did not (mean difference: +20%, 95% CI 12\u201328, and +15%, 95% CI 7\u201323, respectively). Central concavity above the optimal threshold (27%) had a sensitivity of 70% and specificity of 79% for COPD incidence, while peripheral concavity above the optimal threshold (47%) had a sensitivity of 79% and specificity of 50%. Excess central and peripheral concavity were associated with an increased odds of developing wheeze and exertional dyspnoea over the 8-year follow-up. Post-BD FEV\n                      <jats:sub>1<\/jats:sub>\n                      \/FVC was more sensitive and specific for COPD incidence than the concavity indices, but was not associated with incident respiratory symptoms.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>\n                      Concavity indices were more useful for assessing future risk of respiratory symptoms but had lower discriminatory accuracy for COPD incidence compared to post-BD FEV\n                      <jats:sub>1<\/jats:sub>\n                      \/VC.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1183\/23120541.00472-2025","type":"journal-article","created":{"date-parts":[[2025,7,31]],"date-time":"2025-07-31T17:00:29Z","timestamp":1753981229000},"page":"00472-2025","update-policy":"https:\/\/doi.org\/10.1183\/ers-crossmark-policy","source":"Crossref","is-referenced-by-count":8,"title":["Concavity of the maximal expiratory flow\u2013volume curve, and incidence of COPD and respiratory symptoms: a population-based cohort study"],"prefix":"10.1183","volume":"12","author":[{"given":"Daniel J.","family":"Tan","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1575-6850","authenticated-orcid":false,"given":"David P.","family":"Johns","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Caroline J.","family":"Lodge","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dinh S.","family":"Bui","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0176-0314","authenticated-orcid":false,"given":"Don","family":"Vicendese","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Garun S.","family":"Hamilton","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"MeiLan K.","family":"Han","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3271-3788","authenticated-orcid":false,"given":"Alvar","family":"Agusti","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9954-0538","authenticated-orcid":false,"given":"Michael J.","family":"Abramson","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7034-0615","authenticated-orcid":false,"given":"Jennifer L.","family":"Perret","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shyamali C.","family":"Dharmage","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"E. 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