{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T09:54:20Z","timestamp":1781517260792,"version":"3.54.1"},"reference-count":32,"publisher":"BMJ","issue":"7","funder":[{"DOI":"10.13039\/100004319","name":"Pfizer","doi-asserted-by":"publisher","award":["no grant number"],"award-info":[{"award-number":["no grant number"]}],"id":[{"id":"10.13039\/100004319","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100004336","name":"Novartis","doi-asserted-by":"publisher","award":["no grant number"],"award-info":[{"award-number":["no grant number"]}],"id":[{"id":"10.13039\/100004336","id-type":"DOI","asserted-by":"publisher"}]},{"name":"NIH","award":["75N92023D00011"],"award-info":[{"award-number":["75N92023D00011"]}]},{"name":"NIH","award":["NCT00608764"],"award-info":[{"award-number":["NCT00608764"]}]},{"DOI":"10.13039\/100004330","name":"GlaxoSmithKline","doi-asserted-by":"publisher","award":["no grant number"],"award-info":[{"award-number":["no grant number"]}],"id":[{"id":"10.13039\/100004330","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100009655","name":"Sunovion","doi-asserted-by":"publisher","award":["no grant number"],"award-info":[{"award-number":["no grant number"]}],"id":[{"id":"10.13039\/100009655","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100008184","name":"COPD Foundation","doi-asserted-by":"publisher","award":["no grant number"],"award-info":[{"award-number":["no grant number"]}],"id":[{"id":"10.13039\/100008184","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100004328","name":"Genentech","doi-asserted-by":"publisher","award":["no grant number"],"award-info":[{"award-number":["no grant number"]}],"id":[{"id":"10.13039\/100004328","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000050","name":"NHLBI","doi-asserted-by":"crossref","award":["U01HL089856"],"award-info":[{"award-number":["U01HL089856"]}],"id":[{"id":"10.13039\/100000050","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/100000050","name":"NHLBI","doi-asserted-by":"crossref","award":["U01HL089897"],"award-info":[{"award-number":["U01HL089897"]}],"id":[{"id":"10.13039\/100000050","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["Thorax"],"accepted":{"date-parts":[[2026,3,14]]},"published-print":{"date-parts":[[2026,7]]},"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Change in 6-min walk distance (6MWD) over time serves as a measure of change in functional exercise performance. We analysed a large cohort of current or former tobacco smokers over a 5-year period to identify correlates of 6MWD decline.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>A total of 4734 participants with normal spirometry or spirometric evidence of chronic obstructive pulmonary disease (COPD) who completed a 5-year follow-up in the COPDGene study were included. Baseline and 5-year assessments included 6MWD, spirometry, St. George\u2019s Respiratory Questionnaire (SGRQ), gender, race and CT measures of emphysema, gas trapping and airway wall thickness. 6MWD decline correlates relative to baseline and 5-year changes were examined using univariate and multivariate linear regression.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      At baseline, 2573 had normal spirometry; 487 were classified as GOLD1, 1044 as GOLD2, 514 as GOLD3 and 116 as GOLD4. Average 5-year decline in 6MWD was 35.6\u00b1101.7 (SD) metres (p&lt;0.001). COPD participants experienced greater 6MWD decline (44.1\u00b1101.9\u2009m, p&lt;0.001) compared with those with normal spirometry (28.5\u00b1101.0\u2009m, p&lt;0.001). Only baseline 6MWD and study site accounted for appreciable fractions of 6MWD decline variance (R\n                      <jats:sup>2<\/jats:sup>\n                      =12.1%\u2009and 9.1%, respectively). 5\u2009year change in variables assessed (including FEV\n                      <jats:sub>1<\/jats:sub>\n                      and SGRQ) explained only small fractions of 6MWD decline variance (each R\n                      <jats:sup>2<\/jats:sup>\n                      \u22645%).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>6MWD declined significantly, but with high variability; spirometry, CT, health status, demographic and anthropometric measures accounted for only small portions of this variance. Our findings suggest that a meaningful decline in 6MWD observed over 5 years in COPD patients is in large part related to factors other than decline in pulmonary structure or function.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/thorax-2025-224183","type":"journal-article","created":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T17:20:36Z","timestamp":1776187236000},"page":"664-671","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":1,"title":["Correlates of 5-year decline in 6-min walk distance in the COPDGene cohort"],"prefix":"10.1136","volume":"81","clinical-trial-number":[{"clinical-trial-number":"nct00608764","registry":"10.18810\/clinical-trials-gov"}],"author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1467-5629","authenticated-orcid":false,"given":"Aladin M","family":"Boriek","sequence":"first","affiliation":[{"name":"Department of Medicine, Section of Pulmonary, Critical Care, and Sleep Medicine, Baylor College of Medicine, Houston, Texas, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joseph","family":"Gordon","sequence":"additional","affiliation":[{"name":"Respiratory Research Center, Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, USA"},{"name":"Division of Respiratory and Critical Care Physiology and Medicine, Harbor-UCLA Medical Center, Torrance, California, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yeongjin","family":"Gwon","sequence":"additional","affiliation":[{"name":"Department of Biostatistics, College of Public Health, University of Nebraska Medical Center, Omaha, Nebraska, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1917-9296","authenticated-orcid":false,"given":"Alessandra","family":"Adami","sequence":"additional","affiliation":[{"name":"Respiratory Research Center, Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, USA"},{"name":"Department of Kinesiology, College of Health Sciences, University of Rhode Island, Kingston, Rhode Island, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Janos","family":"Porszasz","sequence":"additional","affiliation":[{"name":"Respiratory Research Center, Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, USA"},{"name":"Division of Respiratory and Critical Care Physiology and Medicine, Harbor-UCLA Medical Center, Torrance, California, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7884-0726","authenticated-orcid":false,"given":"Harry B","family":"Rossiter","sequence":"additional","affiliation":[{"name":"Respiratory Research Center, Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, California, USA"},{"name":"Division of Respiratory and Critical Care Physiology and Medicine, Harbor-UCLA Medical Center, Torrance, California, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mehdi","family":"Rambod","sequence":"additional","affiliation":[{"name":"Internal medicine, Interventional cardiology, WellMed Medical Management, San Antonio, San Antonio, Texas, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Divay","family":"Chandra","sequence":"additional","affiliation":[{"name":"Department of Medicine, Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5037-2919","authenticated-orcid":false,"given":"Alejandro A","family":"Diaz","sequence":"additional","affiliation":[{"name":"Division of Pulmonary and Critical Care Medicine, Brigham and Women\u2019s Hospital, Harvard Medical School, Brigham and Women\u2019s Hospital, Boston, Massachusetts, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Greg L","family":"Kinney","sequence":"additional","affiliation":[{"name":"Department of Epidemiology, Colorado School of Public Health, University of Colorado Denver, Aurora, Colorado, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Barry J","family":"Make","sequence":"additional","affiliation":[{"name":"Department of Medicine, National Jewish Health, Denver, Colorado, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2647-9422","authenticated-orcid":false,"given":"Merry-Lynn N","family":"McDonald","sequence":"additional","affiliation":[{"name":"Department of Medicine, Division of Pulmonary, Allergy, and Critical Care Medicine, University of Alabama at Birmingham Health System, Birmingham, Alabama, 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