From GOLD 0 to Pre-COPD

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usa-input-error-message selection-validation-message"> Name must be less than 100 characters </div> </div> <div class="action-panel-control-wrap existing-collections-controls"> <label for="collections-action-panel-add-to-existing" class="action-panel-label"> Choose a collection: </label> <select id="collections-action-panel-add-to-existing" class="action-panel-selector collections-action-add-to-existing" data-ga-category="save_share" data-ga-action="select_collection" data-ga-label="($('#collections-action-add-to-existing').val() === 'Favorites') ? 'Favorites' : 'non_favorites_collection'"> </select> <div class="collections-retry-load-on-error usa-input-error-message selection-validation-message"> Unable to load your collection due to an error<br> <a href="#">Please try again</a> </div> </div> </div> <div class="action-panel-actions"> <button class="action-panel-submit" type="submit" data-loading-label="Adding..." data-pinger-ignore data-ga-category="save_share" data-ga-action="collections" data-ga-label="add"> Add </button> <button class="action-panel-cancel" aria-label="Close 'Add to Collections' panel" ref="linksrc=close_collections_panel" aria-controls="collections-action-panel" aria-expanded="false" data-ga-category="save_share" data-ga-action="collections" data-ga-label="cancel"> Cancel </button> </div> </form> </div> </div> <div id="bibliography-action-panel" class="bibliography-action-panel action-panel in-progress-dots-panel" aria-hidden="true" data-bibliography-open-panel-enabled="false" data-bibliography-open-panel-url-hash="#open-bibliography-panel"> <div class="inner-wrap"> <h3 class="action-panel-heading"> Add to My Bibliography </h3> <form id="bibliography-action-panel-form" class="bibliography-action-panel-form action-panel-content action-form action-panel-smaller-selectors" data-add-to-bibliography-max-amount="100" data-add-to-bibliography-batch-size="10" data-bibliography-delegates-url="/list-bibliography-delegates/" data-add-to-bibliography-url="/add-to-bibliography/" data-get-article-ids-by-search-url="/get-article-ids-by-search/" data-mybib-root-url="https://www.ncbi.nlm.nih.gov/myncbi/collections/mybibliography/"> <input type="hidden" name="csrfmiddlewaretoken" value="XgwDGgX3l8VeKas0VZtfIInguJGIrMiPrwpXYddnRFit8Lt6ZxoXEOKZ5Ihi2KfD"> <div class="action-panel-control-wrap bibliographies-controls"> <div class="choice-group"> <ul class="bibliographies-action-add radio-group-items"> <li> <input name="bibliography" id="my-bibliography" class="my-bibliography" type="radio" checked/> <label for="my-bibliography">My Bibliography</label> </li> </ul> </div> </div> <div class="bibliographies-retry-load-on-error usa-input-error-message selection-validation-message"> Unable to load your delegates due to an error<br> <a href="#">Please try again</a> </div> <div class="action-panel-actions"> <button class="action-panel-submit" type="submit" data-loading-label="Adding..." data-pinger-ignore> Add </button> <button class="action-panel-cancel" aria-label="Close 'Add to bibliography' panel" ref="linksrc=close_bibliography_panel" aria-controls="bibliography-action-panel" aria-expanded="false" data-ga-category="save_share" data-ga-action="mybib" data-ga-label="cancel"> Cancel </button> </div> </form> </div> </div> <div id="saved-search-action-panel" class="saved-search-action-panel action-panel " aria-hidden="true" data-saved-search-open-panel-enabled="false" data-saved-search-open-panel-url-hash="#open-saved-search-panel"> <div class="inner-wrap"> <h2 class="action-panel-heading"> Your saved search </h2> <form id="saved-search-action-panel-form" class="saved-search-action-panel-form action-panel-content action-form" data-create-saved-search-url="/create-saved-search/" data-try-search-terms-url="/try-search-term/" data-saved-search-root-url="https://www.ncbi.nlm.nih.gov/myncbi/searches/"> <input type="hidden" name="csrfmiddlewaretoken" value="XgwDGgX3l8VeKas0VZtfIInguJGIrMiPrwpXYddnRFit8Lt6ZxoXEOKZ5Ihi2KfD"> <div class="action-panel-control-wrap"> <label for="saved-search-name" class="action-panel-label saved-search-name-label required-field-asterisk"> Name of saved search: </label> <input maxlength="200" type="text" name="saved-search-name" id="saved-search-name" class="saved-search-name" value="" required pattern="[^"&=<>\/]*" title="The following characters are not allowed in the Name field: "&=<>/"> </div> <div class="action-panel-control-wrap"> <label for="saved-search-term" class="action-panel-label required-field-asterisk"> Search terms: </label> <textarea name="saved-search-term" id="saved-search-term" class="saved-search-term" required></textarea> </div> <div class="test-search-term-wrap"> <a href="#" class="try-search-term">Test search terms</a> </div> <div class="choice-group action-panel-extra-margin-top"> <span class="action-panel-label" id="fieldset-label"> Would you like email updates of new search results? </span> <fieldset id="saved-search-alert" aria-describedby="fieldset-label"> <legend class="usa-sr-only">Saved Search Alert Radio Buttons</legend> <ul class="radio-group-items"> <li> <input type="radio" id="saved-search-alert-yes" class="saved-search-alert-yes" name="saved-search-alert" value="yes" checked> <label for="saved-search-alert-yes" class="action-panel-label">Yes</label> </li> <li> <input aria-label="No radio input" type="radio" id="saved-search-alert-no" class="saved-search-alert-no" name="saved-search-alert" value="no"> <label for="saved-search-alert-no" class="action-panel-label">No</label> </li> </ul> </fieldset> </div> <div class="alert-schedule-wrap"> <div class="action-panel-control-wrap"> <label class="action-panel-label"> Email: </label> <span aria-label="Email address" id="saved-search-email" class="action-panel-label"><span class="action-panel-label-bold"></span> (<a class="myncbi-account-settings" href="https://www.ncbi.nlm.nih.gov/account/settings/">change</a>)</span> </div> <div class="action-panel-control-wrap action-panel-extra-margin-top"> <label for="saved-search-frequency" class="action-panel-label"> Frequency: </label> <select id="saved-search-frequency" class="no-border-panel-selector saved-search-frequency"> <option value="monthly">Monthly</option> <option value="weekly">Weekly</option> <option value="daily">Daily</option> </select> </div> <div class="action-panel-control-wrap saved-search-monthly-additional"> <label for="saved-search-monthly-on-day" class="action-panel-label"> Which day? </label> <select id="saved-search-monthly-on-day" class="no-border-panel-selector"> <option value="Sunday">The first Sunday</option> <option value="Monday">The first Monday</option> <option value="Tuesday">The first Tuesday</option> <option value="Wednesday">The first Wednesday</option> <option value="Thursday">The first Thursday</option> <option value="Friday">The first Friday</option> <option value="Saturday">The first Saturday</option> <option value="day">The first day</option> <option value="weekday">The first weekday</option> </select> </div> <div class="action-panel-control-wrap saved-search-weekly-additional"> <label for="saved-search-weekly-on-day" class="action-panel-label"> Which day? </label> <select id="saved-search-weekly-on-day" class="no-border-panel-selector saved-search-weekly-on-day"> <option value="Sunday">Sunday</option> <option value="Monday">Monday</option> <option value="Tuesday">Tuesday</option> <option value="Wednesday">Wednesday</option> <option value="Thursday">Thursday</option> <option value="Friday">Friday</option> <option value="Saturday">Saturday</option> </select> </div> <div class="action-panel-control-wrap"> <label for="saved-search-report" class="action-panel-label"> Report format: </label> <select id="saved-search-report" class="no-border-panel-selector saved-search-report"> <option value="DocSum">Summary</option> <option value="DocSumText">Summary (text)</option> <option value="Abstract">Abstract</option> <option value="AbstractText">Abstract (text)</option> <option value="MEDLINE">PubMed</option> </select> </div> <div class="action-panel-control-wrap"> <label for="saved-search-amount" class="action-panel-label"> Send at most: </label> <select id="saved-search-amount" class="no-border-panel-selector saved-search-amount"> <option value="1">1 item</option> <option value="5" selected>5 items</option> <option value="10">10 items</option> <option value="20">20 items</option> <option value="50">50 items</option> <option value="100">100 items</option> <option value="200">200 items</option> </select> </div> <div> <input type="checkbox" id="saved-search-send-if-no-result" class="saved-search-send-if-no-result" name="saved-search-send-if-no-result"> <label for="saved-search-send-if-no-result" class="action-panel-label smaller-checkbox"> Send even when there aren't any new results </label> </div> <div class="action-panel-control-wrap option-text-in-email-wrap"> <label for="saved-search-email-text" class="action-panel-label"> Optional text in email: </label> <textarea name="saved-search-email-text" id="saved-search-email-text" class="saved-search-email-text"></textarea> </div> </div> <div class="action-panel-actions"> <button class="action-panel-submit" type="submit" data-loading-label="Saving..." data-ga-category="save_share" data-ga-action="alert" data-ga-label="save"> Save </button> <button class="action-panel-cancel" aria-label="Close 'Your saved search' panel" ref="linksrc=close_saved_search_panel" aria-controls="saved-search-action-panel" aria-expanded="false" data-ga-category="save_share" data-ga-action="alert" data-ga-label="cancel"> Cancel </button> </div> </form> </div> </div> <div id="citation-manager-action-panel" class="citation-manager-action-panel action-panel" aria-hidden="true"> <div class="inner-wrap"> <h2 class="action-panel-heading"> Create a file for external citation management software </h2> <form id="citation-manager-action-panel-form" class="action-panel-content action-form" action="/results-export-ids/" data-by-search-action="/results-export-search-data/" data-by-ids-action="/results-export-ids/" method="post" data-by-search-method="post" data-by-ids-method="post"> <input type="hidden" name="csrfmiddlewaretoken" value="XgwDGgX3l8VeKas0VZtfIInguJGIrMiPrwpXYddnRFit8Lt6ZxoXEOKZ5Ihi2KfD"> <input name="results-format" type="hidden" value="pubmed"/> <div class="action-panel-actions"> <button class="action-panel-submit" type="submit" data-loading-label="Sending..." data-ga-category="save_share" data-ga-action="citation_manager" data-ga-label="save"> Create file </button> <button class="action-panel-cancel" aria-label="Close 'Send citations to citation manager' panel" ref="linksrc=close_citation_manager_panel" aria-controls="citation-manager-action-panel" aria-expanded="false" data-ga-category="save_share" data-ga-action="citation_manager" data-ga-label="cancel"> Cancel </button> </div> </form> </div> </div> <div id="rss-action-panel" class="rss-action-panel action-panel " aria-hidden="true"> <div class="inner-wrap"> <h2 class="action-panel-heading"> Your RSS Feed </h2> <form id="rss-action-panel-form" class="rss-action-panel-form action-panel-content action-form" data-create-rss-feed-url="/create-rss-feed-url/" data-search-form-term-value=""> <input type="hidden" name="csrfmiddlewaretoken" value="XgwDGgX3l8VeKas0VZtfIInguJGIrMiPrwpXYddnRFit8Lt6ZxoXEOKZ5Ihi2KfD"> <div class="action-panel-control-wrap"> <label for="rss-name" class="action-panel-label required-field-asterisk"> Name of RSS Feed: </label> <input maxlength="200" placeholder="Name" type="text" name="rss-name" id="rss-name" class="rss-name" value='' required pattern="[^"&=<>\/]*" title="The following characters are not allowed in the Name field: "&=<>/"> </div> <div class="rss-limit-wrap"> <div class="action-panel-control-wrap action-panel-extra-margin-top"> <label for="rss-limit" class="action-panel-label"> Number of items displayed: </label> <select id="rss-limit" class="no-border-panel-selector rss-limit"> <option value="5">5</option> <option value="10">10</option> <option value="15" selected="selected">15</option> <option value="20">20</option> <option value="50">50</option> <option value="100">100</option> </select> </div> </div> <div class="action-panel-actions"> <button class="action-panel-submit" type="submit" data-loading-label="Creating..." data-ga-category="save_share" data-ga-action="alert" data-ga-label="save"> Create RSS </button> <button class="action-panel-cancel" aria-label="Close 'Your RSS' panel" ref="linksrc=close_rss_panel" aria-controls="rss-action-panel" aria-expanded="false" data-ga-category="save_share" data-ga-action="alert" data-ga-label="cancel"> Cancel </button> </div> <div class="action-panel-control-wrap rss-link-copy-wrap"> <label for="rss-link" class="usa-sr-only">RSS Link</label> <input placeholder="Your RSS Feed Link" type="text" name="rss-link" id="rss-link" class="rss-link" title="RSS Link"> <button type="button" disabled class="rss-link-copy-button disabled" data-ga-category="save_share" data-ga-action="rss" data-ga-label="copy"> Copy </button> </div> </form> </div> </div> </div> </div> <div class="article-page" id="article-page" data-article-pmid="33211970"> <aside class="page-sidebar"> <div class="inner-wrap"> <div class="full-text-links"> <div class="full-view"> <h3 class="title"> Full text links </h3> <div class="full-text-links-list"> <a class="link-item dialog-focus" 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data-collections-root-url="https://www.ncbi.nlm.nih.gov/myncbi/collections/"><input type="hidden" name="csrfmiddlewaretoken" value="XgwDGgX3l8VeKas0VZtfIInguJGIrMiPrwpXYddnRFit8Lt6ZxoXEOKZ5Ihi2KfD"><div class="choice-group" role="radiogroup"><ul class="radio-group-items"><li><input type="radio" id="collections-action-dialog-new" class="collections-new" name="collections" value="new" data-ga-category="collections_button" data-ga-action="click" data-ga-label="collections_radio_new"><label for="collections-action-dialog-new">Create a new collection</label></li><li><input type="radio" id="collections-action-dialog-existing" class="collections-existing" name="collections" value="existing" checked="true" data-ga-category="collections_button" data-ga-action="click" data-ga-label="collections_radio_existing"><label for="collections-action-dialog-existing">Add to an existing collection</label></li></ul></div><div class="controls-wrapper"><div class="action-panel-control-wrap new-collections-controls"><label for="collections-action-dialog-add-to-new" class="action-panel-label required-field-asterisk"> Name your collection: </label><input type="text" name="add-to-new-collection" id="collections-action-dialog-add-to-new" class="collections-action-add-to-new" pattern="[^"&=<>\/]*" title="The following characters are not allowed in the Name field: "&=<>/" maxlength="100" data-ga-category="collections_button" data-ga-action="create_collection" data-ga-label="non_favorties_collection"><div class="collections-new-name-too-long usa-input-error-message selection-validation-message"> Name must be less than 100 characters </div></div><div class="action-panel-control-wrap existing-collections-controls"><label for="collections-action-dialog-add-to-existing" class="action-panel-label"> Choose a collection: </label><select id="collections-action-dialog-add-to-existing" class="action-panel-selector collections-action-add-to-existing" data-ga-category="collections_button" data-ga-action="select_collection" data-ga-label="($('.collections-action-add-to-existing').val() === 'Favorites') ? 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class="article-details" id="article-details">   <header class="heading" id="heading"> <div class="full-view" id="full-view-heading"> <div class="article-citation"> <div class="article-source"> <div class="journal-actions dropdown-block"><button id="full-view-journal-trigger" class="journal-actions-trigger trigger" ref="linksrc=journal_actions_btn" title="American journal of respiratory and critical care medicine" tabindex="0" aria-controls="full-view-journal" aria-expanded="false" aria-label="Toggle dropdown menu for journal American journal of respiratory and critical care medicine" data-pinger-ignore> Am J Respir Crit Care Med </button><div id="full-view-journal" class="journal-actions-dropdown dropdown dropdown-container" hidden aria-label="Dropdown menu for journal American journal of respiratory and critical care medicine"><div class="title">Actions</div><div class="content"><ul class="journal-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link" href="/?term=%22Am+J+Respir+Crit+Care+Med%22%5Bjour%5D&sort=date&sort_order=desc" data-href="/?term=%22Am+J+Respir+Crit+Care+Med%22%5Bjour%5D&sort=date&sort_order=desc" ref="linksrc=search_in_pubmed_journal_name_link&journal_abbrev=Am J Respir Crit Care Med" data-ga-category="search" data-ga-action="journal_link" data-ga-label="Am J Respir Crit Care Med"> Search in PubMed </a></li><li><a class="search-in-nlm-catalog-link dropdown-block-link" ref ="linksrc=search_in_nlm_catalog_link" href="https://www.ncbi.nlm.nih.gov/nlmcatalog?term=%22Am+J+Respir+Crit+Care+Med%22%5BTitle+Abbreviation%5D" data-ga-category="search_catalog" data-ga-action="journal_link" data-ga-label="Am J Respir Crit Care Med"> Search in NLM Catalog </a></li><li><a class="add-to-search-link dropdown-block-link" ref ="linksrc=add_to_search_link" role="button" data-search-term='"Am J Respir Crit Care Med"[jour]' data-ga-category="search" data-ga-action="add_to_search" data-ga-label='"Am J Respir Crit Care Med"[jour]' href="#"> Add to Search </a></li></ul></div></div></div><span class="period">. </span><span class="cit">2021 Feb 15;203(4):414-423.</span> </div> <span class="citation-doi"> doi: 10.1164/rccm.202008-3328PP. </span> </div> <h1 class="heading-title"> From GOLD 0 to Pre-COPD </h1> <div class="inline-authors"> <div class="authors"> <div class="authors-list"> <span class="authors-list-item "><a class="full-name" href="/?term=Han+MK&cauthor_id=33211970" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="MeiLan K Han">MeiLan K Han</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Division of Pulmonary and Critical Care Medicine, University of Michigan, Ann Arbor, Michigan." href="#full-view-affiliation-1" ref="linksrc=author_aff"> 1 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Agusti+A&cauthor_id=33211970" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Alvar Agusti">Alvar Agusti</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Respiratory Institute, Hospital Clinic, University of Barcelona, August Pi i Sunyer Biomedical Research Institute, Biomedical Research Networking Center on Respiratory Diseases, Madrid, Spain." href="#full-view-affiliation-2" ref="linksrc=author_aff"> 2 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Celli+BR&cauthor_id=33211970" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Bartolome R Celli">Bartolome R Celli</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Department of Medicine, Pulmonary, Brigham and Women's Hospital, Boston, Massachusetts." href="#full-view-affiliation-3" ref="linksrc=author_aff"> 3 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Criner+GJ&cauthor_id=33211970" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Gerard J Criner">Gerard J Criner</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Department of Thoracic Medicine and Surgery, Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania." href="#full-view-affiliation-4" ref="linksrc=author_aff"> 4 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Halpin+DMG&cauthor_id=33211970" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="David M G Halpin">David M G Halpin</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="College of Medicine and Health, University of Exeter Medical School, University of Exeter, Exeter, United Kingdom." href="#full-view-affiliation-5" ref="linksrc=author_aff"> 5 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Roche+N&cauthor_id=33211970" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Nicolas Roche">Nicolas Roche</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Respiratory Medicine, Cochin Hospital, APHP.Centre-University of Paris, Cochin Institute (UMR1016), Paris, France." href="#full-view-affiliation-6" ref="linksrc=author_aff"> 6 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Papi+A&cauthor_id=33211970" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Alberto Papi">Alberto Papi</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Respiratory Division, Department of Translational Medicine, School of Medicine, University of Ferrara, Ferrera, Italy." href="#full-view-affiliation-7" ref="linksrc=author_aff"> 7 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Stockley+RA&cauthor_id=33211970" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Robert A Stockley">Robert A Stockley</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Lung Investigation Unit, Queen Elizabeth Hospital Birmingham, University Hospitals Birmingham National Health Service Foundation Trust, Birmingham, United Kingdom." href="#full-view-affiliation-8" ref="linksrc=author_aff"> 8 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Wedzicha+J&cauthor_id=33211970" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Jadwiga Wedzicha">Jadwiga Wedzicha</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Airway Disease Section, National Heart and Lung Institute, Imperial College, London, United Kingdom; and." href="#full-view-affiliation-9" ref="linksrc=author_aff"> 9 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Vogelmeier+CF&cauthor_id=33211970" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Claus F Vogelmeier">Claus F Vogelmeier</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Department of Medicine, Pulmonary and Critical Care Medicine, University Medical Center Giessen and Marburg, member of the German Center for Lung Research (DZL), Philipps-University, Marburg, Germany." href="#full-view-affiliation-10" ref="linksrc=author_aff"> 10 </a></sup></span> </div> </div> </div> <div class="short-article-details"> Affiliations <button class="more-details" id="toggle-authors" data-alt-text="Collapse" aria-controls="expanded-authors" aria-expanded="false" data-pinger-ignore data-fetch-url="/33211970/long-authors/" data-id-prefix=""> <span class="title"> Expand </span> </button> </div> <div class="extended-article-details" id="expanded-authors" aria-hidden="true"> <div class="expanded-authors" id="full-view-expanded-authors"> <div class="affiliations"> <h3 class="title"> Affiliations </h3> <ul class="item-list"> <li data-affiliation-id="full-view-affiliation-1" id="full-view-affiliation-1" ><sup class="key">1</sup> Division of Pulmonary and Critical Care Medicine, University of Michigan, Ann Arbor, Michigan.</li> <li data-affiliation-id="full-view-affiliation-2" id="full-view-affiliation-2" ><sup class="key">2</sup> Respiratory Institute, Hospital Clinic, University of Barcelona, August Pi i Sunyer Biomedical Research Institute, Biomedical Research Networking Center on Respiratory Diseases, Madrid, Spain.</li> <li data-affiliation-id="full-view-affiliation-3" id="full-view-affiliation-3" ><sup class="key">3</sup> Department of Medicine, Pulmonary, Brigham and Women's Hospital, Boston, Massachusetts.</li> <li data-affiliation-id="full-view-affiliation-4" id="full-view-affiliation-4" ><sup class="key">4</sup> Department of Thoracic Medicine and Surgery, Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania.</li> <li data-affiliation-id="full-view-affiliation-5" id="full-view-affiliation-5" ><sup class="key">5</sup> College of Medicine and Health, University of Exeter Medical School, University of Exeter, Exeter, United Kingdom.</li> <li data-affiliation-id="full-view-affiliation-6" id="full-view-affiliation-6" ><sup class="key">6</sup> Respiratory Medicine, Cochin Hospital, APHP.Centre-University of Paris, Cochin Institute (UMR1016), Paris, France.</li> <li data-affiliation-id="full-view-affiliation-7" id="full-view-affiliation-7" ><sup class="key">7</sup> Respiratory Division, Department of Translational Medicine, School of Medicine, University of Ferrara, Ferrera, Italy.</li> <li data-affiliation-id="full-view-affiliation-8" id="full-view-affiliation-8" ><sup class="key">8</sup> Lung Investigation Unit, Queen Elizabeth Hospital Birmingham, University Hospitals Birmingham National Health Service Foundation Trust, Birmingham, United Kingdom.</li> <li data-affiliation-id="full-view-affiliation-9" id="full-view-affiliation-9" ><sup class="key">9</sup> Airway Disease Section, National Heart and Lung Institute, Imperial College, London, United Kingdom; and.</li> <li data-affiliation-id="full-view-affiliation-10" id="full-view-affiliation-10" ><sup class="key">10</sup> Department of Medicine, Pulmonary and Critical Care Medicine, University Medical Center Giessen and Marburg, member of the German Center for Lung Research (DZL), Philipps-University, Marburg, Germany.</li> </ul> </div> </div> </div> <ul class="identifiers" id="full-view-identifiers"> <li> <span class="identifier pubmed"> <span class="id-label"> PMID: </span> <strong class="current-id" title="PubMed ID">33211970</strong> </span> </li> <li> <span class="identifier pmc"> <span class="id-label"> PMCID: </span> <a class="id-link" target="_blank" rel="noopener" ref="linksrc=article_id_link&article_id=PMC7885837&id_type=PMC" href="https://pmc.ncbi.nlm.nih.gov/articles/PMC7885837/" data-ga-category="full_text" data-ga-action="PMCID" > PMC7885837 </a> </span> </li> <li> <span class="identifier doi"> <span class="id-label"> DOI: </span> <a class="id-link" target="_blank" rel="noopener" ref="linksrc=article_id_link&article_id=10.1164/rccm.202008-3328PP&id_type=DOI" href="https://doi.org/10.1164/rccm.202008-3328pp" data-ga-category="full_text" data-ga-action="DOI" > 10.1164/rccm.202008-3328PP </a> </span> </li> </ul> <div class="in-clipboard-label " hidden> Item in Clipboard </div> </div> <div class="short-view" id="short-view-heading"> <h1 class="heading-title"> From GOLD 0 to Pre-COPD </h1> <div class="short-citation"> <span class="authors-list"> <span class="authors-list-item "><span class="full-name">MeiLan K Han</span><span class="citation-separator"> et al.</span></span> </span> <span class="citation-journal"> Am J Respir Crit Care Med<span class="citation-separator">.</span> </span> <span class="date"> <time class="citation-year" datetime="2021">2021</time><span class="citation-separator">.</span> </span> </div> <div class="more-article-details-section with-display-settings"> <button class="more-article-details" id="toggle-article-details" data-alt-text="Hide 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href="#"> Add to Search </a></li></ul></div></div></div><span class="period">. </span><span class="cit">2021 Feb 15;203(4):414-423.</span> </div> <span class="citation-doi"> doi: 10.1164/rccm.202008-3328PP. </span> </div> <div class="expanded-authors" id="short-view-expanded-authors"> <div class="authors"> <h3 class="title"> Authors </h3> <div class="authors-list"> <span class="authors-list-item "><a class="full-name" href="/?term=Han+MK&cauthor_id=33211970" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="MeiLan K Han">MeiLan K Han</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Division of Pulmonary and Critical Care Medicine, University of Michigan, Ann Arbor, Michigan." href="#short-view-affiliation-1" ref="linksrc=author_aff"> 1 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Agusti+A&cauthor_id=33211970" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Alvar Agusti">Alvar Agusti</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Respiratory Institute, Hospital Clinic, University of Barcelona, August Pi i Sunyer Biomedical Research Institute, Biomedical Research Networking Center on Respiratory Diseases, Madrid, Spain." href="#short-view-affiliation-2" ref="linksrc=author_aff"> 2 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Celli+BR&cauthor_id=33211970" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Bartolome R Celli">Bartolome R Celli</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Department of Medicine, Pulmonary, Brigham and Women's Hospital, Boston, Massachusetts." href="#short-view-affiliation-3" ref="linksrc=author_aff"> 3 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Criner+GJ&cauthor_id=33211970" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Gerard J Criner">Gerard J Criner</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Department of Thoracic Medicine and Surgery, Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania." href="#short-view-affiliation-4" ref="linksrc=author_aff"> 4 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Halpin+DMG&cauthor_id=33211970" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="David M G Halpin">David M G Halpin</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="College of Medicine and Health, University of Exeter Medical School, University of Exeter, Exeter, United Kingdom." href="#short-view-affiliation-5" ref="linksrc=author_aff"> 5 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Roche+N&cauthor_id=33211970" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Nicolas Roche">Nicolas Roche</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Respiratory Medicine, Cochin Hospital, APHP.Centre-University of Paris, Cochin Institute (UMR1016), Paris, France." href="#short-view-affiliation-6" ref="linksrc=author_aff"> 6 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Papi+A&cauthor_id=33211970" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Alberto Papi">Alberto Papi</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Respiratory Division, Department of Translational Medicine, School of Medicine, University of Ferrara, Ferrera, Italy." href="#short-view-affiliation-7" ref="linksrc=author_aff"> 7 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Stockley+RA&cauthor_id=33211970" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Robert A Stockley">Robert A Stockley</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Lung Investigation Unit, Queen Elizabeth Hospital Birmingham, University Hospitals Birmingham National Health Service Foundation Trust, Birmingham, United Kingdom." href="#short-view-affiliation-8" ref="linksrc=author_aff"> 8 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Wedzicha+J&cauthor_id=33211970" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Jadwiga Wedzicha">Jadwiga Wedzicha</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Airway Disease Section, National Heart and Lung Institute, Imperial College, London, United Kingdom; and." href="#short-view-affiliation-9" ref="linksrc=author_aff"> 9 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Vogelmeier+CF&cauthor_id=33211970" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Claus F Vogelmeier">Claus F Vogelmeier</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Department of Medicine, Pulmonary and Critical Care Medicine, University Medical Center Giessen and Marburg, member of the German Center for Lung Research (DZL), Philipps-University, Marburg, Germany." href="#short-view-affiliation-10" ref="linksrc=author_aff"> 10 </a></sup></span> </div> </div> <div class="affiliations"> <h3 class="title"> Affiliations </h3> <ul class="item-list"> <li data-affiliation-id="short-view-affiliation-1" id="short-view-affiliation-1" ><sup class="key">1</sup> Division of Pulmonary and Critical Care Medicine, University of Michigan, Ann Arbor, Michigan.</li> <li data-affiliation-id="short-view-affiliation-2" id="short-view-affiliation-2" ><sup class="key">2</sup> Respiratory Institute, Hospital Clinic, University of Barcelona, August Pi i Sunyer Biomedical Research Institute, Biomedical Research Networking Center on Respiratory Diseases, Madrid, Spain.</li> <li data-affiliation-id="short-view-affiliation-3" id="short-view-affiliation-3" ><sup class="key">3</sup> Department of Medicine, Pulmonary, Brigham and Women's Hospital, Boston, Massachusetts.</li> <li data-affiliation-id="short-view-affiliation-4" id="short-view-affiliation-4" ><sup class="key">4</sup> Department of Thoracic Medicine and Surgery, Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania.</li> <li data-affiliation-id="short-view-affiliation-5" id="short-view-affiliation-5" ><sup class="key">5</sup> College of Medicine and Health, University of Exeter Medical School, University of Exeter, Exeter, United Kingdom.</li> <li data-affiliation-id="short-view-affiliation-6" id="short-view-affiliation-6" ><sup class="key">6</sup> Respiratory Medicine, Cochin Hospital, APHP.Centre-University of Paris, Cochin Institute (UMR1016), Paris, France.</li> <li data-affiliation-id="short-view-affiliation-7" id="short-view-affiliation-7" ><sup class="key">7</sup> Respiratory Division, Department of Translational Medicine, School of Medicine, University of Ferrara, Ferrera, Italy.</li> <li data-affiliation-id="short-view-affiliation-8" id="short-view-affiliation-8" ><sup class="key">8</sup> Lung Investigation Unit, Queen Elizabeth Hospital Birmingham, University Hospitals Birmingham National Health Service Foundation Trust, Birmingham, United Kingdom.</li> <li data-affiliation-id="short-view-affiliation-9" id="short-view-affiliation-9" ><sup class="key">9</sup> Airway Disease Section, National Heart and Lung Institute, Imperial College, London, United Kingdom; and.</li> <li data-affiliation-id="short-view-affiliation-10" id="short-view-affiliation-10" ><sup class="key">10</sup> Department of Medicine, Pulmonary and Critical Care Medicine, University Medical Center Giessen and Marburg, member of the German Center for Lung Research (DZL), Philipps-University, Marburg, Germany.</li> </ul> </div> </div> <ul class="identifiers" id="short-view-identifiers"> <li> <span class="identifier pubmed"> <span class="id-label"> PMID: </span> <strong class="current-id" 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href="https://cdn.ncbi.nlm.nih.gov/pmc/blobs/ec81/7885837/5d88a8e63895/rccm.202008-3328PPf1.jpg" itemprop="contentUrl" aria-describedby="figure-caption-0" role="button" data-image-width="830" data-image-height="664" data-image-alt="Figure 1." data-pmc-id="PMC7885837" data-figure-id="fig1"> <img class="figure-thumb" itemprop="thumbnail" id="article-image-0" src="https://cdn.ncbi.nlm.nih.gov/pmc/blobs/ec81/7885837/1ed764b2cfec/rccm.202008-3328PPf1.gif" alt="Figure 1." /> </a> <meta itemprop="width" itemtype="http://schema.org/ImageObject" content="830"> <meta itemprop="height" itemtype="http://schema.org/ImageObject" content="664"> <div class="figure-caption figure-caption-text" itemtype="http://schema.org/ImageObject" itemprop="caption" aria-hidden="true"> <div class="caption-wrap"> <strong class="figure-label"> <p> Figure 1. </p> </strong> <div class="figure-caption-contents"><p> Conceptualized understanding of the relationships… </p></div> </div> </div> <div class="figure-caption-medium figure-caption-text" aria-hidden="true"> <strong class="figure-label"> <p> Figure 1. </p> </strong> <div class="figure-caption-contents"><p> Conceptualized understanding of the relationships among symptoms, structure, and function with respect to… </p></div> </div> <figcaption id="figure-caption-0" class="figure-caption-full figure-caption-text" itemtype="http://schema.org/ImageObject" itemprop="description"> <strong class="figure-label"> Figure 1. </strong> <div class="figure-caption-contents">Conceptualized understanding of the relationships among symptoms, structure, and function with respect to pre-COPD. COPD = chronic obstructive pulmonary disease; CT = computed tomography.</div> </figcaption> </figure> </div>  <div class="pswp figures-dialog" id="figures-dialog" tabindex="-1" role="dialog" aria-hidden="true" data-image-gallery-uid="article-figures" aria-label="Figures Dialog">  <div class="pswp__bg"></div>  <div class="pswp__scroll-wrap">  <div class="pswp__container"> <div class="pswp__item"></div> <div class="pswp__item"></div> <div class="pswp__item"></div> </div>  <div class="pswp__ui pswp__ui--hidden"> <div class="pswp__top-bar">  <div class="pswp__counter"></div> <button class="pswp__button pswp__button--close" title="Close (Esc)"></button> <button class="pswp__button pswp__button--share" title="Share"></button> <button class="pswp__button pswp__button--fs" title="Toggle fullscreen"></button> <button class="pswp__button pswp__button--zoom" title="Zoom in/out"></button>   <div class="pswp__preloader"> <div class="pswp__preloader__icn"> <div class="pswp__preloader__cut"> <div 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Am J Respir Crit Care Med. 2006;173:1316–1325. - <a class="reference-link" href="/16556696/" ref="linksrc=references_link&ordinalpos=1" data-ga-category="reference" data-ga-action="16556696" > PubMed </a> </li> </ol> </li> </ol> <div class="actions-bar"> <button class="show-all" ref="linksrc=show_all_references_link" aria-controls="top-references-list-1" data-next-page-url="/33211970/references/" data-ga-category="reference" data-ga-action="show_more" > Show all 58 references </button> </div> </div> </div> </div> <div id="publication-types" class="publication-types keywords-section"> <h2 class="title"> Publication types </h2> <ul class="keywords-list"><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link" aria-label="Toggle dropdown menu for keyword Research Support, N.I.H., Extramural" tabindex="0" aria-controls="keyword-actions-publication-types-0" aria-expanded="false" data-pinger-ignore> Research Support, N.I.H., Extramural 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href="https://www.ncbi.nlm.nih.gov/mesh?term=Forced+Expiratory+Volume" data-ga-category="search_mesh" data-ga-action="mesh_term_link" data-ga-label="Forced Expiratory Volume / drug effects*"> Search in MeSH </a></li><li><a class="add-to-search-link dropdown-block-link" ref="linksrc=add_to_search_link" role="button" data-search-term=""Forced Expiratory Volume/drug effects"[MAJR]" data-ga-category="search" data-ga-action="add_to_search" data-ga-label=""Forced Expiratory Volume/drug effects"[MAJR]" href="#"> Add to Search </a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link" aria-label="Toggle dropdown menu for keyword Humans" tabindex="0" aria-controls="keyword-actions-mesh-terms-7" aria-expanded="false" data-pinger-ignore> Humans </button><div id="keyword-actions-mesh-terms-7" class="keyword-actions-dropdown dropdown dropdown-container" hidden aria-label="Dropdown menu for keyword Humans"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link" href="/?term=%22Humans%22%5BMeSH%5D&sort=date&sort_order=desc" data-href="/?term=%22Humans%22%5BMeSH%5D&sort=date&sort_order=desc" ref="linksrc=search_in_pubmed_keyword_link&mesh="Humans"[MeSH]" data-ga-category="search" data-ga-action="mesh_term" data-ga-label="Humans"> Search in PubMed </a></li><li><a class="search-in-mesh-link dropdown-block-link" ref="linksrc=search_in_mesh_link" href="https://www.ncbi.nlm.nih.gov/mesh?term=Humans" data-ga-category="search_mesh" data-ga-action="mesh_term_link" data-ga-label="Humans"> Search in MeSH </a></li><li><a class="add-to-search-link dropdown-block-link" ref="linksrc=add_to_search_link" role="button" data-search-term=""Humans"[MeSH]" data-ga-category="search" data-ga-action="add_to_search" data-ga-label=""Humans"[MeSH]" href="#"> Add to Search </a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link" aria-label="Toggle dropdown menu for keyword Male" tabindex="0" aria-controls="keyword-actions-mesh-terms-8" aria-expanded="false" data-pinger-ignore> Male </button><div id="keyword-actions-mesh-terms-8" class="keyword-actions-dropdown dropdown dropdown-container" hidden aria-label="Dropdown menu for keyword Male"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link" href="/?term=%22Male%22%5BMeSH%5D&sort=date&sort_order=desc" data-href="/?term=%22Male%22%5BMeSH%5D&sort=date&sort_order=desc" ref="linksrc=search_in_pubmed_keyword_link&mesh="Male"[MeSH]" data-ga-category="search" data-ga-action="mesh_term" data-ga-label="Male"> Search in PubMed </a></li><li><a class="search-in-mesh-link dropdown-block-link" ref="linksrc=search_in_mesh_link" href="https://www.ncbi.nlm.nih.gov/mesh?term=Male" data-ga-category="search_mesh" data-ga-action="mesh_term_link" data-ga-label="Male"> Search in MeSH </a></li><li><a class="add-to-search-link dropdown-block-link" ref="linksrc=add_to_search_link" role="button" data-search-term=""Male"[MeSH]" data-ga-category="search" data-ga-action="add_to_search" data-ga-label=""Male"[MeSH]" href="#"> Add to Search </a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link" aria-label="Toggle dropdown menu for keyword Middle Aged" tabindex="0" aria-controls="keyword-actions-mesh-terms-9" aria-expanded="false" data-pinger-ignore> Middle Aged </button><div id="keyword-actions-mesh-terms-9" class="keyword-actions-dropdown dropdown dropdown-container" hidden aria-label="Dropdown menu for keyword Middle Aged"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link" href="/?term=%22Middle+Aged%22%5BMeSH%5D&sort=date&sort_order=desc" data-href="/?term=%22Middle+Aged%22%5BMeSH%5D&sort=date&sort_order=desc" ref="linksrc=search_in_pubmed_keyword_link&mesh="Middle Aged"[MeSH]" data-ga-category="search" data-ga-action="mesh_term" data-ga-label="Middle Aged"> Search in PubMed </a></li><li><a class="search-in-mesh-link dropdown-block-link" ref="linksrc=search_in_mesh_link" href="https://www.ncbi.nlm.nih.gov/mesh?term=Middle+Aged" data-ga-category="search_mesh" data-ga-action="mesh_term_link" data-ga-label="Middle Aged"> Search in MeSH </a></li><li><a class="add-to-search-link dropdown-block-link" ref="linksrc=add_to_search_link" role="button" data-search-term=""Middle Aged"[MeSH]" data-ga-category="search" data-ga-action="add_to_search" data-ga-label=""Middle Aged"[MeSH]" href="#"> Add to Search </a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link major" aria-label="Toggle dropdown menu for keyword Pulmonary Disease, Chronic Obstructive / diagnosis*" tabindex="0" aria-controls="keyword-actions-mesh-terms-major-10" aria-expanded="false" data-pinger-ignore> Pulmonary Disease, Chronic Obstructive / diagnosis* </button><div id="keyword-actions-mesh-terms-major-10" class="keyword-actions-dropdown dropdown dropdown-container" hidden aria-label="Dropdown menu for keyword Pulmonary Disease, Chronic Obstructive / diagnosis*"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link" href="/?term=%22Pulmonary+Disease%2C+Chronic+Obstructive%2Fdiagnosis%22%5BMAJR%5D&sort=date&sort_order=desc" data-href="/?term=%22Pulmonary+Disease%2C+Chronic+Obstructive%2Fdiagnosis%22%5BMAJR%5D&sort=date&sort_order=desc" ref="linksrc=search_in_pubmed_keyword_link&mesh="Pulmonary Disease, Chronic Obstructive/diagnosis"[MAJR]" data-ga-category="search" data-ga-action="mesh_term" 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therapy*" tabindex="0" aria-controls="keyword-actions-mesh-terms-major-11" aria-expanded="false" data-pinger-ignore> Pulmonary Disease, Chronic Obstructive / drug therapy* </button><div id="keyword-actions-mesh-terms-major-11" class="keyword-actions-dropdown dropdown dropdown-container" hidden aria-label="Dropdown menu for keyword Pulmonary Disease, Chronic Obstructive / drug therapy*"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link" href="/?term=%22Pulmonary+Disease%2C+Chronic+Obstructive%2Fdrug+therapy%22%5BMAJR%5D&sort=date&sort_order=desc" data-href="/?term=%22Pulmonary+Disease%2C+Chronic+Obstructive%2Fdrug+therapy%22%5BMAJR%5D&sort=date&sort_order=desc" ref="linksrc=search_in_pubmed_keyword_link&mesh="Pulmonary Disease, Chronic Obstructive/drug therapy"[MAJR]" data-ga-category="search" data-ga-action="mesh_term" data-ga-label="Pulmonary Disease, Chronic Obstructive / drug therapy*"> 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aria-controls="keyword-actions-mesh-terms-major-12" aria-expanded="false" data-pinger-ignore> Pulmonary Disease, Chronic Obstructive / physiopathology* </button><div id="keyword-actions-mesh-terms-major-12" class="keyword-actions-dropdown dropdown dropdown-container" hidden aria-label="Dropdown menu for keyword Pulmonary Disease, Chronic Obstructive / physiopathology*"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link" href="/?term=%22Pulmonary+Disease%2C+Chronic+Obstructive%2Fphysiopathology%22%5BMAJR%5D&sort=date&sort_order=desc" data-href="/?term=%22Pulmonary+Disease%2C+Chronic+Obstructive%2Fphysiopathology%22%5BMAJR%5D&sort=date&sort_order=desc" ref="linksrc=search_in_pubmed_keyword_link&mesh="Pulmonary Disease, Chronic Obstructive/physiopathology"[MAJR]" data-ga-category="search" data-ga-action="mesh_term" data-ga-label="Pulmonary Disease, Chronic Obstructive / physiopathology*"> Search in 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data-pinger-ignore> Severity of Illness Index </button><div id="keyword-actions-mesh-terms-13" class="keyword-actions-dropdown dropdown dropdown-container" hidden aria-label="Dropdown menu for keyword Severity of Illness Index"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link" href="/?term=%22Severity+of+Illness+Index%22%5BMeSH%5D&sort=date&sort_order=desc" data-href="/?term=%22Severity+of+Illness+Index%22%5BMeSH%5D&sort=date&sort_order=desc" ref="linksrc=search_in_pubmed_keyword_link&mesh="Severity of Illness Index"[MeSH]" data-ga-category="search" data-ga-action="mesh_term" data-ga-label="Severity of Illness Index"> Search in PubMed </a></li><li><a class="search-in-mesh-link dropdown-block-link" ref="linksrc=search_in_mesh_link" href="https://www.ncbi.nlm.nih.gov/mesh?term=Severity+of+Illness+Index" data-ga-category="search_mesh" data-ga-action="mesh_term_link" data-ga-label="Severity of Illness Index"> Search in MeSH </a></li><li><a class="add-to-search-link dropdown-block-link" ref="linksrc=add_to_search_link" role="button" data-search-term=""Severity of Illness Index"[MeSH]" data-ga-category="search" data-ga-action="add_to_search" data-ga-label=""Severity of Illness Index"[MeSH]" href="#"> Add to Search </a></li></ul></div></div></div></li></ul> </div> <div id="substances" class="substances keywords-section"> <h2 class="title"> Substances </h2> <ul class="keywords-list"><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link" aria-label="Toggle dropdown menu for keyword Biomarkers" tabindex="0" aria-controls="keyword-actions-substances-0" aria-expanded="false" data-pinger-ignore> Biomarkers </button><div id="keyword-actions-substances-0" class="keyword-actions-dropdown dropdown dropdown-container" hidden aria-label="Dropdown menu for keyword Biomarkers"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link" href="/?term=%22Biomarkers%22%5Bnm%5D&sort=date&sort_order=desc" data-href="/?term=%22Biomarkers%22%5Bnm%5D&sort=date&sort_order=desc" ref="linksrc=search_in_pubmed_keyword_link&keyword="Biomarkers"[nm]" data-ga-category="search" data-ga-action="substance" data-ga-label="Biomarkers"> Search in PubMed </a></li><li><a class="search-in-mesh-link dropdown-block-link" ref="linksrc=search_in_mesh_link" href="https://www.ncbi.nlm.nih.gov/mesh?term=%22Biomarkers%22" data-ga-category="search_mesh" data-ga-action="substance_link" data-ga-label="Biomarkers"> Search in MeSH </a></li><li><a class="add-to-search-link dropdown-block-link" ref="linksrc=add_to_search_link" role="button" data-search-term=""Biomarkers"[nm]" data-ga-category="search" data-ga-action="add_to_search" data-ga-label=""Biomarkers"[nm]" href="#"> Add to Search </a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link" aria-label="Toggle dropdown menu for keyword Bronchodilator Agents" tabindex="0" aria-controls="keyword-actions-substances-1" aria-expanded="false" data-pinger-ignore> Bronchodilator Agents </button><div id="keyword-actions-substances-1" class="keyword-actions-dropdown dropdown dropdown-container" hidden aria-label="Dropdown menu for keyword Bronchodilator Agents"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link" href="/?term=%22Bronchodilator+Agents%22%5Bnm%5D&sort=date&sort_order=desc" data-href="/?term=%22Bronchodilator+Agents%22%5Bnm%5D&sort=date&sort_order=desc" ref="linksrc=search_in_pubmed_keyword_link&keyword="Bronchodilator Agents"[nm]" data-ga-category="search" data-ga-action="substance" data-ga-label="Bronchodilator Agents"> Search in PubMed </a></li><li><a class="search-in-mesh-link dropdown-block-link" 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