Smokers with respiratory symptoms but no airflow limitation, often have activity limitation, exacerbations and evidence of airway disease.

Commentary on : Woodruff PG, Barr RG, Bleecker E, et al. Clinical significance of symptoms in smokers with preserved pulmonary function. N Engl J Med 2016;374:1811–21.[OpenUrl][1][CrossRef][2][PubMed][3] COPD is, according to the Global Initiative for Chronic Obstructive Lung Disease, defined as persistent airflow limitation, that is, the key diagnostic criterion is a postbronchodilator forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) ratio <0.70.1 However, this definition has clear limitations in clinical practice, as it does not take symptoms into account and only applies to individuals in whom fixed airflow limitation has developed.2 Furthermore, this diagnostic criterion, that is, FEV1/FVC ratio <0.70, is likely to be insensitive for recognition of early COPD.3 ,4 Some current or … [1]: {openurl}?query=rft.jtitle%253DN%2BEngl%2BJ%2BMed%26rft.volume%253D374%26rft.spage%253D1811%26rft_id%253Dinfo%253Adoi%252F10.1056%252FNEJMoa1505971%26rft_id%253Dinfo%253Apmid%252F27168432%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [2]: /lookup/external-ref?access_num=10.1056/NEJMoa1505971&link_type=DOI [3]: /lookup/external-ref?access_num=27168432&link_type=MED&atom=%2Febmed%2Fearly%2F2016%2F08%2F23%2Febmed-2016-110501.atom