title: Short-term change in self-reported COPD symptoms after smoking cessation in an internet sample.
abstract: Smoking is the first risk factor for chronic obstructive pulmonary disease (COPD). Some recent reports suggest that, unexpectedly, some respiratory symptoms may increase transiently after smoking cessation, but there is a dearth of short-term data to test this hypothesis. The aim of the present study was to assess the validity of an online screening tool and to describe short-term associations between smoking behaviour and self-reported respiratory symptoms, in cross-sectional and longitudinal data. An internet survey was conducted in 2003-2009, on a smoking cessation website, with a follow-up survey after 30 days. There were 15,916 participants at baseline and 1,831 at follow-up. In the 252 baseline smokers who had quit smoking at 30-day follow-up, there was a substantial decrease in the proportion of participants who declared that they often coughed even without a cold (from 51.6% at baseline to 15.5% at follow-up), expectorated when they coughed in the morning (from 47.6% to 19.4%), were out of breath after climbing stairs or after a quick walk (from 75.0% to 48.4%), and who had a wheezing respiration (from 33.7% to 10.3%) (p<0.001 for all before/after comparisons). In participants who did not change their smoking behaviour between assessments, the test-retest reliability was r = 0.87 for a score summing these four symptoms. Smoking cessation was followed by a rapid and substantial improvement in self-reported respiratory symptoms. COPD is largely underdiagnosed and undertreated. Internet screening is reliable and may allow for the early detection of COPD symptoms at a large scale, in patients who may otherwise have no access to COPD case-finding efforts.
authors.affiliation: Institute of Social and Preventive Medicine, University of Geneva, CMU, 1 rue Michel-Servet, CH-1211 Geneva 4, Switzerland. Jean-Francois.Etter@unige.ch
authors.forename: J-F
authors.initials: JF
authors.lastname: Etter
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D005240:Feasibility Studies; D005260:Female; D005500:Follow-Up Studies; D006306:Health Surveys; D006801:Humans; D020407:Internet / Q000706:statistics & numerical data*; D008297:Male; D008403:Mass Screening / Q000379:methods / Q000592:standards*; D009042:Motivation; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis* / Q000453:epidemiology*; D015203:Reproducibility of Results; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology*; D016540:Smoking Cessation / Q000706:statistics & numerical data*; D011795:Surveys and Questionnaires / Q000592:standards