title: [The relationship between smoking and the incidence of COPD].
abstract: OBJECTIVE
  To study the relationship between smoking index and the incidence of COPD to persuade smokers quit smoking.
  
  
  METHODS
  COPD was diagnosed based on family inquiring, questionnaire and pulmonary function test. The smoking index was calculated by the average cigarettes a day times the years of smoking.
  
  
  RESULTS
  822 cases(account for 24.6% of investigated subjects) of COPD due to smoking were identified, and 624 cases were found (account for 40.4% of investegated subjects) to have a history of both smoking and chronic airway inflammation. The higher the smoking index, the higher the incidence of COPD (above 40%), and the more severe their lung function imparement. The smoking was 71.6% of the cause in COPD patients.
  
  
  CONCLUSIONS
  The incidence of COPD associated with smoking is higher in China than that in the Western countries. The incidence of COPD in population with long smoking history is not invariable, while it is gradually rising with increasing smoking index.
authors.affiliation: Fusoai Cardiovascular Hospital, CAMS & PUMC, Beijing 100037.
authors.forename: X
authors.initials: X
authors.lastname: Cheng
authors.forename: J
authors.initials: J
authors.lastname: Li
authors.forename: Z
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D002681:China / Q000453:epidemiology; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011159:Population Surveillance; D029424:Pulmonary Disease, Chronic Obstructive / Q000453:epidemiology* / Q000209:etiology; D012907:Smoking / Q000009:adverse effects*