title: [Meta-analysis of the relationship between passive smoking population in China and lung cancer].
abstract: OBJECTIVE
  Studies of passive smoking exposure in China however are of particular interest, because of the high lung cancer rate in people who are mostly non-smokers. The aim of this study is to explore the relationship between passive smoking and lung cancer among non-smoking Chinese.
  
  
  METHODS
  By searching Medline, PubMed, CENTRAL (the Cochrane central register of controlled trials), CBM, CNKI and VIP, et al, we collected both domestic and overseas published documents between 1987 and 2007 on passive smoking and lung cancer among non-smoking Chinese. Random or fixed effect models were applied to conduct meta-analysis on the case control study results, and the combined odds ratio (OR) and the 95% confidence interval (CI) were calculated as well.
  
  
  RESULTS
  Sixteen documents were included into the combined analysis, which indicated that there was statistical significance between passive smoking and lung cancer (OR = 1.13, 95% CI: 1.05-1.21, P = 0.001). It was significant of lung cancer among non-smoking subjects associated with amount of tobacco passively smoked more than 20 cigarettes daily, with life period in adulthood passive smoking exposure, with gender female, and with exposure to workplace. The P value, OR and 95% CI were P = 0.0003, OR = 1.78, 95% CI: 1.30-2.43; P = 0.0001, OR = 1.50, 95% CI: 1.23-1.83; P = 0.000 7, OR = 1.50, 95% CI: 1.19-1.90; P < 0.0001, OR = 1.41, 95% CI: 1.19-1.66; respectively. And there was no significant difference between passive smoking and lung cancer with amount of tobacco passively smoked within 20 cigarettes daily, with life period in childhood passive smoking exposure, with gender male and with exposure to spouse and parents.
  
  
  CONCLUSIONS
  Passive smoking is an important risk factor of lung cancer among non-smoking Chinese, and for non-smoking women who expose to environment tobacco smoke in a long period of time have a close relationship with lung cancer risk.
authors.affiliation: Department of Thoracic Surgery, Tianjin People's Hospital, Tianjin 300121, China. zhaohui0089@sina.com
authors.forename: Hui
authors.initials: H
authors.lastname: Zhao
authors.forename: Jundong
authors.initials: J
authors.lastname: Gu
authors.forename: Hongrui
authors.initials: H
authors.lastname: Xu
authors.forename: Bingjun
authors.initials: B
authors.lastname: Yang
authors.forename: Youkui
authors.initials: Y
authors.lastname: Han
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.forename: Shuzhong
authors.initials: S
authors.lastname: Liu
authors.forename: Hong
authors.initials: H
authors.lastname: Yao
mesh_terms: D002681:China / Q000453:epidemiology; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000209:etiology*; D008297:Male; D012307:Risk Factors; D014028:Tobacco Smoke Pollution / Q000009:adverse effects* / Q000706:statistics & numerical data
chemical_list: D014028:Tobacco Smoke Pollution