title: Longitudinal study of parental smoking habits and development of asthma in early childhood.
abstract: OBJECTIVE
  This study examined the association between parental smoking habits and the development of asthma in early childhood by using representative samples.
  
  
  METHODS
  The survey subjects included all of the 53,575 babies born in Japan during the periods January 10-17 and July 10-17, 2001. The families of the subjects were asked to complete questionnaires that were delivered by post at 6 months, 1 year 6 months, 2 years 6 months, 3 years 6 months, and 4 years 6 months postpartum. The first survey contained questions regarding the smoking habits of the parents. The second to fifth surveys asked if the child had needed medical attention for the treatment of asthma.
  
  
  RESULTS
  Data from 36,888 subjects (collection rate: 68.9%) were analyzed. The 4-year cumulative incidence of asthma was 12.0%. Maternal indoor smoking significantly increased the risk of asthma development in children, 4-year risk 14.4% vs. 11.7%, risk ratio=1.24, 95% CI: 1.11 to 1.38. No statistically significant association was found between paternal smoking and asthma development in children.
  
  
  CONCLUSIONS
  In order to prevent the development of asthma in early childhood, it is necessary to formulate measures to stop or discourage maternal smoking.
authors: Division of Public Health, Department of Social Medicine, Nihon University School of Medicine, Tokyo, Japan.
authors: Miki
authors: M
authors: Kanoh
authors: Yoshitaka
authors: Y
authors: Kaneita
authors: Megumi
authors: M
authors: Hara
authors: Shohei
authors: S
authors: Harada
authors: Yasuhiro
authors: Y
authors: Gon
authors: Hiroshi
authors: H
authors: Kanamaru
authors: Takashi
authors: T
authors: Ohida
mesh_terms: D001249:Asthma / Q000209:etiology*; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007564:Japan / Q000453:epidemiology; D008137:Longitudinal Studies; D008297:Male; D010290:Parents; D012907:Smoking / Q000453:epidemiology*; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*
chemical_list: D014028:Tobacco Smoke Pollution