Cook D G, Strachan D P
Department of Public Health Sciences, St George's Hospital Medical School, London, UK.
Thorax. 1997 Dec;52(12):1081-94. doi: 10.1136/thx.52.12.1081.
A systematic quantitative review of the evidence relating parental smoking to the prevalence of asthma and respiratory symptoms was conducted amongst school age children.
Sixty relevant studies were identified after consideration of 1593 articles selected by electronic search of the Embase and Medline databases using keywords relevant to passive smoking in children. The search was completed in April 1997 and identified 25 studies of asthma, 41 of wheeze, 34 of chronic cough, seven of chronic phlegm and six of breathlessness which were included in a quantitative overview.
The pooled odds ratios for either parent smoking were 1.21 (95% CI 1.10 to 1.34) for asthma, 1.24 (95% CI 1.17 to 1.31) for wheeze, 1.40 (95% CI 1.27 to 1.53) for cough, 1.35 (95% CI 1.13 to 1.62) for phlegm, and 1.31 (95% CI 1.08 to 1.59) for breathlessness. Adjustment for confounding had little effect. Evidence of heterogeneity between studies appeared largely explicable by publication bias with a superfluity of small studies with large odds ratios. However, excluding these had little effect on the pooled odds ratios. The prevalence of all symptoms increased with the number of parents who smoked. While maternal smoking had a greater effect than paternal smoking, the effect of father only was clearly significant.
The relationship between parental smoking and respiratory symptoms seems very likely to be causal given statistical significance, robustness to adjustment for confounding factors, consistency of the findings in different countries, and evidence of dose response. The raised risk in households where the father, but not the mother, smoked argues for a postnatal effect.
针对学龄儿童开展了一项系统性定量综述，以研究父母吸烟与哮喘及呼吸道症状患病率之间的证据关系。
通过使用与儿童被动吸烟相关的关键词，对Embase和Medline数据库进行电子检索，从1593篇文章中筛选出60项相关研究。检索于1997年4月完成，确定了25项关于哮喘的研究、41项关于喘息的研究、34项关于慢性咳嗽的研究、7项关于慢性咳痰的研究和6项关于气促的研究，并将其纳入定量综述。
父母任何一方吸烟的合并比值比，哮喘为1.21（95%可信区间1.10至1.34），喘息为1.24（95%可信区间1.17至1.31），咳嗽为1.40（95%可信区间1.27至1.53），咳痰为1.35（95%可信区间1.13至1.62），气促为1.31（95%可信区间1.08至1.59）。对混杂因素进行调整影响不大。研究间异质性的证据在很大程度上可通过发表偏倚来解释，存在大量比值比大的小型研究。然而，排除这些研究对合并比值比影响不大。所有症状的患病率均随吸烟父母的数量增加而升高。虽然母亲吸烟的影响大于父亲吸烟，但仅父亲吸烟的影响也明显显著。
鉴于具有统计学意义、对混杂因素调整的稳健性、不同国家研究结果的一致性以及剂量反应证据，父母吸烟与呼吸道症状之间的关系很可能是因果关系。父亲而非母亲吸烟的家庭中风险升高，这表明存在产后影响。
