Jaakkola M S, Jaakkola J J, Ernst P, Becklake M R
Dept of Pulmonary Medicine, Helsinki University Central Hospital, Finland.
Eur Respir J. 1991 Jun;4(6):643-50.
The objective of this study was to estimate the effect of cigarette smoking on ventilatory lung function among young adults with special emphasis on the recognition of susceptible subgroups. In a cross-sectional study of 1,044 adults aged 15-40 yrs, a statistically significant linear relationship between quantity of smoking in cigarette-years and level of forced expiratory volume in one second (FEV1) was found. Among current cigarette smokers, FEV1 level was on average 35 ml lower for each 100 cigarette-years of exposure (corresponding to smoking of ten cigarettes per day for 10 yrs) compared to lifelong nonsmokers in a linear regression adjusted for confounding. Potentially susceptible subgroups were studied by introducing interaction terms between quantitative smoking and gender, wheezing, atopy, asthma, childhood respiratory illness and exposure to environmental tobacco smoke during the growth period, to the additive linear regression model explaining the FEV1 level. Wheezing was found to modify the effect of smoking significantly: the FEV1 level was on average 68 ml lower for each 100 cigarette-years due to interaction between smoking and wheezing. An introduction of the interaction term eliminated the independent effect of smoking. The results suggest that the detrimental effect of smoking on FEV1 in young adults may be limited to individuals with wheezing. Thus, the presence of wheezing among smokers indicates a higher risk for low level of ventilatory lung function compared to smokers who do not wheeze.
本研究的目的是评估吸烟对年轻成年人肺通气功能的影响，特别着重于识别易感亚组。在一项对1044名年龄在15 - 40岁成年人的横断面研究中，发现吸烟量（以吸烟年数计）与一秒用力呼气量（FEV1）水平之间存在统计学上显著的线性关系。在当前吸烟者中，在对混杂因素进行线性回归调整后，与终身不吸烟者相比，每暴露100吸烟年，FEV1水平平均降低35毫升（相当于每天吸10支烟，持续10年）。通过在解释FEV1水平的加法线性回归模型中引入吸烟量与性别、喘息、特应性、哮喘、儿童期呼吸系统疾病以及生长期接触环境烟草烟雾之间的交互项，对潜在的易感亚组进行了研究。发现喘息会显著改变吸烟的影响：由于吸烟与喘息之间的相互作用，每100吸烟年FEV1水平平均降低68毫升。引入交互项消除了吸烟的独立影响。结果表明，吸烟对年轻成年人FEV1的有害影响可能仅限于有喘息症状的个体。因此，与无喘息的吸烟者相比，吸烟者中存在喘息表明肺通气功能水平较低的风险更高。
