Exposure-response relationship between paternal smoking and children's pulmonary function

We conducted a cross-sectional study to investigate paternal smoking and ch ildren's pulmonary function in rural communities of Anqing, China. Our anal ysis included 1,718 children 8 to 15 yr of age whose mothers were never-smo kers. Multiple linear regression models were used to estimate the effect of paternal smoking on children's pulmonary function, with adjustment for chi ldren's age, sex, weight, height, square of height, asthma, and father's ed ucation. When compared with children of never-smoking fathers, children of smoking fathers had small, but detectable deficits in FEV1 (-36 ml, SE = 20 ) and FVC (-37 ml, SE = 22). When children of smoking fathers were subdivid ed into two subgroups, father smoked <30 cigarettes/day and <greater than o r equal to>30 cigarettes/day, we found that children whose fathers smoked g reater than or equal to 30 cigarettes/day had the largest deficits in both FEV1 (-79 ml, SE = 30) and FVC (-71 ml, SE = 34). This monotonic exposure-r esponse relationship remained in all strata when we further stratified our analysis by children's sex and asthma status. Our data also suggested that the relationship was greatest among nonasthmatic girls, although neither se x nor asthma interaction terms were statistically significant. We conclude that there Is a monotonic exposure-response relationship between paternal s moking and decline of pulmonary function in children in this rural Chinese population.