Education as a modifier of familial transmission of cigarette smoking

Studies of smoking cessation indicate probability of quitting increases with level of education. Behavioral genetic studies indicate persistence of smoking is influenced by genetic factors. We test the hypothesis that level of education is a modifier of familial transmission for cessation. Data come from the Health and Adjustment of Young Adults Study, a longitudinal study of 1,007 adults, 21-30 years of age. Family history of 'regular smoking' and quitting for a year or more were assessed for biological parents and full siblings. Familial loading was measured as the proportion of 1st degree relatives who had ever quit for a year or more. Among proband daily smokers quitting was defined as not having smoked for at least one year. Evidence supported the familial transmission of smoking cessation among Caucasians (current smokers = 0.48 vs. 0.58 for quitters, p = 0.02) but not African Americans (0.44 vs. 0.42, p = 0.81). Familial transmission of smoking cessation among those with a high school or lower education was significant (0.40 vs. 0.62, p = 0.006) but not for those with some college (0.51 vs. 0.54, p = 0.69) or those with a college degree or more (0.56 vs. 0.59, p = 0.70). Results suggest that for daily smokers with greater than a high school education familial loading has little influence on likelihood of quitting, in contrast to those with less education.