How do educational disparities in smoking develop during early life? A Swedish longitudinal study.

Smoking contributes to health inequalities, but how social inequalities in smoking develop in early life remains unclear. This study examines how measures of education attained over the early life course (representing socioeconomic position of origin, socioeconomic position of destination, and in-between) contribute to smoking behavior in a Swedish longitudinal sample. We used data obtained from the Swedish Level-of-Living Surveys in addition to national register data. Young adults (aged 20-28, n = 749) self-reported their educational attainment and smoking behavior (initiation and cessation) in 2010. Ten years earlier, their parents self-reported their own education and smoking behavior. We used linked register data on school performance in adolescence (in grade 9). Logistic regression models showed that lower parental education, lower adolescent school performance, and low young adult educational attainment were respectively associated with young adult smoking initiation. The association between parental education and young adult smoking initiation was explained by adolescent school performance and not parental smoking. Young adult smoking cessation was associated with high parental education and high adolescent school performance (marks in the top quartile), but only school performance remained significant in the final model, which included all measures of education and parental smoking. Results suggest that school performance in adolescence (which connects adolescents' socioeconomic position of origin with their destination) may play an important role in how educational disparities in smoking form over the life course.