LAUSR

BACKGROUND AND AIMS Among European countries, France is particularly concerned by adolescent tobacco smoking, especially in disadvantaged socio-economic backgrounds (SES). We measured the respective contributions of parental smoking and family living arrangement to social disparities in smoking during adolescence. DESIGN Secondary analysis of survey data. SETTING A cross-sectional nationwide exhaustive 12-day survey in March 2017 of French youth aged 17-18.5 participating in the national mandatory civic information day. PARTICIPANTS 13,314 adolescents answering a pen and paper questionnaire about their own tobacco consumption and the smoking of their parents. MEASUREMENTS Risk-ratios (RRs) were computed using modified Poisson regressions, and population attributable fraction (PAF) was used as a measure of the explanatory roles of the different factors as mediators of SES. FINDINGS Adolescents living in very privileged and privileged SES were significantly less likely to report daily tobacco smoking (20.4% and 22.7%, respectively) than those in modest and disadvantaged ones (26.0% and 28.6%, respectively). Parental smoking and family living arrangement independently explained the smoking inequalities among adolescents. After adjusting for schooling factors, the risks associated with parental smoking ranged between RR=1.64 [95% confidence interval=1.50-1.79] when the father only smoked and RR=2.17 [1.99-2.36] when both parents smoked, as compared with non-smoking parents; the risk associated with living in a non-intact family was 1.35 [1.26-1.43] and that of living outside parental home was 1.20 [1.10-1.30]. Apprentices and adolescents out of school had higher risks than those at school (RR=1.82 [1.68-1.98] and RR=2.10 [1.92-2.29]). The contribution of parental smoking to adolescent smoking (PAF=32%) was greater than that of SES (PAF=9%), family living arrangement (PAF=17%) or schooling factors (14%). The share of SES decreased from 18% to 9% when considering these mediating factors. CONCLUSION In France, parental smoking appears to be the factor that most influences adolescent smoking, followed by family living arrangement; the role of family socio-economic status is small in comparison.