Driving kids to smoke? Children's reported exposure to smoke in cars and early smoking initiation.

The health risks associated with second hand smoke (SHS) are well-known. However, little is known about exposure to SHS in cars and risk of smoking uptake. This paper investigates the association between pre-adolescents reported exposure to smoking in cars and prevalence of early stage smoking activity. Data from Keeping Kids Smokefree baseline surveys of students were used to investigate smoking status and reported exposure to smoking in cars. Log binomial regression analyses were used to investigate if reported exposure to SHS in cars was associated with smoking prevalence. 83% of 5676 students invited took part. After controlling for all variables reported exposure to smoking in cars and homes were significantly associated with increased risk of initiated smoking (RR 1.87, 95% CI 1.43-2.44, and RR 1.5, 95% CI 1.13-1.97, respectively). Exposure to smoking in cars was substantially and significantly associated with risk of current smoking (RR 3.21, 95% CI 1.45-7.08). Early smoking uptake is associated with students' reported exposure to smoking in cars which confirms the importance of protecting children from SHS. Smoking in cars is under parental control and therefore modifiable. Moreover, children's reports of SHlS exposure offer a simple way of identifying families who can be targeted for tobacco control interventions.