Babies Living Safe and Smokefree (BLiSS) Intervention Reduces Children's Tobacco Smoke Exposure Directly and Indirectly by Improving Maternal Smokers' Urge Management Skills and Exposure Protection Behaviors.

Children's tobacco smoke exposure (CTSE) is a public health concern, particularly in low-income and minority communities. Interventions to reduce CTSE have had modest success, and so research must identify mechanisms to improve intervention efficacy. This study investigated mediators of CTSE reduction in an intervention designed to facilitate CTSE protection and maternal smoking abstinence. We analyzed data from the Babies Living Safe and Smokefree (BLiSS) trial, which evaluated the efficacy of a multilevel behavioral smoking intervention initiated in community clinics serving low-income mothers. We estimated direct and indirect effects to evaluate the role of two mediators of the intervention on CTSE at post-intervention follow-up: mothers' skills in managing smoking urges and their protective behaviors to shield children from TSE. CTSE was measured using mothers' reports and child cotinine (a CTSE biomarker). The BLiSS intervention was linked to statistically significant lower longitudinal reported CTSE directly and indirectly by increasing mothers' urge management skills and CTSE protection behaviors (p-values < 0.05). The intervention was not directly linked to child cotinine. However, evidence of a statistically significant indirect effect (p-value = 0.028) suggested that the intervention reduced longitudinal child cotinine levels by increasing CTSE protection behaviors. Two non-program factors, nicotine dependence and total smokers in the home, also increased child cotinine and reported CTSE (p-values < 0.001). Interventions that improve maternal smokers' urge management skills and CTSE protections can mitigate CTSE. In addition, it is essential to target barriers to CTSE reduction, such as nicotine dependence levels and the presence of other smokers in the home.