Multilevel Intervention for Low-Income Maternal Smokers in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC).

To test the efficacy of Babies Living Safe and Smokefree (BLiSS), a multilevel intervention initiated in a citywide safety net health system to improve low-income maternal smokers' abstinence and reduce child tobacco smoke exposure. This randomized controlled trial in Philadelphia, Pennsylvania (2015-2020), recruited low-income maternal smokers who received a brief smoking intervention (Ask, Advise, Refer [AAR]) from nutrition professionals in the Special Supplemental Nutrition Program for Women, Infants, and Children before randomization to (1) a multilevel intervention (AAR + multimodal behavioral intervention [MBI]; n = 199) or (2) an attention control intervention (AAR + control; n = 197). AAR + MBI mothers had significantly higher 12-month bioverified abstinence rates than did AAR + control mothers (odds ratio [OR] = 9.55; 95% confidence interval [CI] = 1.54, 59.30;  = .015). There were significant effects of time (b = -0.15; SE = 0.04;  < .001) and condition by time (b = -0.19; SE = 0.06;  < .001) on reported child exposure favoring AAR + MBI, but no group difference in child cotinine. Presence of other residential smokers was related to higher exposure. Higher baseline nicotine dependence was related to higher child exposure and lower abstinence likelihood at follow-up. The multilevel BLiSS intervention was acceptable and efficacious in a population that experiences elevated challenges with cessation. BLiSS is a translatable intervention model that can successfully improve efforts to address the persistent tobacco-related burdens in low-income communities. Clinical Trials.gov identifier: NCT02602288. (. 2022;112(3):472-481. https://doi.org/10.2105/AJPH.2021.306601).