LAUSR

OBJECTIVES This study aimed to examine socio-economic disparities in mother-child pairs' self-reported and cotinine-measured secondhand smoke (SHS) exposure at home. STUDY DESIGN This is a cross-sectional study. METHODS This study was conducted in the Rajshahi district of Bangladesh from May to July 2017. A total of 541 mother-child pairs were interviewed for self-reported measured SHS; cotinine-measured saliva test was performed on 263 mothers and 236 children. Mother-child pairs' SHS exposure at home was the outcome of interest. RESULTS Overall self-reported prevalence of SHS exposure at home was 49.0%. Self-reported SHS exposure among mothers (50.2%) and children (51.3%) were lower than the prevalence rate of cotinine-measured exposure for mothers (60.5%) and their children (58.9%). Maternal rich bands of wealth were found to be associated with lower likelihood of self-reported (adjusted odds ratio [AOR] = 0.59, 95% confidence interval [CI] = 0.35-0.99) and cotinine-measured SHS exposure among mothers (AOR = 0.17, 95% CI = 0.08-0.37). Maternal rich bands of wealth were also found to be associated with lower likelihood of cotinine-measured SHS exposure among children (AOR = 0.11, 95% CI = 0.07-0.26). CONCLUSIONS Socio-economic inequalities exist in exposure to SHS at home. Interventional approaches aimed at reducing SHS at home are urgently needed at public health and healthcare service level, with special focus given to the socioeconomically disadvantaged groups.