Socioeconomic inequalities in secondhand smoke exposure before, during and after implementation of Quebec’s 2015 ‘An Act to Bolster Tobacco Control’

Abstract

BackgroundTo better understand whether tobacco control policies are associated with changes in secondhand smoke (SHS) exposure across socioeconomic groups, we monitored differences in socioeconomic inequalities in SHS exposure in households and private vehicles among youth and adults before, during and after adoption of Quebec’s 2015 An Act to Bolster Tobacco Control.MethodsUsing data from the Canadian Community Health Survey, we examined the prevalence of daily exposure to SHS in households and private vehicles among youth (ages 12 to 17) and adults (ages 18+) across levels of household education and income (separately) in 2013/2014, 2015/2016 and 2017/2018. We tested differences in the magnitude of differences in outcomes over time across education and income categories using logistic models with interaction terms, controlling for age and sex.ResultsWe detected inequalities in SHS exposure outcomes at each time point, most markedly at home among youth (OR of SHS exposure among youth living in the 20% poorest households vs the 20% richest=4.9, 95% CI 2.7 to 6.2). There were decreases in SHS exposure in homes and cars in each education/income group over time. The magnitude of inequalities in SHS exposure in homes and cars, however, did not change during this period.ConclusionsThe persistence of socioeconomic inequalities in SHS exposure despite implementation of new tobacco control laws represents an increasingly worrisome public health challenge, particularly among youth. Policymakers should prioritise the reduction of socioeconomic inequalities in SHS exposure and consider the specific needs of socioeconomically disadvantaged populations in the design of future legislation.

Effect of smoke-free policies in outdoor areas and private places on children's tobacco smoke exposure and respiratory health: a systematic review and meta-analysis

“…From 204 full-text articles assessed for eligibility, 11 eligible studies were included in the qualitative synthesis (figure 1). 15,[25][26][27][28][29][30][31][32][33][34] No ongoing or unpublished studies were found.…”

“…30 Four of the 11 eligible studies did not meet EPOC criteria (figure 1). [31][32][33][34] Ten effect estimates from four studies evaluating the effects of smoke-free car policies on child TSE in cars could be meta-analysed given that they assessed the immediate effects of similar policies on the same outcome. 15,25,26,28 In the two-level meta-analysis of these estimates, smoke-free car policies were associated with an immediate risk reduction in child TSE in cars (RR 0•69, 95% CI 0•55-0•87; 161 466 participants; figure 2).…”

“…Another Canadian study showed that TSE at home was reduced following a comprehensive policy that included outdoor areas and cars. 34 Two studies found that the comprehensive, city-wide smoke-free policy in Hong Kong was associated with a reduction in TSE in areas that were not covered by the policy; 32,33 however, one study found the opposite. 31 This inconsistency could derive from the fact that the study by Ho and colleagues 31 was based on child reports, whereas the other two studies relied on parent-reported outcomes, which could be subject to increased desirability bias.…”

Justice, disparities and the tobacco endgame

“…Similarly, a Canadian study examining changes in secondhand smoke exposure before, during and after a 2015 population tobacco control measure that extended smoke-free laws found that among groups of different income and education levels, exposures among all groups decreased across time periods but the magnitude of inequalities in exposure did not change. 5 Given these persistent disparities, it is important to consider prioritising public health interventions that not only reduce smoking overall, but also contribute to reducing the disparities themselves. Smith et al 6 conducted a review on the equity impacts of population-level tobacco control interventions and found mixed results.…”

Protecting vulnerable groups from tobacco-related harm during and following the COVID-19 pandemic

“…For example, a study from Quebec found that SHS exposure in the home was nearly 5fold more common among youth in the lowest versus the highest income quin tiles. 29 Since public health orders to stay at home have likely increased the number of smokers who use tobacco indoors, it is probable that more individuals with low socioeconomic status have been and will continue to be exposed to SHS. Indoor smoking is especially concerning in multi unit housing, mostly populated by low income families, as smoke is carried in shared ventilation systems and therefore affects multiple dwellers.…”