The effect of the smoke-free law in Spain on quit ratio and inequalities in smoking cessation: an observational study

Abstract

BackgroundSmoke-free policies have reduced the exposure to environmental tobacco. Smoke-free policies might also have important side-effects on smokers' behaviour, inducing them to either quit altogether or reduce the number of cigarettes smoked. Population-level interventions might increase smoking inequalities. However, very few studies have assessed the effect of nationwide smoke-free policies by socioeconomic status. Socioeconomic differences in quitting smoking after the implementation of the smoke-free policy remained unchanged in England, but they were reduced in Scotland. However, in Italy educational differences in quit ratios widened over time after the implementation of a smoke-free policy. On Jan 1, 2006, Spain introduced a comprehensive smoke-free law covering workplaces, bars, and restaurants. The objective of this study was to assess whether Spain's smoke-free legislation provide a strong incentive to quit smoking and to investigate whether the possible changes associated with the ban differ according to social class. MethodsNational health surveys were undertaken in Spain between 2001 and 2011. About 21 000 adults aged 16 years or older were interviewed in each survey. With regard to smoking, participants were classified as never smokers, former smokers, or present smokers. The smoking cessation (quit ratio) was defined as the proportion of ever smokers who were former smokers. The measure of socioeconomic position used was the head-of-household occupational social class—the one who provided the most income to the household. Socioeconomic position was grouped in manual and non-manual workers. The analysis was restricted to men and women aged 25–64 years. In each year and in both social classes age-adjusted quit ratios were estimated. Then the quit ratio rate was calculated in non-manual versus manual social classes. FindingsBetween 2001 and 2006, the quit ratio increased in both social classes in men and women, but between 2006 and 2011 the quit ratio hardly changed in men and decreased in women. In men, the quit ratios in 2001, 2006, and 2011 were 29·3% (95% CI 26·3–32·3), 36·7% (34·1–39·2), and 36·5% (33·0–39·9), respectively, in the manual social class and 36·4% (32·5–40·2), 42·5% (39·6–45·3), and 43·5% (40·4–46·7), respectively, in the non-manual social class. In women, the quit ratios in 2001, 2006, and 2011 were 27·5% (95% CI 22·4–32·7), 33·0% (29·4–36·5), and 29·9% (25·7–34·1), respectively, in the manual social class and 31·6% (26·5–36·8), 43·0% (39·3–46·7), and 41·7% (38·0–45·3), respectively, in the non-manual social class. The quit ratio rate in non-manual versus manual social classes was 1·16 in 2006 and 1·19 in 2011 in men and 1·31 in 2006 and 1·39 in 2011 in women (appendix). InterpretationIn Spain, smoke-free legislation interrupted the upward trend in quit ratio reported in manual and non-manual social classes in the previous years. This effect was slightly lower in the non-manual social class and therefore inequalities in quit ratio increased. Although a possible effect of the economic crisis since 2008 cannot be excluded, these results were noted in Italy after the implementation of the smoke-free policy in 2005 and support other studies in Spain showing that the downward trend in smoking prevalence rapidly reversed after the implementation of the law in 2006. The findings suggest a different response in northern countries, such as Scotland or England, compared with southern European countries after the implementation of smoke-free legislation. FundingThis work was undertaken by the project “Tackling socioeconomic inequalities in smoking: learning from natural experiments by time trend analyses and cross-national comparison (SILNE)”, funded by the European Union.