Objective Many studies demonstrated a decline in hospital admissions for cardiovascular diseases after the implementation of a smoking ban, but evidence for reductions in cardiovascular mortality is more limited. In Belgium, smoke-free legislation was implemented in different phases. Public places and most workplaces became smoke-free in January 2006, whereas the legislative ban on smoking in restaurants was introduced in January 2007. These successive steps in legislation provided us the opportunity to investigate possible stepwise changes in fatal acute myocardial infarction (AMI) rates.

Methods Data on all AMI deaths of 30 years of age or older in Flanders (Belgium) between 2000 and 2009 (n=38 992) were used. Age-standardised AMI death rates were analysed with segmented Poisson regression allowing for secular trends, seasonality, temperature, PM₁₀ and influenza.

Results An immediate decrease in AMI mortality rates was observed in January 2006 (smoking ban at work). The effect was highest for women younger than 60 years of age (−33.8%; 95% CI −49.6 to −13.0), compared with an effect of −13.1% (95% CI −24.3 to −0.3) for male counterparts. Estimates for the elderly (≥60 years) were −9.0% (95% CI −14.1 to −3.7) for men and 7.9% (95% CI −13.5 to −2.0) for women. An additional effect of the smoking ban in restaurants was observed for elderly men, with an annual slope change of −3.8% (95% CI −6.5 to −1.0) after 1 January 2007.

Conclusions Smoking ban interventions are associated with reductions in the population rate of myocardial mortality, with public health gains even before and during the middle-aged period of life.