National smoking bans have been successful in reducing passive smoking-related harm, including heart disease, major new Irish research has shown.

Ireland became the first country in the world to ban indoor smoking in all public places in 2004. Since then, a number of other countries, regions and states have followed suit, banning smoking in public places and work places.

The main reason for these bans was to protect the health of non-smokers who were being exposed to passive (secondhand) smoke. But did this actually happen?

Irish researchers decided to investigate this further. A review of regions with smoking bans was first published in 2010 and the Irish team decided to update this review. They analysed 77 studies from 21 countries worldwide, including the UK, Spain and the US.

While the previous review had looked at how these new smoking laws had reduced smoking in public places, these latest studies assessed in detail the effects of passive smoking and associated health risks.

A total of 44 studies specifically focused on cardiovascular disease and the researchers found that 33 of these studies showed that heart disease rates fell significantly following the introduction of smoking bans.

Furthermore, the biggest reduction in hospital admissions for heart disease after the introduction of smoking bans was among non-smokers.

"The current evidence provides more robust support for the previous conclusions that the introduction of national legislative smoking bans does lead to improved health outcomes through a reduction in secondhand smoke exposure for countries and their populations," commented the review's author, Prof Cecily Kelleher, of University College Dublin.

She said that more research is now needed on the ‘continued longer-term impact of smoking bans on the health outcomes of specific sub-groups of the population, such as young children, disadvantaged and minority groups'.

Details of these findings are published in the Cochrane Database of Systematic Reviews 2016.