Reduction in passive smoking exposure probably the main reason say researchers
Sophia Antipolis, France, 3 Oct. 2006:
Hospital admissions for acute heart attack in people under 60 fell by 11% in the Piedmont region of Italy in the five months after the introduction of a ban on smoking in indoor public places compared with admissions for the same period in the previous year.
Importantly, nearly all of the fall was probably due to reductions in exposure to passive smoking, the researchers, from the University of Turin, concluded.
Their results, published in the latest on line edition of European Heart Journal (1), today (Tuesday, 3 October) add more evidence to studies supporting the effectiveness of smoking regulations, according to the authors of an accompanying editorial (2).
“The argument of the ‘victimless crime’ clearly and finally has to leave the discussion based on accumulating data, including this new research,” said editorial co-author Dr Peter Radke, consultant cardiologist at Department of Cardiology and Angiology at the University Hospital of Schleswig-Holstein in Lübeck, Germany.
The Italian Government banned smoking in all indoor public places on 10 January 2005. The researchers, led by Dr Francesco Barone-Adesi, analysed all hospital admissions with discharge diagnoses of acute myocardial infarction (AMI), and AMI deaths, between January 2001 and June 2005 for residents throughout the region of Piedmont (population 4.3 million).
“From February 2005 to June 2005, the immediate period following the ban, we found a significant drop in admissions for AMI among both men and women under the age of 60, with 832 cases compared to 922 for the same months in the previous year. Moreover, the rates of AMI had, if anything, been increasing between 2001 and 2004, so the reduction we saw in the first half of 2005 was not attributable to long-term trends. In fact, as there was evidence that AMI was increasing over time, it’s possible that our estimate of an 11% decrease after the introduction of the ban is even an underestimate,” said Dr Barone-Adesi, who is a cancer researcher at the Cancer Epidemiology Unit at the University of Turin.
He said that both active and passive smoking contributed to the fall, but that only around 1% was likely to be due to active smoking, a conclusion reached after studying the effects of the ban on the habits of active smokers. “We found that the observed reduction in active smoking after the ban could account for only a 0.7% decrease in admissions and that about a 10% decrease is due to the sharp reduction of exposure to passive smoking.”
The decrease in admissions was confined to under 60s. Dr Barone-Adesi said several studies had found that the relative risk and attributable risk of AMI for smoking decreases with age. The reason was still a matter of debate, but a probable explanation was that other risk factors become more important as people age. It was also the case that younger people tend to spend more time in public places exposed to smoke, so a different effect was not unexpected.
He said that smoking acts on the aggregation of platelets in the blood and was most likely to increase acutely the risk of AMI. “This may explain our finding of an 11% decrease in the first five months after the ban began. It suggests that smoking regulations may have important short-term effects on health. The long-term effects on respiratory and cardiovascular diseases and cancer will have to be evaluated over the years to come.”
Co-author of the editorial, Professor Heribert Schunkert, Director of the Department of Cardiology and Angiology at University Hospital of Schleswig-Holstein, said that Dr Barone-Adesi and his team provided further evidence from national registries and surveys – an 8.9% fall in cigarette sales, 7.6% reduction in cigarette consumption and a more than 90% reduction in nicotine vapour phase concentration in pubs and discos – suggesting that the smoking ban in Italy did reduce overall smoking, which was likely leading to the observed effect on AMI admissions.
“The implications of the study for public measures of health are important. While there are some limitations to the Barone-Adesi study, in our view these findings are an important addition to the growing body of research indicating that tightening the regulations on public smoking will play a vital role in improving public health and reducing deaths from smoking.”
Dr Radke said that in October 2000 South Africa was the first country in the world to ban smoking in public areas and some US states and cities instituted smoking-free regulations before the European Union. Ireland was the first northern hemisphere country to ban smoking in enclosed places from March 2004 and has become the leading model for Europe. Norway, Sweden, Italy and Scotland have instituted countrywide legislation and more EU countries are due to follow suit.
“It took quite a long time to implement smoking-free policies in the ‘old world’, but Europe is on the move,” he concluded.
1 Short-term effects of Italian smoking regulation on rates of hospital admission for acute myocardial infarction. European Heart Journal. doi:10.1093/eurheartj/ehl201.
2 Public smoking ban: Europe on the move. European Heart Journal.
A PDF of the full reports are available on request or is available on: