Reduction incidence of myocardial infarction associated with a national legislative ban on smoking

Abstract

Aim: The aim of the present study was to assess change in admissions for acute myocardial infarction (AMI) in the period immediately subsequent to the coming into force of law no. 3/2003 ''Protection of the health of non-smokers''.

Methods: Four Italian regions (Piedmont, Friuli Venezia Giulia, Lazio and Campania) took part in the study. Data regarding admissions for AMI were taken from the daily discharge papers of patients aged between 40 and 64 (cod. ICD9-CM 410.), in the period 10 January-10 March 2001-2005. Repeated admissions were excluded. Admission rates standardised by age and overall total, and specifically by region, age and gender were calculated. The hypothesis of a significant reduction between 2005 and 2004 was also checked.

Results: The results showed a decrease in the number of cases and in the standardised rates between 2004 and 2005. The number of admissions estimated with a linear regression model for 2005 was significantly higher than that really observed (+13%). The decrease between the 2005 and 2004 rates was noteworthy for all four regions. Analysis by gender shows that the effect is observed only in male patients and in the age classes 45-49 and 50-54.

Conclusion: This study shows that there has been an appreciable reduction in the incidence of heart attacks in the period immediately subsequent to the coming into force of the non-smoking Law in the populations surveyed, and that this reduction mainly regards men of working age. The reduction reverses a trend that has been evident for a number of years, namely that of a decidedly upward trend in the number of admissions for AMI.