Effect of smoke-free legislation on the incidence of sudden circulatory arrest in the Netherlands
Authors: D de Korte-de Boer, D Kotz, W Viechtbauer, et al
Reference: Heart 2012;98:995-999 (open access) http://bit.ly/V2kwux
Reviewer: Joaquin Barnoya, MD, MPH
Reviewer comments: This is the first study to analyze the impact of a smoking ban on SCA. Most likely inadequate enforcement of the second smoking ban failed to lead to a further decrease in the incidence of SCA.
Purpose of the study: In the Netherlands, smoke-free legislation was implemented in two phases. A general workplace ban came into effect January 2004. In July 2008, catering sports and the hospitality sectors were also included in the ban. This study sought to assess the effect of the 2004 and 2008 smoking ban on the incidence of out-of-hospital sudden coronary arrest (SCA) in South Limburg.
Methods: The region of South Limburg in the Netherlands is served by a single, centrally coordinated, emergency medical service provider. Data on SCA incidence were obtained from the medical service registry. Every time an ambulance is dispatched, personnel complete a record containing information on age, gender, cause of injury, situation on arrival and medical care provided. All cases that fitted the definition of SCA were considered to be confident cardiac caused SCA cases. Three time periods were analyzed. The pre-ban (January 2002-January 2004) in which there was no smoking ban, the first post-ban period in which the first workplace ban came into effect (January 2004-July 2008), and the second post-ban period in which the hospitality sector was included (July 2008-May 2010). The main outcome variable was the weekly number of incident SCA cases. Confounding variables included ambient temperature, airborne particulate matter, and influenza rates.
Results: A total of 2305 SCA cases were observed, mean weekly incidence of 5.3 (range 0-14) cases. Most (72.8%) were confident SCA cases that received resuscitation and/or defibrillation. Mean age (SD) of cases was 59.9 (10.8) years. There was no indication of serial dependence in the SCA incidence nor did it show any seasonal patterns. In the adjusted model, the pre-ban period SCA incidence increased significantly by 0.20% cases per week. After the introduction of the fist ban the trend changed -0.24% cases per week (p=0.04), translating into a 6.8% (22 cases) reduction in the number of cases after 1 year of the ban. No additional decrease was seen after the second ban.