Abstract 16722: Myocardial Infarction and Sudden Cardiac Death in Olmsted County, Minnesota, Before and After Smoke-Free Workplace Laws

Abstract

Objective: To determine if the implementation of smoke-free workplace laws reduced the incidence of the acute coronary events including myocardial infarction (MI) and sudden cardiac death (SCD). Background: Nonsmokers chronically exposed to second-hand smoke (SHS) are at increased risk of death from heart disease. However, a nonlinear dose relationship exists between SHS exposure and coronary heart disease (CHD) such that the relative risk of CHD is 1.31 for nonsmokers and 1.78 for smokers. Reductions in admissions for MI in locales where smoke-free workplace laws have been implemented have been observed, but none have assessed SCD. On January 1, 2002, a smoke-free restaurant law (Ordinance #1) was implemented in Olmsted County, Minnesota, and on October 1, 2007, all workplaces became smoke-free (Ordinance #2). Methods: Under the auspices of the Rochester Epidemiology Project, we measured the incidence of MI and SCD during the 18-month calendar period before and after implementation of each smoke-free ordinance. All MI were validated using biomarkers, cardiac pain, and Minnesota coding of the ECG. SCD was defined as out-of-hospital deaths assigned to CHD (ICD-9 codes 410 through 414). Results: For the overall study period of the 18 months before the implementation of the smoke-free restaurant ordinance and 18 months after the implementation of the smoke-free workplace ordinance, we observed a 45% decline in the incidence for MI (p <0.01) and a 50% decline in the incidence for SCD (p <0.01). See Table. During this same period, the prevalence of hypertension, diabetes, hypercholesterolemia, and obesity either remained constant or increased while the prevalence of smoking among adults declined by 23% (22% to 17%). Conclusion: In the Olmsted County population, substantial declines in the incidence of MI and SCD were observed after smoke-free laws were implemented. Smoke-free workplace laws may not only be associated with a decrease in MI but SCD as well.