(Dobson et al., 1991; Gordon et al., 1974; Lightwood and Glantz, 1997), and others have suggested that some residual excess risk remains (Negri et al., 1994; Teo et al., 2006). Studies have reported a range of latency periods for such risk reduction, with the shortest being 2 or 3 years (Gordon et al., 1974). In addition, the 1990 report The Health Benefits of Smoking Cessation: A Report of the Surgeon General (HHS, 1990) and the National Cancer Institute’s Monograph 8: Changes in Cigarette-Related Disease Risks and Their Implications for Prevention and Control (NCI, 1997) discussed the cardiovascular benefits of smoking cessation. On the basis of a systematic review of 20 cohort studies, Critchley and Capewell (2003) estimated that there was a 36% reduction in mortality in patients with coronary heart disease who quit smoking compared with those who continued smoking. Their data provide evidence that limitation of secondhand-smoke exposure should reduce risk of mortality from coronary heart disease substantially.
The high prevalence of secondhand smoke and consequently the increased risk of coronary heart disease in the U.S. general population have important implications for public health. According to the Third National Health and Nutrition Examination Survey (NHANES III), about 43% of nonsmoking children and 37% of nonsmoking adults are exposed to secondhand smoke in the United States (Pirkle et al., 1996). The California Environmental Protection Agency has estimated that 46,000 (range, 22,700–69,600) excess cardiac deaths in the United States each year are attributable to secondhand-smoke exposure at home and in the workplace (Cal EPA, 2005b). Thus, home and workplace exposure can potentially produce a substantial burden of avoidable deaths from coronary heart disease. Similarly, Lightwood et al. (2009) recently estimated that at the 1999 to 2004 levels, passive smoking leads to 21,800 to 75,100 deaths from coronary heart disease and 38,100 to 128,900 myocardial infarctions annually.
Progress has been made recently in reducing involuntary exposure to secondhand smoke in workplaces, restaurants, and other public places in the United States and abroad. According to the surgeon general’s 2006 report (HHS, 2006), the percentage of U.S. nonsmokers 4 years old and older who are exposed to secondhand smoke decreased from 88% in 1988–1991 to 43% in 2001–2002, improving on the Healthy People 2010 target of 45% (HHS, 2000). Despite the improvement, some 126 million nonsmokers living in the United States in 2000 were still being exposed to secondhand smoke. Data reviewed in the surgeon general’s 2006 report indicate that smoke-free policies are the most economical and effective way to reduce secondhand-smoke exposure (HHS, 2006); the effect of legislation to ban smoking in public places and workplaces on cardiovascular health of nonsmoking adults, however, remains a question.