It has been well-documented in clinical studies that smoking cessation after patients undergo PCI can improve outcomes. Some research has identified certain predictors of smoking cessation after PCI, including previous cigarette consumption and the number of coexisting coronary artery disease risk factors. Few studies, however, have assessed current trends in smoking cessation after PCI and looked at the potential impact of smoke-free policies that are being enacted throughout many parts of the United States. “Historically, patients who undergo PCI are a group that has more difficulty quitting smoking than others,” says Randal J. Thomas, MD, MS.
The Effect of Smoke-Free Policies
In a study published in the February 15, 2015 issue of the American Journal of Cardiology, Dr. Thomas and colleagues assessed trends and predictors of smoking cessation after PCI in Olmsted County, Minnesota. The investigators conducted the research at a time when local and statewide smoke-free public policies were enacted in Olmsted County. The study followed 2,306 patients who underwent their first PCI from 1999 to 2009 for 12 months. The researchers conducted structured telephone surveys at 6 and 12 months after PCI to assess smoking status and quit rates during the 10-year period.
The authors paid particular attention to quite rates around two dates when three smoke-free ordinances were implemented to reduce secondhand tobacco exposure in Olmsted County. The first date was January 1, 2002, when an ordinance was passed requiring restaurants to be smoke-free. The second was October 1, 2007, when ordinances required both workplaces and the entire state of Minnesota to be smoke-free. The data were then analyzed according to three time periods: 1991 to 2001, 2002 to 2006, and 2007 to 2009.
According to the results, there was a small but non-significant decrease in overall smoking rates among PCI recipients in Rochester, Olmstead County, and across the state of Minnesota. However, the percentage of current smokers among PCI patients was still higher than the percentage noted in the general population of these regional domains throughout the study period. Men were typically more likely to be smokers at the time of PCI than women (Figure 1), but this trend reversed in 2001 when 28% of women and 17% of men were smokers at the time of PCI.
The overall prevalence of smoking in patients who underwent PCI increased non-significantly from 20% in 1999 to 2001 to 24% in 2007 to 2009. When assessed at both 6 and 12 months, smoking cessation rates after PCI changed very little after analyzing data from 1999 to 2001 and 2007 to 2009 (Figure 2). “Our data are troubling because smoking cessation rates did not change significantly over the 10-year period,” says Dr. Thomas. “This occurred even though our analysis took into account time periods in which smoke-free policies were enacted.”
Examining Possible Reasons
Dr. Thomas says there are several possible explanations for the findings his study team observed. “Many smokers who undergo PCI are very unlikely to quit, even with the help of smoking cessation programs and the enactment of smoke-free ordinances,” he says. In addition, the study noted that smoking cessation therapies prescribed in the hospital setting after PCI may be underdosed or underused. Furthermore, follow-up after smoking cessation treatment may be lacking in outpatient settings.
Previous research that has examined the effect of community-wide smoke-free regulations and some studies suggest that these efforts help to reduce acute cardiac events. However, findings of the study by Dr. Thomas and colleagues suggest that similar improvements may not occur among PCI recipients. Overall, smoking rates have decreased among the general population over the past three decades, but this decrease does not appear to translate to improved smoking cessation rates in patients undergoing PCI.
Importantly, the study identified several strong predictors of smoking cessation at 6 months after PCI. These included participation in cardiac rehabilitation, older age, and concurrent myocardial infarction at the time of PCI. “In our study, participating in cardiac rehabilitation was associated with significantly higher quit rates,” says Dr. Thomas. “This was probably due to a number of factors, including the benefits of individualized case management services that are provided through cardiac rehabilitation programs. This finding highlights the fact that these patients need more attentive care and monitoring. We need to improve the delivery of systematic services that promote smoking cessation. In the future, greater use of cardiac rehabilitation should be part of our efforts to improve smoking cessation rates after PCI.”
Sochor O, Lennon RJ, Rodriguez-Escudero JP, et al. Trends and predictors of smoking cessation after percutaneous coronary intervention (from Olmsted County, Minnesota, 1999 to 2010). Am J Cardiol. 2015;115:405-410. Available at: http://www.sciencedirect.com/science/article/pii/S0002914914021614.
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