October 1, 2014BMC Cardiovascular Disorders32 citationsOpen Access
Smoking status and survival: impact on mortality of continuing to smoke one year after the angiographic diagnosis of coronary artery disease, a prospective cohort study
Key Result
Continuing to smoke at one year after revascularization for coronary artery disease was associated with a significantly lower long-term survival rate (88.9%) compared to quitting smoking (94.9%).
Study Design
Type
Cohort (n=11,334)
Multicenter
Yes
Structured PICO
Does quitting smoking at one year improve long-term survival in patients with coronary artery disease treated with medical therapy or revascularization?
P
Population
11,334 patients with angiographically diagnosed coronary artery disease who completed a one-year follow-up questionnaire, followed for a mean of 42.2 months.
E
Exposure
Smoking cessation at one year following angiography, and revascularization treatment strategy (CABG or PCI)
C
Comparator
Continuing to smoke at one year, and medical therapy alone
O
Outcome
Long-term survival (mortality) at mean 42.2 months follow-uphard clinical
Quitting smoking one year after angiographic diagnosis of CAD is associated with improved long-term survival, particularly in patients undergoing revascularization.
Main Result
Absolute Event Rate: 88.9% vs 94.9%
p-value: p=<0.05
Limitations
- Observational registry data subject to unmeasured confounding
- Self-reported smoking cessation rates without biochemical validation
- Lack of data on duration of smoking history or lifetime exposure to tobacco
- Surveys were not sent to families of subjects who died within one year, introducing potential survival bias
- Observational registry design with potential unmeasured confounding
- Reliance on self-reported smoking cessation rates
- Unknown duration of smoking history or lifetime exposure to tobacco
Abstract
BACKGROUND: Smoking is an undertreated risk factor for coronary artery disease (CAD) and is associated with adverse outcomes after myocardial infarction. Aims of our study were to determine if management of CAD by medical therapy (MT) alone or with coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) influence smoking status at one year following angiography and if a change in smoking status at one year influences long term survival. METHODS: Prospective cohort study using the APPROACH registry. Two cohorts were examined: (1) 11,334 patients who returned a one year follow-up questionnaire; (2) 4,246 patients propensity-matched based on their post-angiography treatment - MT or revascularization (RV). Multivariate modeling and survival analysis were used. RESULTS: In the propensity-matched cohort, quit rates at one year were greater among CABG patients (68%) than PCI (37%) or MT patients (47%). Smokers in the RV group, who self-reported quitting at one year, had a significantly reduced mortality compared to those who continued to smoke. CONCLUSIONS: CABG patients were more likely to quit smoking than those treated with MT alone or PCI. Quitting smoking was associated with improved long-term survival; smoking remains a key risk factor for mortality in patients with CAD. These data underscore the importance of nicotine addiction management in patients with CAD and the need to emphasize cessation particularly in those patients undergoing MT or PCI.