Smoking is not a predictor of mortality and morbidity following coronary artery bypass grafting

The objective of this study was to determine the significant differences in preoperative and operative characteristics, and postoperative outcomes in patients having coronary artery bypass grafting (CABG) who are smokers and in those who are not smokers.

Data were collected prospectively in all (2916) patients having their first CABG. The patients were cared for in a regional medical center by private physicians. No operations were denied because of smoking status. Smokers differed from nonsmokers in several characteristics.

Analysis of morbidity and mortality showed no instance in which smokers fared worse than nonsmokers. Stepwise logistic regression analysis showed that smoking was not predictive of mortality. Smoking was not predictive of morbidity except that it was predictive of less probability of need for intra-aortic balloon pump (7.5% in nonsmokers and 4.7% in smokers). We then created groups of smokers and nonsmokers that were individually matched for age and sex. Analysis of the matched groups of smokers and nonsmokers showed that there was no significant difference in the incidence or magnitude of preoperative and operative factors except that recent myocardial infarction was more common in smokers. Nonsmokers had greater weight, body mass index (obesity), and ejection fraction. There was no difference in smokers and nonsmokers in mortality or morbidity at the 99% confidence level.

We conclude that there is no need to delay CABG for the patients who are smokers.