NEW ORLEANS — Patients who quit smoking within a year after coronary artery bypass graft surgery prolong their life expectancy by an average of 3 years, Dr. Don Poldermans said at the annual meeting of the American College of Cardiology.
“This [information] is a practical tool for physicians to use. … It may be the ultimate reason for the patient to quit smoking,” observed Dr. Poldermans of Erasmus University, Rotterdam, the Netherlands.
It's well accepted that smoking cessation after coronary revascularization or MI reduces mortality risk. Dr. Poldermans presented the first study to quantify this benefit in years of life saved.
He reported on 30-year outcomes for 1,041 consecutive patients who underwent venous CABG at the medical center in 1971–1980. A total of 551 were smokers at the time, of whom 43% quit within a year.
The 10-year survival was 88% in those who quit, compared with 77% in the persistent smokers. Survival at 15 and 30 years was 70% and 19%, respectively, in the patients who had quit smoking, compared with 53% and 11% in those who did not.
The average life expectancy was 20 years for patients who quit smoking and 17 years for persistent smokers.
Smokers younger than 50 years at the time of CABG who quit smoking within the next year lived an average of 3.5 years longer than did those who kept smoking. Patients aged 50–60 years at surgery and who ceased smoking gained an average of 2.8 years, compared with persistent smokers. Those who quit following CABG after age 60 had a 1.7-year greater life expectancy than did those who didn't quit.
Dr. Poldermans said that these are conservative estimates of the life expectancy benefit of smoking cessation because they derive from the early era of CABG. In the early 1970s, CABG was largely reserved for relatively young, otherwise healthy patients of a sort that cardiac surgeons seldom encounter today. Today's CABG patients are much sicker, older, and higher risk—and the greater a patient's risk, the greater the benefit of an effective intervention.
After adjustment for potential confounders, smoking cessation remained an independent predictor of lower mortality, conferring a 38% relative risk reduction.