CHICAGO—The continuation of smoking following a heart attack is the most powerful predictor for recurrent cardiac events among survivors age 35 years or younger, according to research presented by Loukianos Rallidis, MD, on Saturday at the 2008 American College of Cardiology (ACC) Scientific Sessions.
Rallidis, lead study investigator, said that patients who continue to smoke have approximately three times the risk for future heart problems (cardiac death, repeat MI or revascularization due to clinical deterioration), compared to those who quit smoking after the first acute MI (AMI). The higher risk was independent of the type of treatment, presence of other cardiovascular risk factors and even the function of the left ventricle (ejection fraction).
“This study suggests that smoking plays a major role not only in the development of AMI, but also in future coronary events,” said Rallidis of the University General Hospital Attikon in Haidari, Greece. “Patients who have suffered a heart attack very early in life can significantly improve their long-term prognosis by quitting smoking and adopting a healthier lifestyle, in addition to following the treatment plan set forth by their cardiologist.”
Of the 135 subjects in the study, Rallidis and colleagues found that more than half (56 percent) continued smoking after an MI event, and one out of three patients developed a cardiac event during this time period (three deaths, 30 acute coronary syndromes, and 11 revascularizations).
Almost half (45 percent) of the persistent smokers, who averaged 20 cigarettes per day, suffered from cardiac events, while only 18 percent of those who quit suffered an event during the follow-up period, according to Rallidis.
He reported that the patients were recruited between 1997 and 2001 from two large hospitals in Athens, Greece, and followed for up to 10 years. Three out of four patients were overweight or obese when they had their first heart attack; high cholesterol was the second most prevalent risk factor (behind smoking), and among the patients (70 percent had cholesterol levels above 200 mg/dl).
“It is imperative for the health system to provide effective smoking cessation programs as part of the holistic treatment of coronary heart disease,” said Rallidis. “Smoking is a modifiable risk factor and its effect is largely reversible.”
According to Rallidis, there has been a progressive increase in the number of young people suffering AMI, which is partially due to unhealthy dietary habits, lack of routine physical exercise and a high proportion of smoking among young people.
A previous study by Rallidis’s group found that the majority of patients (95 percent) experiencing a heart attack before the age of 36 years were smokers, which translated to a six-fold increased risk of AMI before 36 years of age compared to non-smokers, regardless of high cholesterol, high blood pressure or diabetes mellitus.
Rallidis stressed that this study should warn young patients who continue to smoke after suffering a heart attack that they are more likely to suffer from future cardiac problems.