August 28, 2010 - It's never too late for smokers to do their hearts good by kicking the habit -- even after a heart attack has left them with significant damage to the organ's main pumping chamber, a new study suggests. Past studies have found that smokers who kick the habit after suffering a heart attack have a lower rate of repeat heart attacks and live longer than their counterparts who continue to smoke.
But little has been known about the benefits of quitting among heart attack patients left with a complication called left ventricular (LV) dysfunction -- where damage to the heart's main pumping chamber significantly reduces its blood-pumping efficiency.
So it has been unclear whether that dysfunction might "drown out" the heart benefits of smoking cessation, said Dr. Amil M. Shah, the lead researcher on the new study and a staff cardiologist at Brigham and Women's Hospital in Boston.
PAPER: Risk of All-Cause Mortality, Recurrent Myocardial Infarction, and Heart Failure Hospitalization Associated With Smoking Status Following Myocardial Infarction With Left Ventricular Dysfunction, Amil M. Shah, MD et al., American Journal of Cardiology published online 13 August 2010, ABSTRACT..
Shah and his colleagues found that heart attack survivors with LV dysfunction may stand to benefit as much from smoking cessation as other heart attack patients do.
The researchers found that among 2,231 patients with LV dysfunction, those who quit smoking within six months of their heart attack were less likely to die within five years or suffer a repeat attack than smokers who continued the habit.
Of all patients, 463 were smokers at the time of the heart attack but had quit six months later; 268 were still smoking at the six-month mark. Among quitters, 15 percent died or suffered another heart attack by the end of the study, which followed the patients for up to five years. That compared with a rate of 23 percent among patients who were still smoking six months after their initial heart attack.
When Shah's team accounted for a number of other factors -- including age, medical history and body weight -- smoking cessation itself was linked to a 40 percent reduction in the risk of death compared with persistent smoking.
Quitters were about 30 percent less likely to die, suffer a repeat heart attack or be hospitalized for heart failure during the study period.
"The findings aren't completely surprising," Shah told Reuters Health. But, he said, they offer reassurance to patients with LV dysfunction that they can benefit from smoking cessation -- and the magnitude of that benefit is similar to what has been seen among heart attack survivors without LV dysfunction. "I've had patients who say, 'What's the point of quitting now?'" Shah noted. "But it's never too late to benefit from smoking cessation."
Some studies have found that smoking-cessation counseling begun in the hospital, and continued after discharge, may be particularly effective for heart attack patients.
Patients at hospitals that do not offer such counseling should speak with their cardiologist or primary care doctor about smoking cessation, Shah advised.
Why Quit Smoking?:
* After one year off cigarettes, the excess risk of coronary heart disease caused by smoking is reduced by half. After 15 years of abstinence, the risk is similar to that for people who've never smoked.†
* In 5 to 15 years, the risk of stroke for ex-smokers returns to the level of those who've never smoked.†
* Male smokers who quit between ages 35 to 39 add an average of 5 years to their lives. Female quitters in this age group add 3 years. Men and women who quit at ages 65 to 69 increase their life expectancy by 1 year.‡
Smoking Cessation, American Heart Association (AHA)..
Reference: Quitting smoking helps after serious heart attack damage by Amy Norton, Reuters, 8/26/2010.