NEW YORK, June 30 (Reuters) -- Smokers with heart disease can safely use the nicotine patch to try to kick the habit, a new study suggests. What's more, patch-users rapidly show an improvement in the heart's function -- despite the fact that the amount of nicotine is greater in the blood with the patch than with cigarettes.
"We would have to conclude that even for patients with heart disease, receiving nicotine from patches is safer than receiving nicotine from cigarettes," reported Dr. Thomas Kottke, of the Mayo Clinic in Rochester, Minnesota. And heart disease patients are not limited solely to the patch. Any nicotine replacement system seems to be better than smoking cigarettes, including using nicotine gum or nasal spray, he wrote in an editorial in the current issue of the Journal of the American College of Cardiology.
Heart disease patients using the nicotine patch increased exercise duration by 10%, and reduced areas of the heart with ischemia -- reduced blood flow -- from 17% to 12%, according to the study of 36 heavy smokers (more than a pack a day for 40 years). This occurred even when nicotine levels nearly doubled, from 16 nanograms per milliliter (ng/ml) of blood to 24 to 30 ng/ml, and even though some patients continued to smoke a few cigarettes. The participant's heart function was monitored during exercise after using a 14 milligram patch for an average of nine days, and again after using a 24 milligram patch for an average of eight days.
"Nicotine does not appear to pose significant safety concerns for patients who are attempting to quit smoking," wrote lead study author Dr. John J. Mahmarian, of the Baylor College of Medicine in Houston, Texas. "This study further suggests that carbon monoxide and possibly other components of cigarette smoke, rather than nicotine, may actually be more critical for the development of myocardial ischemia."
The new study was funded with a grant from Hoechst Marion Roussel, Inc., the Kansas City, Missouri-based manufacturer of Nicoderm, a nicotine patch.
There are about 3 to 5 million smokers with heart disease in the U.S. Those who continue to smoke have twice the risk of dying as those who quit, and half the life expectancy if they continue to smoke after having a heart attack, Kottke noted.
"Nicotine replacement doubles the probability of a successful quit attempt in most trials," he wrote. Patients can also be taught how to resist cues to smoke, and positive support from family, friends, and co-workers can also help smokers kick the habit.
SOURCE: Journal of the American College of Cardiology (1997;30:125-132)
