Drug Helps Smokers Quit and Lose Weight
药物帮助抽烟者戒烟和减肥
For all those smokers who want to quit but haven´t because they´re afraid of packing on the pounds, researchers have exciting news.
A new drug called rimonabant helped smokers kick the habit and even lose a little weight in the process, according to a presentation made this week at the American College of Cardiology´s annual meeting in New Orleans.
"It is early, but our findings are very promising," says co-researcher Dr. Lowell Dale, associate director of the Mayo Clinic Nicotine Dependence Center in Rochester, Minn. "This medication really appears to have the potential to assist in stopping smoking and controlling weight while stopping, which could significantly reduce the risk of cardiovascular disease."
The findings were announced just before a study in the March 10 issue of the Journal of the American Medical Association reported that smoking, obesity and a sedentary lifestyle are responsible for more than 800,000 deaths in the United States every year. Tobacco, according to the report, is the biggest killer, causing 435,000 deaths.
"To have a drug which could get to two of the major lifestyle problems associated with heart and vascular disease would just be incredible," says cardiologist Dr. Stephen Siegel of New York University Medical Center.
Dr. LaMar McGinnis, a senior medical consultant with the American Cancer Society, agrees. "If this drug does have minimal side effects and consequences, then the benefits could be enormous."
"We are excited about the potential for this, but we are in a wait-and-see mode," he adds, noting that more research, particularly long-term studies, needs to be done.
The current study followed 787 smokers who were "motivated" to stop smoking, according to Dale. They´d been smoking for 11 to 24 years and averaged 23 cigarettes a day.
One-third of the group was given a placebo, another third received 5 milligrams daily of rimonabant, and the final third received 20 milligrams of rimonabant once a day.
Treatment started two weeks prior to the volunteers´ quit day, and continued for eight weeks. The participants couldn´t use any additional measures to stop smoking—such as nicotine replacement, antidepressants or behavioral therapy—during the clinical trial and in the three months leading up to the trial.
Almost 28 percent of those taking 20 milligrams of rimonabant were able to stop smoking during the study period. By comparison, only 15.6 percent of those taking the low dose of rimonabant were successful in their quit attempt, and 16.1 percent of those taking a placebo stopped smoking.
What´s more, those on the high dose of rimonabant managed to lose slightly more than haft a pound during the study period, while those given a placebo gained 2.5 pounds.
Side effects appeared to be minimal. The most common, according to Dale, was nausea.
Rimonabant is the first in a new class of drugs that target the Endo Cannabinoid system, which
is located in the brain and other areas of the body. Dale says this system is stimulated by nicotine
and possibly by overeating. When it´s stimulated, dopamine—a neurotransmitter—is released, causing feelings of pleasure, which reinforces the behavior, he says.
"This drug blocks this system, so that when people eat or smoke, they don´t get the same response, which tends to decrease the behavior," Dale explains.
He says there are two more clinical trials in progress, and a year-long trial to assess the long-term effects of the medication is planned. He says he believes the manufacturer of rimonabant will likely begin the US Food and Drug Administration approval process by the end of this year or early next year.
At the same conference, Canadian researchers reported on a trial of more than 1,000 people with body mass indexes (BMIs) over 27. A BMI above 24 is considered overweight. Those who took 20 milligrams daily of rimonabant lost an average of 20 pounds and more than three inches off their waist circumference. They also lowered their cholesterol levels by 25 percent and their triglyceride levels by 15 percent, the study found.
Siegel says his big concern about rimonabant is that you may need to stay on it indefinitely, particularly if you´re taking it for overeating.
"The long and short of it is that this drug is extremely enticing and thought-provoking in therms of the actual drug, and in terms of how some of our dependencies develop," says Siegel.