The most effective prescription drug used to quit smoking initially helps women more than men, a recent study shows.
Varenicline, marketed as Chantix, was more effective earlier in women, and equally effective in women and men after one year.
“Studies show that women have a harder time quitting smoking than men, even as quitting has shown greater benefits to women’s cardiovascular and respiratory health,” says Sherry McKee, professor of psychiatry and lead researcher of Yale University’s Specialized Center of Research focused on gender and tobacco dependence. “With this first comprehensive analysis of sex differences in the effectiveness of this drug, now women and their healthcare providers can better decide how to successfully quit and live longer, healthier lives.”
McKee’s team found that varenicline was 46 percent more effective in women after three months of treatment, and 31 percent more effective at maintaining complete abstinence after six months.
Analyzing clinical trial data from 6,710 smokers using varenicline for smoking cessation through December 31, 2014, McKee’s team confirmed many prior clinical trial findings in demonstrating that women were less likely than men to quit when using a placebo.
Unlike nicotine replacement or bupropion (marketed as Wellbutrin and Zyban, among other brand names), which produce lower rates of quitting in women, varenicline produced similar rates of smoking abstinence for men and women—53 percent after three months, according to the researchers. But when factoring in the lower placebo effect in women, they found that varenicline increased the odds of women quitting by 46 percent.
“While it’s clear that sex differences in varenicline efficacy exist, we don’t yet know why varenicline is particularly effective for women,” McKee says, adding that sex differences in the nicotine receptor system in the brain may be a key factor.
“This is the first demonstration that women compared to men have a preferred therapeutic response for a smoking cessation medication when considering short-term treatment outcomes and equal outcomes at one year. Varenicline appears to be particularly useful for reducing the sex disparity in smoking cessation rates,” she adds.
Other researchers from Yale, Yeshiva University, and Brown University contributed to the study published in the journal Nicotine and Tobacco Research. The National Institutes of Health Office of Research on Women’s Health and the National Institute of Drug Abuse funded the work.
Source: Yale University