Heart Benefits Trump Weight Gain in Smoking Cessation

Marlene Busko

March 13, 2013

LAUSANNE, SWITZERLAND — Middle-aged or older people who managed to stop smoking were about half as likely as smokers of the same sex and age to have a subsequent cardiovascular event--even though they tended to initially gain weight, in a new study [1].

Diabetic study participants who had recently quit smoking gained a median of 8 lbs in four years, and those without diabetes gained a median of 6 lbs in four years, but participants who had quit a long time ago did not continue to gain weight.

The study, based on Framingham data, is published in the March 12, 2013 issue of the Journal of the American Medical Association.

"This is the first study that demonstrated that weight gain after smoking cessation does not offset the benefits of quitting on CVD," lead author Dr Carole Clair (University of Lausanne, Switzerland) told heartwire in an email. "Cardiologists and clinicians must continue to advise their smoking patients to quit and can now reassure them that even if weight gain occurs, the [heart benefits from smoking] cessation . . . won't be diminished," she added.

Until now, the impact of smoking-cessation-related weight gain on CVD risk, especially in individuals with diabetes, was unknown, the authors write. To investigate this, they analyzed data from 3251 participants in the Framingham Offspring Study, from 1984 to 2011.

At baseline, the participants, an equal mix of men and women, had a mean age of 47.8 and no cardiovascular disease. About 11% had type 2 diabetes.

The researchers also examined data at four time intervals of six-year periods. The primary study outcome was the incidence of CVD events (a composite of CHD, cerebrovascular events, peripheral artery disease, and congestive heart failure) during six years.

The participants were classed as smokers, recent quitters (four or fewer years ago), long-term quitters (more than four years ago), or nonsmokers.

After a mean follow-up of 25 years, 631 CVD events occurred. Smoking prevalence decreased from 31% to 13%.

"We were expecting bigger weight gain among diabetics and were surprised that they did not gain that much, on average," said Clair. The study was not powered to probe outcomes in the participants who gained the most weight.

After adjustment for CVD risk factors, among participants withoutdiabetes, compared with smokers, those who quit smoking recently had a hazard ratio (HR) for CVD of 0.47 (95% CI 0.23–0.94), which was similar to the HR for CVD of 0.46 (95% CI, 0.34–0.63) for those who had quit long ago. The associations remained similar after further adjustment for weight change.

Participants with diabetes who had quit smoking had a similar trend to a decreased risk of CVD, although this was not significant. "We believe that [individuals with diabetes] benefit the same if not more from smoking cessation compared with nondiabetics; the fact that the results were nonsignificant is probably due to the smaller sample size," Clair said.

Quitting smoking was also linked with a decreased risk of MI or coronary death compared with smokers, and this association remained after adjustment for weight gain.

Encourage Every Smoker to Quit

In an accompanying editorial [2], Drs Michael C Fiore and Dr Timothy B Baker (University of Wisconsin School of Medicine and Public Health, Madison) write that "quitting smoking is arguably the most important step that smokers can take to improve their health and prevent premature death." However, about half of female patients and a quarter of male patients dread gaining weight if they stop smoking.

First, physicians should use the information from this study "to reassure patients concerned about the health effects of cessation-related weight gain . . . [and, second, they should] reinforce their commitment to provide or arrange evidence-based treatment for all of their patients who smoke," they write.

"The most important message of [this article] is that every smoker should be encouraged to quit smoking and given support to do so," they conclude.

"Don't Worry About a Bit of Weight Gain"

Asked to comment, Dr David Frid (Cleveland Clinic, OH) who was not involved in the study, said, "The ultimate take-away [is that] patients shouldn't worry about the little bit of weight they gain when they stop smoking, because the cardiovascular benefits are outweighed by the risk that comes with the weight gain.

"The patient has to decide what is more important--aesthetic looks or their health," he continued, adding that most patients who successfully stop smoking will then ultimately be able to lose the weight by changing their dietary and exercise habits.

Clair had no conflicts of interest. Disclosures for the coauthors are listed in the paper. Fiore reported institutional support from Pfizer for a phase 4 study of varenicline; Baker reported no disclosures.