NIH Study: Benefits of Quitting Smoking Outpace Risk of Modest Weight Gain
Post-cessation weight gain does not increase cardiovascular risks for former smokers (Mar. 13)
The improvement in cardiovascular health that results from quitting smoking far outweighs the limited risks to cardiovascular health from the modest amount of weight gained after quitting, according to a community study funded by the National Institutes of Health (NIH). The study found that former smokers without diabetes had about half as much risk of developing cardiovascular disease as current smokers, and this risk level did not change when the analysis accounted for post-cessation weight gain.
The new research was published in the March 13 issue of JAMA.
“Our findings suggest that a modest weight gain, around 5 to 10 pounds, has a negligible effect on the net benefit of quitting smoking,” said study co-author Caroline Fox, MD, MPH. “Being able to quantify to some degree the relationship between the benefits and side effects of smoking cessation can help in counseling those who have quit or are thinking about quitting.”
Fox added that the analysis could not definitively determine the effect of modest weight gain in former smokers with diabetes, although the numbers suggested a similar trend. She noted that follow-up studies to confirm the effect of weight gain in people with diabetes would be important, as weight control is a key factor in managing diabetes and in preventing diabetes-related heart problems.
The researchers analyzed data collected between 1984 and 2011 from 3,251 participants enrolled in the Framingham Heart Study. During this period, participants received periodic medical examinations so that researchers could calculate changes in weight and smoking status. The participants were divided according to whether they had diabetes or not, and then were further divided into four smoking categories: smokers, nonsmokers, recent quitters (quit for 4 years or less), and long-term quitters (quit for more than 4 years). The researchers then examined the occurrence of cardiovascular problems — such as coronary heart disease, stroke, or heart failure — in each group.
The initial analysis, which did not account for changes in weight, found that former smokers without diabetes had about half as much risk of cardiovascular problems as smokers (0.47 and 0.46 times the risk for recent and long-term quitters, respectively). In comparison, nonsmokers had about one-third as much risk (0.32).
The researchers then made statistical adjustments to account for the fact that recent quitters gained more weight on average than other groups (about 6.5 pounds). The researchers found that even accounting for weight, the reduced risk remained nearly the same for recent quitters (increasing slightly from 0.47 to 0.49 times the risk). The reduced risk for long-term quitters and nonsmokers remained constant when the data were adjusted for weight gain.
Source: NIH; March 13, 2013.