A Safer Heart After Kicking the Habit

Quitting smoking reduced coronary heart disease risk even in women who gained weight after quitting

(RxWiki News) Breaking the tobacco habit is a sensible goal of many smokers. Meeting that target has clear payoffs. For some, including older women, it also may raise concerns about weight gain.

A new study linked quitting smoking with lower risks of coronary heart disease in post-menopausal women.

This study also showed that some women in this age group who gained weight after kicking the habit didn't always achieve the same level of heart protection as those who did not gain weight.

Still, these findings suggest that quitting smoking may reduce the risk of coronary heart disease in some women even when they gain weight after quitting.

"Quit smoking to protect your heart."

Juhua Luo, PhD, an epidemiologist and biostatistician at Indiana University's School of Public Health, was lead author of this study.

Dr. Luo and his fellow researchers investigated the medical records of 104,391 women, aged 61 through 63, for about three years. These women had been enrolled in the Women's Health Initiative, which tracked, among others, post-menopausal women beginning in 1993.

At the start of this study, none of the women had coronary heart disease. At the end of the study period, 3,381 women had developed coronary heart disease.

Out of the entire group, 98,053 told the researchers they did not have diabetes at the start of the study. The remainder did have diabetes.

Of those without diabetes, 3.3 per 1,000 women who had never smoked were found to have developed coronary heart disease after three years. Among former smokers without diabetes, 3.7 per 1,000 developed coronary heart disease.

Of the women without diabetes who had recently quit smoking, 3.7 per 1,000 developed coronary heart disease. Of the current smokers without diabetes, 7.6 per 1,000 developed coronary heart disease. 

These findings meant that, compared to current smokers, women without diabetes who had quit smoking at some point during the three study years were about 75 percent less likely to develop heart disease than current smokers. Former smokers without diabetes were about 40 percent less likely than current smokers to have developed coronary heart disease.

Among the remaining 6,338 women who had diabetes at the start of the study, those who had never smoked were 36 percent less likely than current smokers to develop coronary heart disease. Those who had recently quit smoking were 37 percent less likely than current smokers to develop coronary heart disease. Former smokers with diabetes were about 43 percent less likely than current smokers to develop coronary heart disease.

For women with and without diabetes, gaining less than about 10 pounds did not affect their heart disease outcomes, the researchers concluded.

These researchers also concluded that women without diabetes who used to smoke or who never smoked and gained between about 10 and 22 pounds all had lower heart disease risks than current smokers who also gained weight.

There were not enough women with diabetes who gained at least 22 pounds to determine any potential heart health effects for that group, researchers found.

"Smoking cessation was associated with a lower risk of [coronary heart disease] among post-menopausal women with and without diabetes," the researchers wrote. 

"Weight gain following smoking cessation weakened this association, especially for women with diabetes who gained [about 10 pounds] or more, although [findings] power was limited in this sub-group due to the small number of cases," they wrote.

"Other limitations of the study are that it included only post-menopausal women and did not account for further changes in smoking, weight or diabetes status after year 3," they wrote.

This study was published July 2 in the Journal of the American Medical Association.

The researchers did not report any investments or other activities that would affect study design or outcomes.

Review Date: 
June 27, 2013