Although quitting cigarettes helps the heart and lungs, a new study suggests that postmenopausal women who quit smoking need to guard against weight gain that can lead to diabetes.
"Still, stopping smoking substantially decreases the risk of developing heart disease for postmenopausal women with and without diabetes," said lead investigator Juhua Luo, an assistant professor of epidemiology and biostatistics at the Indiana University School of Public Health in Bloomington.
"However, because gaining more than 4kg may lessen the benefit, women should try to avoid gaining more than this amount," she said. "Our study shows that it is never too late to benefit from quitting smoking."
The report was published in the July 3 issue of the Journal of the American Medical Association.
In evaluating the study, Dr Norman Edelman, chief medical officer for the American Lung Association, said it is important to look at the number of women who gained weight.
"Only very few women had weight gain over 4 kg, and in those few the weight gain counteracted some of the cardiovascular benefit of smoking cessation," he said.
"To me, the most important finding in these data is that the vast majority of women were able to limit their weight gain to modest levels after smoking cessation and therefore were able to realize the considerable cardio-protective effect of smoking cessation," Edelman stated.
Not discussed in the study, but also of importance, is the considerable benefits to lung health – the reduced chance of chronic obstructive pulmonary disease (COPD) and lung cancer, Edelman added.
Luo's team collected data on nearly 162 000 women aged 50 to 79 who took part in the Women's Health Initiative study. Among more than 104 000 women followed for almost nine years, nearly 3 400 developed heart disease.
As expected, women who quit smoking had a lower risk of heart disease, the researchers found.
Women who had quit smoking for more than three years had a 61% lower risk of developing heart disease compared with women who continued smoking, Luo said.
Among more than 6 000 postmenopausal women with diabetes, those who quit smoking had about a 60% lower risk for heart disease compared with those who continued smoking, she added.
"The majority of women gained less than 4kg after quitting smoking. For the smaller number of women who gained more than 4kg, there was less heart disease benefit from stopping smoking, especially for women with diabetes," Luo said.
For more information on smoking cessation, visit the U.S. Centers for Disease Control and Prevention.