London – Breast Cancer Risk Rises with 2nd Hand Smoke

London – Smokers and women who quit up to 20 years previously are more at risk of the disease compared to other postmenopausal women who have never smoked or have never been around second-hand smoke, researchers said in Wednesday’s issue of the British Medical Journal.

Prof. Juhua Luo of the department of community medicine at West Virginia University and her co-authors looked for confirmed cases of invasive breast cancer among nearly 80,000 American women 50 to 79 years old who entered the study between 1993 and 1998.

Over an average followup of 10 years, 3,520 cases of breast cancer were found in the Women’s Health Initiative study, which is funded by the U.S. National Heart, Lung and Blood Institute.

Current smokers had 1.16 times the breast cancer risk compared to women who never smoked, the team found. Breast cancer risk was raised by 1.09 times among former smokers after menopause. Twenty years after butting out, the risk appeared drop off.

Breast cancer risk in a new study in the British Medical Journal rose the more women smoked and the longer they did so, researchers found. (Francois Mori/Associated Press)

“We were able to see the risk elevated in women who smoked as few as five to 15 cigarettes per day; but the more women smoked and the longer women smoked, the higher the risks, and it’s really pretty consistent,” said study co-author Dr. Karen Margolis, senior clinical investigator with HealthPartners Research Foundation in Minneapolis.

The link between increased risk of breast cancer and second-hand smoke was only found for extensive exposure — more than 10 years recalled during childhood, more than 20 years at home as an adult and more than a decade at work.

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