Breast cancer risk increases with weight gain after age 35, finds study

In In The News by Barbara Jacoby

By: Elana Gotkine

From: medicalxpress.com

The risk for breast cancer is increased with weight gain after age 35 years, according to a research letter recently published in Cancer Biology & Medicine.

Katherine De la Torre, from the Seoul National University College of Medicine in South Korea, and colleagues conducted a prospective study to examine the association between weight change throughout distinct lifetime periods and stratified by menopausal status. A total of 73,192 Korean women (aged 40 to 69 years) were prospectively followed during a median follow-up of 9.2 years.

The researchers found 790 new breast cancer cases among 66,870 women with information on weight at 35 years of age. Of these women, 10.72, 32.68, and 35.92 percent had , maintained stable weight, and gained >5.0 kg, respectively. Compared with women with stable weight, those who gained >10 kg after 35 years of age had an increased risk for breast cancer (hazard ratio, 1.41).

Among premenopausal women, gaining 5 to 9.9 kg and ≥10 kg after 35 years of age increased the risk for breast cancer (hazard ratios, 1.89 and 2.23, respectively), with a dose-response effect. Women who gained >0.75 kg per year after age 35 years had an increased risk for breast cancer when a linear weight increment was assumed (hazard ratio, 1.35), but there were no associations based on menopausal status.

“Our research points to the critical period after age 35 as a potential window for weight management interventions aimed at prevention,” lead author Daehee Kang, M.D., Ph.D., also from Seoul National University Hospital, said in a statement.