(HealthDay News) — For postmenopausal women, modest weight loss is associated with reduced breast cancer risk, according to a study presented at the annual San Antonio Breast Cancer Symposium, held from Dec. 5 to 9 in Texas.
Rowan Chlebowski, M.D., Ph.D., from City of Hope in Duarte, Calif., and colleagues examined the correlation between weight change and invasive breast cancer risk in 61,335 postmenopausal women in the Women’s Health Initiative Observational Study with no prior breast cancer and normal mammogram. Weight change was categorized over three years as stable, loss, or gain.
The researchers found that 3,061 women developed invasive breast cancer during a mean follow-up of 11.4 years. Women with weight loss (≥5 percent) had a significantly lower breast cancer risk than women with stable weight, in multivariable analysis (hazard ratio, 0.88). The findings were not altered by adjustment for mammography (hazard ratio, 0.88). Breast cancer risk was even lower for women with weight loss of ≥15 percent (hazard ratio, 0.63). Women with weight gain had significantly increased risk of triple-negative breast cancer (hazard ratio, 1.54), but there was no association for weight gain with overall breast cancer risk.
“In the three-year window of the study, relatively modest weight loss was associated with significant lowering of breast cancer incidence,” Chlebowski said in a statement. “From this study, we have evidence that a weight loss strategy can be effective in lowering breast cancer risk in postmenopausal women.”
One author disclosed financial ties to the pharmaceutical industry.