June 30 (HealthDay News) -- Women with high blood pressure, elevated glucose and other components of metabolic syndrome might be at increased risk for postmenopausal breast cancer, a new study suggests.

Metabolic syndrome, also known as insulin resistance syndrome, consists of a cluster of such conditions as abdominal obesity, high blood glucose levels, impaired glucose tolerance, abnormal lipid levels and hypertension.

The study included 4,888 women, ages 50 to 79, who did not have diabetes at the start of the study and were periodically tested for components of metabolic syndrome over eight years as part of their participation in the Women's Health Initiative study. During that time, 165 of them received breast cancer diagnoses.

The presence of metabolic syndrome at the start of the study was not associated with breast cancer risk. However, "women who had the metabolic syndrome during the three to five years prior to breast cancer diagnosis had roughly a doubling of risk," researcher Geoffrey C. Kabat, senior epidemiologist at the Albert Einstein College of Medicine in New York City, said in a news release from the American Association for Cancer Research.

The study also found that high diastolic blood pressure (bottom number) alone was associated with more than a twofold increased risk, whereas elevated triglyceride and glucose levels were each associated with about 1.7 times increased risk.

The findings appear in the July issue of the journal Cancer Epidemiology, Biomarkers & Prevention.

It is already known that metabolic syndrome, which is associated with poor diet and lack of exercise, can increase the risk for diabetes and heart disease.

"This study suggests that having the metabolic syndrome itself or some of its components may increase a woman's risk of postmenopausal breast cancer," Kabat said. "However, much more work is needed to understand the role of these metabolic factors and their interplay with better established breast cancer risk factors, such as reproductive and hormonal factors."

SOURCE: American Association for Cancer Research, news release, June 30, 2009