High blood sugar levels in older women linked to colorectal cancer

Elevated blood sugar levels are associated with an increased risk of colorectal cancer, according to a study led by researchers at Albert Einstein College of Medicine of Yeshiva University. The findings, observed in nearly 5,000 postmenopausal women, appear in the Nov. 29 online edition of the British Journal of Cancer.

According to the , colorectal cancer is the third most commonly diagnosed cancer and the third leading cause of cancer death in both men and women in the U.S.

Statistics compiled by the U.S. Centers for Disease Control and Prevention for 2007 (the most recent year for which figures are available) show that 142,672 Americans were diagnosed with colorectal cancer, including 69,917 women; the 53,219 deaths from colorectal cancer that year were divided almost equally between men and women.

The Einstein study involved women who were enrolled in the National Institutes of Health's landmark Women's Health Initiative study. For these women, fasting blood sugar and insulin levels had been measured at baseline (i.e., the start of the study) and then several more times over the next 12 years.

By the end of the 12-year period, 81 of the women had developed colorectal cancer. The researchers found that elevated baseline were associated with increased colorectal cancer risk—and that women in the highest third of baseline glucose levels were nearly twice as likely to have developed colorectal cancer as women in the lowest third of blood glucose levels. Results were similar when the scientists looked at repeated glucose measurements over time. No association was found between insulin levels and risk for colorectal cancer.

Obesity—usually accompanied by elevated blood levels of insulin and glucose—is a known risk factor for colorectal cancer. Researchers have long suspected that obesity's influence on colorectal cancer risk stems from the elevated it causes. But the Einstein study suggests that obesity's impact on this cancer may be due to elevated glucose levels, or to some factor correlated with elevated glucose levels.

"The next challenge is to find the mechanism by which chronically elevated blood glucose levels may lead to ," said Geoffrey Kabat, Ph.D., a senior epidemiologist at Einstein and lead author of the paper. "It's possible that elevated glucose levels are linked to increased blood levels of growth factors and inflammatory factors that spur the growth of intestinal polyps, some of which later develop into cancer."

More information: The paper is titled "A Longitudinal Study of Serum Insulin and Glucose Levels in Relation to Colorectal Cancer Risk among Postmenopausal Women."

Related Stories

Metabolic factors may play a role in risk for breast cancer

Jun 30, 2009

Physiological changes associated with the metabolic syndrome may play a role in the risk of postmenopausal breast cancer, according to study results published in Cancer Epidemiology, Biomarkers & Prevention, a journal of the ...

Recommended for you

Scientists zero in on how lung cancer spreads

Dec 24, 2014

Cancer Research UK scientists have taken microscopic images revealing that the protein ties tethering cells together are severed in lung cancer cells - meaning they can break loose and spread, according to ...

Scientists identify rare cancer's genetic pathways

Dec 24, 2014

An international research team, including four Simon Fraser University scientists, has identified the "mutational landscape" of intrahepatic cholangiocarcinoma (ICC), a rare, highly fatal form of liver cancer that disproportionately ...

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.