Diabetes increases late-life risk of thyroid cancer

While previous studies have suggested that diabetes increases a person's lifetime risk of developing thyroid cancer, a new report has announced that this association appears to hold true for retirement-age Americans.

Published in the journal Thyroid, the investigation was conducted by epidemiologists associated with the National Cancer Institute (NCI) and the National Institutes of Health (NIH). In brief, researchers found that the presence of diabetes increased the 10-year risk of thyroid cancer by one-quarter among adults 50 to 71 years old.

The team based its conclusions on data collected from the nearly 500,000 men and women who participated in the NIH-American Association of Retired Persons (AARP) Diet and Health Study, which was conducted in 1995 and 1996.



During the initial survey, statisticians collected health information through the use of questionnaires. Volunteers were asked about their pancreatic health, body mass index, diabetic status and other physical wellness factors.



A decade later, researchers performed follow-up diagnostic tests on many participants. The new study used figures collected during these visits.

The team found that on the initial questionnaire, almost one in 10 volunteers reported having diabetes. Years later, these individuals developed thyroid cancer with greater average frequency than those without the metabolic disorder.

In all, diabetic participants were 25 percent more likely than their peers to be diagnosed with thyroid cancer. Women were at a particularly high risk.

While diabetic men experienced a 4 percent increase in the likelihood of developing thyroid tumors, diabetic women saw their risk jump by 46 percent, the team said.

These results fall more or less in line with figures published 10 years prior in the journal Clinical Diabetes. In an issue appearing in 2000, Patricia Wu, an endocrinologist from the University of California, San Diego estimated that 6.6 percent of the U.S. populace has some type of thyroid disease. By contrast, 10.8 percent of diabetics suffer from thyroid conditions, she wrote.

Why should diabetes be associated with greater chances of developing thyroid cancer?

No one is quite sure, though scientists believe that the connection may lie in the conditions' similarities as endocrine disorders. Thyroid Today notes that both diseases are linked to autoimmune problems, body mass and age-related risk.