How to Test for Gestational Diabetes the Easy Way

A simple new blood test can accurately predict Type 2 diabetes risk better than traditional glucose measures among women with gestational diabetes.

An estimated 3 to 14 percent of women develop gestational diabetes, a condition that can raise risk of developing type 2 diabetes within 5 years by 20 to 50 percent. A better predictive test can help health care providers identify those who have the highest risk and perhaps motivate them to make necessary lifestyle changes to stave off the disease.

Although diabetes is typically diagnosed by observing increases in blood glucose levels, other metabolites may also signify a higher risk of type 2 diabetes in the future. These changes appear before the rise in blood glucose levels occurs. The team identified 21 metabolites that were significantly different in people with type 2 diabetes.

To develop the new test, a team of researchers tested fasting blood samples for from 1,035 women who had experienced gestational diabetes 6 to 9 weeks after giving birth. They screened for diabetes with a fasting blood test followed by a 2-hour oral glucose test and also screened for other metabolites using a technique called targeted metabolomics. Of the 1,010 women who did not already have type 2 diabetes at the start, 113 developed it within 2 years and another 17 developed it between 2 and 4 years later.

The targeted metabolomics predicted diabetes risk with 83 percent accuracy, which was significantly better than the conventional test. It was also much more convenient.

"After delivering a baby, many women may find it very difficult to schedule two hours for another glucose test," said co-lead author Michael Wheeler, PhD, professor in the Department of Physiology at the University of Toronto and senior scientist at the Toronto General Research Institute. "What if we could create a much more effective test that could be given to women while they're still in the hospital? Once diabetes has developed, it's very difficult to reverse."

The new method may also be useful for predicting risk among people in the general population. The team plans to continue testing the technique to evaluate differences among people of different ethnicities and those who are already at high risk.

"Early prevention is the key to minimizing the devastating effects of diabetes on health outcomes," said co-lead author Erica Gunderson, PhD, senior research scientist with Kaiser Permanente Northern California Division of Research in Oakland, Calif. "By identifying women soon after delivery, we can focus our resources on those at greatest risk who may benefit most from concerted early prevention efforts." The study appeared online ahead of print on June 23 in the journal Diabetes.