Revised Standards of Care Call for Changing How Gestational Diabetes Should Be Diagnosed
December 29, 2010
The American Diabetes Association is recommending changes in the way pregnant women are tested for gestational diabetes, which will likely result in a doubling of the number of women diagnosed, but should also reduce the health risks to mother and baby.
The new testing guidelines will be published in a special supplement to the January issue of Diabetes Care as part of the Association’s revised Standards of Medical Care, which are updated annually to provide the best possible guidance to health care professionals for diagnosing and treating adults and children with all forms of diabetes. The Standards are based upon the most current scientific evidence, which is rigorously reviewed by the Association’s multi-disciplinary Professional Practice Committee.
Currently, there are inconsistent standards around the world for how women are tested for gestational diabetes – a type of diabetes that comes on during pregnancy and resolves after delivery – as well as inconsistent cutpoints for diagnosis. Recent evidence from the Hyperglycemia and Adverse Pregnancy Outcomes (HAPO) study, a multinational epidemiologic study, has shown that the risk of adverse maternal, fetal and neonatal outcomes rises in direct relation to the mother’s glucose levels. It also found that risks are present at glucose levels previously felt to be normal (below prior cutpoints for diagnosing gestational diabetes). Therefore, the International Association of Diabetes and Pregnancy Study Groups, a consensus group which includes the Association, developed new recommendations using the HAPO data for the testing and diagnosis of diabetes during pregnancy. The American Diabetes Association has officially adopted these recommendations.
The new recommendations call for testing all women not previously known to have diabetes using the 75-gram oral glucose tolerance test (OGTT) between 24 and 28 weeks of gestation and using diagnostic cutpoints of greater than 92 mg/dl for the fasting glucose test; greater than 180 mg/dl one hour after drinking the 75-gram glucose solution; and greater than 153 mg/dl two hours after drinking the glucose solution.
The new guidelines also call for testing all pregnant women with risk factors for type 2 diabetes at their first prenatal visit, due to the rising prevalence of undiagnosed type 2 diabetes in women of childbearing age. However, a diagnosis at this stage would be considered a diagnosis of type 2 diabetes and not gestational diabetes.
“We support a world-wide, uniform definition of gestational diabetes, and this is the best way to get there,” said Dr. Carol Wysham, Chair of the Professional Practice Committee. “However, we also recognize that health systems need time to convert to the new strategy and in the interim, they can continue to use prior methods for diagnosis until they can make the switch. It’s important that they do ultimately convert, though, as the new definition will enable us to ward off preventable complications in both mother and child.”
Under the current guidelines, roughly 135,000 women in the United States are diagnosed with gestational diabetes each year, or 4 percent of all pregnant women. This figure is expected to double under the new diagnostic criteria, though the additional diagnoses will be women with mild GDM that can generally be treated with lifestyle change (diet and exercise). More severe cases of GDM, which were generally picked up with the older criteria, may require the mother to take insulin. Left untreated, gestational diabetes can lead to overweight babies, complications during delivery and a higher risk for both mother and child to develop type 2 diabetes later in life.
Other changes in the 2011 Standards of Medical Care include:
• A new section on Transitions to Care for Youth with Diabetes that addresses the problem of older teens and young adults often disengaging from the health care system.
• A new section on Monogenic Forms of Diabetes, a rare situation in which only one gene is affected (type 1 and type 2 are polygenic, or impact multiple genes).
• Revisions to the section on blood pressure control to reflect new evidence reinforcing the importance of individualized blood pressure goals.
• The addition of a table of suggested monitoring for and management of complications of more advanced chronic kidney disease.
Diabetes Care, published by the American Diabetes Association, is the leading peer-reviewed journal of clinical research into one of the nation’s leading causes of death by disease. Diabetes also is a leading cause of heart disease and stroke, as well as the leading cause of adult blindness, kidney failure, and non-traumatic amputations.
The American Diabetes Association is leading the fight to Stop Diabetes and its deadly consequences and fighting for those affected by diabetes. The Association funds research to prevent, cure and manage diabetes; delivers services to hundreds of communities; provides objective and credible information; and gives voice to those denied their rights because of diabetes. For the past 75 years, our mission has been to prevent and cure diabetes and to improve the lives of all people affected by diabetes.