People with a family history of Type 2 diabetes have an increased risk of developing prediabetes, according to a new analysis from the German Center for Diabetes Research. Approximately 79 million people in the United States currently have prediabetes.
Prediabetes is a condition in which blood glucose levels are elevated, but are not high enough to be classified as Type 2 diabetes. An A1C level from 5.7–6.4% indicates prediabetes, as does a blood glucose level from 100–125 mg/dl on a fasting plasma glucose test or a blood glucose level of 140–199 mg/dl on an oral glucose tolerance test. (A diagnosis must be confirmed by another test on a subsequent day.) People with prediabetes are at high risk for developing Type 2.
A family history of Type 2 diabetes is known to increase a person’s risk for developing diabetes. To determine whether a family history of Type 2 is also associated with an increased risk for prediabetes, researchers looked at data from 8,106 people without diabetes collected in four study centers around Germany. Among the participants, 5,482 had normal blood glucose levels while 2,624 had prediabetes.
Analyzing whether having at least one first-degree relative with Type 2 was associated with prediabetes, the researchers found that a family history of diabetes increased the risk of having prediabetes by 40%. When they adjusted for age, sex, and body-mass index (a measure of weight relative to height), the risk fell to 26%.
Further analysis revealed that the association between a family history of diabetes and prediabetes was seen only in people who were not obese. According to the study authors, “This might indicate [that] the effect of family history on prediabetes becomes readily measurable only when not overshadowed by strong risk factors such as obesity.”
For more information, read the article “Family History of Diabetes Increases the Risk of Prediabetes by 26 Percent, With Effect Most Evident in Non-Obese” or review the study’s abstract in the journal Diabetologia. And to learn more about prediabetes, see this page from Joslin Diabetes Center.