Testing for type 2 diabetes or even prediabetes can be done in a variety of ways. While not the most convenient or simple, these methods can include testing fasting plasma glucose levels (FPG), and 2-hour post-load plasma glucose concentration (2hPG). Especially when used in children, these methods are not the most convenient or feasible. However, a new longitudinal study published recently in Diabetes Care has indicated that HbA1c levels, a common, more convenient test, can be just as efficient as other traditional tests when screening for prediabetes or predicting the risk of developing type 2 diabetes, especially in children.
The study followed an American Indian population, a group known for a high incidence of type 2 diabetes, for over 40 years, from 1965-2007. Led by Madhumita Sinha, MD, from the National Institute of Diabetes and Digestive and Kidney Diseases, at the National Institutes of Health in Phoenix, Arizona, the study enlisted 2095 children without diabetes who were 10-19 years old at the beginning of their participation, and tracked these individuals until they were 39. Additionally, the researchers analyzed 2005 adults between the ages of 20-39 and tracked this group until they were 59. Of the children, approximately 70% were overweight or obese, and a similar trend was seen in the adults, where over 90% were classified as overweight or obese.
Overall, it was found that throughout the study, there was no significant difference between utilizing HbA1c levels to indicate prediabetes and predict the potential for eventually developing type 2 diabetes and other traditional, more invasive methods. Additionally, it was found that HbA1c levels were the most reliable in children and adult males, with male children with a high HbA1c level being four times more likely to develop diabetes over the course of follow up, and female children with high HbA1c showing a seven times greater chance of developing diabetes than their lower HbA1c counterparts. Adult females showed a slight deviance from the predictability trend, and while there is no concrete reason for this difference, it could be due to a higher prevalence of anemia (low blood iron) in adult women, which can have a significant impact on HbA1c readings.
A benefit to the study is that it was conducted in one facility, with one group of people, over many years. Although it does focus on a small demographic subset, the researchers do not doubt it’s generalizability. If the results found hold up, it could lead to less invasive, and much more convenient testing measures for individuals at risk for developing, or currently developing type 2 diabetes. A large proportion of this population resides in children, who the American Diabetes Association suggests should be screened for T2D, even if they are asymptomatic, starting when they are 10 years-old if they have a BMI greater than the 85th percentile for their gender and age, as well as any additional risk factors, including familial history of tyoe 2 diabetes. More convenient screening methods could lead to a higher prevalence of early detection of prediabetes, and could lead to more effective interventions at an earlier age.
Davenport, Liam. “HbA1c Predicts Diabetes Risk in Children and Adolescents.” Medscape. 4 Jan 2017. Available from: http://www.medscape.com/viewarticle/873974?nlid=111760_2981&src=wnl_dne_170105_mscpedit&uac=259022DR&impID=1267236&faf=1
Vijayakumar P, et al. “HbA1c and the prediction of Type 2 Diabetes in children and adults.” Diabetes Care. Jan 2017; 40(1): 16-21. Available from: https://doi.org/10.2337/dc16-1358