Glycosylated hemoglobin (HbA1c) measurements in combination with fasting laboratory tests and clinic data provide useful prediction for type 2 diabetes risk, according to a prospective analysis published in Diabetes Care.
In this prospective study, investigators included white (n = 11,244) and black (n = 2294) patients without diabetes who were participants in the Framingham Heart Study and Atherosclerosis Risk in Communities study. The investigators sought to determine whether HbA1c was associated with a diabetes risk in the scenarios where HbA1c, clinic data, fasting laboratory tests, or clinic data and fasting laboratory test data were available.
A total of 3315 patients included in this cohort developed type 2 diabetes over the course of 20 years. For each percentage unit HbA1c increase, the odds of type 2 diabetes increased 2.7- to 4.5-fold (odds ratio [OR], 4.50; 95% CI, 3.35-6.03) in both white and black participants.
In white participants, the use of HbA1c only, as well as HbA1c in addition to clinic data, provided improved predictive value for type 2 diabetes (P <.05). Overall, the data demonstrated that HbA1c, in addition to other available clinical data, is a useful tool for identifying patients at risk for diabetes.
This study included a small sample size and a limited range of ethnicities. Therefore, the findings cannot be generalized across the entire population. In addition, this study did not determine whether HbA1c is useful for predicting diabetes risk in older individuals.
According to the findings, HbA1c is a useful prognostic indicator for type 2 diabetes risk and “has a central place in [type 2 diabetes] prevention efforts” and in “identifying high-risk individuals so that preventive measures can be targeted at those who may need them the most.”
Leong A, Daya N, Porneala B, et al. Prediction of type 2 diabetes by hemoglobin A1c in two community-based cohorts [published online October 26, 2017]. Diabetes Care. doi: 10.2337/dc17-0607