Time to peak glucose predicts prediabetes risk in healthy adults

ORLANDO, Fla. — In healthy adults, the time to peak glucose level during an oral glucose tolerance test is an indicator of beta-cell function independent of overall glycemic status, according to study data presented here.

“The time to reach peak blood glucose during an [OGTT] may be a simple, valuable tool for identifying people who are at high risk for prediabetes and may benefit from early treatment,” Stephanie T. Chung, MBBS, FAAP, an assistant clinical investigator with the National Institute of Diabetes and Digestive and Kidney Diseases with the NIH, told Endocrine Today. “This measure was a better predictor of pancreatic function and indicator of prediabetes than assessing glucose curve shape.”

Chung and colleagues analyzed data from 128 healthy adults who underwent a standard, 75-g OGTT (mean age, 43 years; 79% women; 47 black; mean BMI, 29.2 kg/m²). Researchers measured levels of glucose, insulin and C-peptide at baseline and at 30, 60, 90 and 120 minutes; researchers stratified the group according to a blood glucose “peak” before and after 30 minutes. Glucose area under the curve (AUC) was calculated; all participants also underwent an insulin-modified frequently sampled IV glucose test (IM-FSIGT) 1 to 2 weeks after the OGTT. Prediabetes was defined using 2016 American Diabetes Association criteria.

Within the cohort, glucose peak occurred at 30 minutes or later for 60% of participants (n = 76); prediabetes was identified in 34% (n = 43).

Among those with a glucose peak of 30 minutes or greater, researchers found that the odds of having prediabetes was five times greater (OR = 5.26; 95% CI, 2.1-13.1). A later glucose peak was also associated with older age, higher BMI, higher AUC and lower insulin sensitivity, according to researchers, as well as lower beta-cell function and a lower disposition index.

In multiple regression analysis, time to glucose peak and AUC were both independent predictors of disposition index (P < .01), and the relationship persisted when the cohort was stratified by prediabetes status (P = .03 for prediabetes and normal glucose tolerance).

“The time to peak glucose could enhance prediabetes risk stratification, as it indicates pancreatic function independent of insulin levels during a single oral glucose tolerance test,” Chung said. – by Regina Schaffer

Reference:

Chung ST, et al. OR14-1. Presented at: The Endocrine Society Annual Meeting; April 1-4, 2017; Orlando, Fla.

Disclosure: Chung reports no relevant financial disclosures.