One-hour glucose to predict prediabetes (PreDM=155mg/dL) and type 2 diabetes (T2D= 209 mg/dl) could improve detection with a shorter 1-hour OGTT, but thresholds need validation in longitudinal cohorts. We determined the risk of incident diabetes using the proposed thresholds with a 16-year longitudinal Korean data set (N=6381, BMI=24±4.0 kg/m2; Age 51.2±8.6 y). OGTT was conducted every 2 y, and 3 groups were assigned at baseline: low one-hour plasma glucose (1h-PG) with normal glucose tolerance (NGT) (low 1h-PG: FPG<100, 2h-PG<140, 1h-PG<155), high 1h-PG with NGT (high 1h-PG: FPG<100, 2h-PG<140, 1h-PG≥155), and PreDM (100≤FPG<126 or 140≤2h-PG<200). Time to T2D was compared by the group in a subset (N=230). T2D risk was higher in high 1h-PG and PreDM than low 1h-PG group (HR:4.9 [3.5, 6.8] and 8.8 [6.5, 11.8]). With the subset of progressors, a linear mixed effect model showed that times to T2D from low and high 1h-PG were 24.8±18.5 y and 19.5±12.4 y (P<0.05). The 1h-PG threshold for T2D, 209 mg/dl, was reached 7.5±14.5 y earlier than the 2h-PG threshold, 200 mg/dl. Conclusion: NGT with high 1h-PG is an intermediate state between low 1h-PG NGT and PreDM, and the 1h-PG threshold for T2D allows earlier diagnosis than the current 2h-PG threshold.


M.Im: None. I.Kim: None. S.T.Chung: None. A.Sherman: None. J.Ha: None. S.Kim: None. S.Ryang: None. D.Kim: None. W.Yi: None. J.Kim: None. H.Kang: None. Y.Kim: None. Y.Kim: None. M.Kim: None.


Busan Economic Promotion Agency; National Research Foundation of Korea (2022H1D3A2A01063552); Korea Health Industry Development Institute (HI18C2383); dkNET New Investigator Pilot Program in Bioinformatics; National Institute of Diabetes and Digestive and Kidney Diseases

Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered. More information is available at