Clinical utility of 1-h post-load glucose in accelerating diagnosis of type 2 diabetes: a prospective cohort study

AIMS: To quantify the absolute time in months by which the 1-h post-load glucose (1-hPG) criterion advances the diagnosis of type 2 diabetes (T2D). METHODS: We analyzed data from 7,165 adults (≥ 40 years) without T2D at baseline in the Korean Genome and Epidemiology Study (KoGES). Participants were categorized into high (≥ 155 mg/dL) and low (< 155 mg/dL) 1-hPG groups and followed for a median of 11.5 years. The primary outcome, incident T2D, was analyzed using Cox proportional hazards models, while differences in time-to-diagnosis were determined through restricted mean survival time (RMST) analysis. RESULTS: High 1hPG was a strong independent predictor for incident T2D (adjusted Hazard Ratio: 2.88; 95% CIs: 2.55 − 3.26). After full adjustment, the high 1-hPG group had a diagnostic lead time of 11.1 months (95% CIs, 9.6 − 12.5) for T2D over a decade compared to the low 1-hPG group. This diagnostic advancement was more notable among individuals with prediabetes, expediting diagnosis by up to 15.9 months, and was consistent across sociodemographic factors and comorbidity subgroups. CONCLUSION: High 1-hPG advances the diagnosis of T2D by approximately 11 months over a decade, providing quantifiable diagnostic lead time in detecting high-risk individuals. These findings highlight the potential of 1-hPG as a supplementary tool to address the limited sensitivity of conventional screening tests. 1-hPG can aid in identifying high-risk individuals, particularly those with prediabetes, for early preventive interventions.