One-hour postload glucose compared to prediabetes criteria as predictive markers of type 2 diabetes in Latin America

Background One-hour postload glucose (1h-PG) ≥ 155 mg/dL has been proposed as a marker of prediabetes and risk for type 2 diabetes (T2DM). However, direct comparison with other prediabetic criteria, also in different populations, could improve the prognostic approach for T2DM. Objective This study compared the prognostic value 1h-PG to traditional prediabetes criteria. Methods A cohort of 321 Peruvian patients with histories of impaired fasting glucose (IFG) underwent OGTTs and were followed for 7 years for T2DM development. Results Based on the OGTT, 56.6% of patients had confirmed IFG, 75.4% had normal glucose tolerance (NGT), and 24.6% exhibited IGT. Among NGT individuals, 58.7% had 1h-PG < 155 mg/dL and 41.3% presented 1h-PG ≥ 155 mg/dL. Elevated 1h-PG was associated with IFG, higher body mass index, glycated hemoglobin A1c, and plasma uric acid. Among those tested, 56% had glycated hemoglobin A1c ≥ 5.7%. Concordance between 1h-PG and prediabetes markers was weak. After 4.6 years, 24.3% of patients developed T2DM. Incidence was higher in those with 1h-PG ≥ 155 mg/dL (36.1%) and IGT (32.9%). Only IFG and 1h-PG ≥ 155 mg/dL were significantly associated with T2DM risk, with the latter showing the highest risk (risk ratio = 2.91; 95% CI [1.71-5.19]; P <.001). Patients with 1h-PG ≥ 155 mg/dL who progressed to T2DM had higher baseline uric acid levels than those with IGT. Conclusion 1h-PG ≥ 155 mg/dL is a solid predictor of T2DM, even among individuals with NGT, and may serve as a useful diagnostic criterion for prediabetes in Latin American populations and may be helpful to define a prediabetic phenotype.