Postprandial 2-h glucose tolerance is associated with diabetes diagnosis, diabetes mortality, and cardiovascular mortality

Abstract

Abstract Postprandial plasma glucose between 4 and 7.9 h is associated with the diagnosis of diabetes, diabetes mortality, and cardiovascular mortality. However, it is unknown whether 2-hour plasma glucose during the oral glucose tolerance test conducted in this postprandial period (4–7.9 h), termed as 2-h PG OGTT@4–7.9 h , can accurately classify diabetes diagnosis and predict mortality risks. This study aimed to address these questions using 2,347 adult participants. Diabetes was defined as HbA 1c  ≥ 6.5%, and the ability of 2-h PG OGTT@4–7.9 h to classify diabetes was analyzed using receiver operating characteristic curves. Cox proportional hazards models were employed to estimate mortality hazard ratios (HRs) and 95% confidence intervals (CIs). The results showed that 2-h PG OGTT@4–7.9 h could classify diabetes with 92% accuracy. Participants were followed up for a mean of 21.4 years. A 1-square-root higher 2-h PG OGTT@4–7.9 h was associated with an increased risk of mortality from all causes (adjusted HR, 1.06; 95% CI, 1.04–1.08), diabetes (adjusted HR, 1.46; 95% CI, 1.33–1.61), and cardiovascular disease (adjusted HR, 1.07; 95% CI, 1.03–1.11). In conclusion, 2-h PG OGTT@4–7.9 h , a non-fasting test, may be useful for diabetes classification and prediction of mortality risk from diabetes and cardiovascular disease.