Efficacy of 1-hour postload plasma glucose as a suitable measurement in predicting type 2 diabetes and diabetes-related complications: A post hoc analysis of the 30-year follow-up of the Da Qing IGT and Diabetes Study.

ABSTRACT

AIM: To evaluate whether 1-hour plasma glucose (1hPG) can be a comparable measurement to 2-hour plasma glucose (2hPG) in identifying individuals at high risk of developing diabetes. METHODS: A total of 1026 non-diabetic subjects in the Da Qing IGT and Diabetes Study were included and classified according to baseline postload 1hPG. The participants were followed up and assessed at 6-, 20- and 30year follow-up for outcomes including diabetes, all-cause and cardiovascular mortality, cardiovascular disease (CVD) events, and microvascular disease. We then conducted a proportional hazards analysis in this post hoc study to determine the risks of developing type 2 diabetes and its complications in a '1hPG-normal' group (1hPG <8.6 mmol/L) and a '1hPG-high' group (≥8.6 mmol/L). The predictive values of 1hPG and 2hPG were evaluated using a time-dependent receiver-operating characteristic (ROC) curve. RESULTS: Compared with the 1hPG-normal group, the 1hPG-high group had increased risk of diabetes (hazard ratio [HR] 4.45, 95% CI 3.43-5.79), all-cause mortality (HR 1.46, 95% CI 1.07-2.01), CVD mortality (HR 1.84, 95% CI 1.16-2.95), CVD events (HR 1.39, 95% CI 1.03-1.86) and microvascular disease (HR 1.70, 95% CI 1.03-2.79) after adjusting for confounders. 1hPG exhibited a higher area under the ROC curve (AUC) for predicting diabetes than 2hPG during the long-term follow-up (AUC [1hPG vs. 2hPG] 10 years 0.86 vs. 0.84, p = 0.08; 20 years 0.88 vs. 0.87, p = 0.04; 30 years 0.85 vs. 0.82, p = 0.009). CONCLUSIONS: Elevated 1hPG level (≥8.6 mmol/L) was associated with increased risk of developing type 2 diabetes and its long-term complications, and could be considered as a suitable measurement for identifying individuals at high risk of type 2 diabetes.