Association of postprandial and fasting plasma glucose with HbA1c across the spectrum of glycaemic impairment in type 2 diabetes

Dear Editor, Management of diabetes requires an understanding of the association between fasting plasma glucose (FPG), postprandial plasma glucose (PPG) and HbA1c—a tripartite model known as the glucose triad.1 A higher contribution of PPG relative to FPG in patients with HbA1c levels of ≤7% (53 mmol/mol) has been observed in a seminal article published in 20032 and further observed in several studies.3 Collectively, such data seem to make a convincing case for targeting postprandial glucose excursions in patients with mild hyperglycaemia. However, it has been questioned whether there is yet adequate evidence from clinical trials to support the safety and effectiveness of such a strategy. Therefore, the aim of the current post hoc analysis of the IMPROVE study4 was to utilise the large sample of patients with type 2 diabetes (N = 22,082) to assess the contribution of PPG and FPG to overall glycaemia and optimal glucose control. Crosssectional associations between PPG or FPG and HbA1c were examined by crude and multiple linear regression analyses at baseline and final study visits. Associations between absolute and relative change in PPG/FPG with change in HbA1c were also analysed.