Glucose variability, blood pressure and arterial stiffness in type 1 diabetes

Aims: Evidence suggests that chronic hyperglycaemia predicts not only microvascular disease but also macrovascular disease, however it is not known whether it is the glucose variability per se or the total glucose exposure that confers risk. The objective of this study was to investigate whether daily glucose variability influence blood pressure and arterial stiffness, an early sign of macrovascular disease, at baseline and during a hyperglycaemic clamp in patients with type 1 diabetes. Methods: Twenty-two non-smoking male patients with type 1 diabetes without any diabetic complications, participated in the study. The patients were monitored for 72-h using a continuous glucose monitoring system. Before and during a 2-h hyperglycaemic clamp, blood pressure as well as pulse wave analysis and pulse wave velocity (PWV) were performed to assess arterial stiffness. Results: No correlation was observed between mean amplitude of glycaemic excursions (MAGE) and arterial stiffness at baseline. There was a correlation between mean daily glucose and aortic PWV even after adjusting for BMI, HbA_1c, and duration of diabetes in a multiple regression analysis (r = 0.48; P < 0.01). MAGE (r = 0.52; P < 0.01) correlated independently with the change in aortic DBP during the clamp. Conclusions: This study suggests that high mean daily blood glucose but not glucose variability per se is associated with arterial stiffness in patients with T1D. Daily glucose variability is positively associated with the change in central blood pressure during a hyperglycaemic clamp.