Impact of blood glucose variability on carotid artery intima media thickness and distensibility in type 1 diabetes mellitus

Aims. Diabetes mellitus is characterized by structural and functional alterations of the large- and medium-size arteries. Whether blood glucose variability, i.e. the glycemic oscillations occurring during the 24-h period, represents a risk factor for vascular alterations additional to and independent on HbA1c in type 1 diabetes mellitus is still undefined. The present study was carried out with the aim at investigating the impact of different measures of blood glucose variability on arterial structure and function. We studied 17 non-complicated type 1 diabetic patients (11 males, six females) with an age of 40.8 ± 7.6 years (mean ± SD). In each patient, 24-h glucose profile was obtained by continuous glucose monitoring system and glucose variability was expressed as mean ± SD of 24-h blood glucose levels, mean amplitude of glycemic excursions and postprandial hyperglycemic spikes. Arterial structure and function was measured as carotid IMT and stiffness. Major findings. The different approaches to assessing blood glucose variability well correlated between and with HbA1c. Carotid IMT and stiffness showed significant correlations with age, blood pressure, heart rate and daily insulin intake but a non- significant correlation with blood glucose variability. Principal conclusion. Thus, in type 1 diabetes mellitus, measures of glycemic variability are useful in predicting both actual and long-lasting glycemic control. In absence of diabetes-related complications and of any intima-media thickness alterations, the major predictors of arterial distensibility are represented by traditional risk factors beside glycemic 24-h control.