Endocrine Abstracts

Background: In subjects with long duration of type 2 diabetes (T2DM), strict glycaemic control fails to decrease the incidence of cardiovascular disease (CVD). Impaired vascular indices have been associated with adverse cardiovascular prognosis in T2DM. We examined whether intensive glycaemic control in T2DM patients improves vascular indices.

Methods: We studied 68 T2DM patients (64±9 years, 52% males, and T2DM duration 14±10 years) with poor glycaemic control (HbA1c ≥7.5%), at baseline and 6–12 months after intensive treatment to achieve optimal glycaemic control. Brachial artery flow-mediated dilation (FMD), carotid–femoral pulse wave velocity (PWV), central augmentation index (AIx), large and small artery elasticity indices, common carotid intima–media thickness (cIMT), and ankle–brachial index were measured.

Results: Improvement of HbA1c >0.5% was achieved in 55 (81%) patients (HbA1c decrease from 9.6±1.8 to 7.3±1.0%, P<0.001). In this group of patients, triglycerides decreased (177±140–137±73 mg/dl, P=0.008), cIMT increased (0.70±0.20–0.74±0.22 mm, P=0.038), and large artery distensibility decreased (14.2±5.2–12.4±4.1 AU, P=0.045) at follow-up, while no other changes in vascular indices, blood pressure, lipids, or other laboratory values were found. No difference in vascular indices’ changes at follow-up was observed between patients with or without improved glycaemic control (repeated measures (RM)-ANOVA, P=NS for all). When patients with improved glycaemic control were compared based on T2DM duration, AIx was decreased in those with short disease duration (<5 years), while it remained unchanged in those with >5 years duration (RM-ANOVA, P=0.013).

Conclusions: In T2DM patients, agressive glycaemic control without concomitant improvement in other cardiovascular risk factors was not associated with an improvement in vascular function indices at 6–12 months. However, in patients of <5 years duration, intensive glycaemic control improved only augmentation index, a combined index of aortic stiffness and peripheral vascular function. Multifactorial interventions of longer duration are needed to improve cardiovascular risk in T2DM.