Factors associated with carotid intima-media thickness and carotid plaques in type 2 diabetic patients

Abstract

Objective: Factors associated with carotid atherosclerosis are unclear in type 2 diabetic patients. The aim was to investigate the independent correlates of carotid intima-media thickness (IMT) and plaques in these individuals.

Methods: In a cross-sectional study, we measured carotid IMT at three sites (common carotid, bifurcation and internal carotid artery) and the severity of extracranial carotid artery (ECCA) atherosclerosis by plaque score in 441 type 2 diabetic patients. Nontraditional cardiovascular risk factors [ambulatory blood pressures (BPs), aortic stiffness, C-reactive protein and ankle-brachial index) were obtained. Multivariate linear and logistic regressions assessed the independent correlates of carotid IMT and ECCA plaque score.

Results: Patients with greater carotid IMT or plaque scores had worse clinical and laboratory profile than those with lower IMT and plaque scores, including higher BPs, aortic stiffness and prevalences of diabetic complications. On multivariate analysis, carotid IMT and plaques were mainly associated with older age, male sex, current-past smoking and ambulatory BPs, but not with clinic BPs. Night-time pulse pressure was the most important modifiable determinant of increased carotid IMT. No microvascular complication was independently associated with carotid atherosclerosis, except retinopathy for plaque score. Additionally, internal carotid IMT and plaque score were associated with ankle-brachial index in the subgroup of patients without macrovascular diseases.

Conclusion: In type 2 diabetic patients, older age, male sex, smoking status and ambulatory BPs, particularly night-time pulse pressure, were the main independent correlates of ultrasonographic carotid atherosclerosis. This finding reinforces the importance of ambulatory BP monitoring in type 2 diabetes management.