Background and Purpose--Type 2 diabetes is associated with a high cardiovascular morbidity and mortality. Recent advances of intervention studies in type 2 diabetes with use of carotid intima-media thickness (CIMT) measurement as a surrogate end point may allow for better understanding of the undetermined process of atherosclerosis, the effect of interventions, and the usefulness of CIMT to inhibit events of cardiovascular disease.

Summary of Review--Data were available from 11 studies (n=1578) in subjects with type 2 diabetes (including impaired glucose tolerance, n=132) that evaluated the effect of interventions on change in CIMT. The overall weighed rate of change in mean CIMT based on data among control groups (ie, type 2 diabetes without interventions) was 0.034 mm/y (95% CI, 0.029 to 0.039; median SD, 0.054), in which mean HbA_1c was 7.86% (95% CI, 7.72 to 8.00; median SD, 1.5). A significant close correlation of HbA_1c with rate of CIMT change was found (R²=0.35, P=0.01). Agents for lowering of blood glucose, platelet activation, or blood pressure significantly reduced the CIMT increase, independent of blood glucose control. This implies that other mechanisms of such agents to diminish CIMT increase should be explored.

Conclusions--CIMT measurement may contribute to elucidating the short- and/or long-term effect of interventions on the rate of change in CIMT in relation to the levels of various risk factors. Although the method needs further standardization, pharmacological interventions are likely to inhibit progression of CIMT, leading to a reduction of cardiovascular events.