Aims: The incidence of cardiac events is increased in diabetic patients even after lipid-lowering therapy. This study aimed to compare the statin-induced changes in the characteristics of vulnerable plaques in patients without diabetes mellitus (DM) and in those with better- or poorly controlled DM, measured by optical coherence tomography (OCT).
Methods: This was a retrospective study of 99 non-culprit lipid-rich plaques from 75 patients who underwent intensive OCT imaging examination. Thirty-four non-diabetic patients were assigned to Group A. According to the average HbA1c level, 22 diabetic patients were assigned to Group B, and 19, to Group C (average HbA1c < 8 and ≥8 %, respectively).
Results: Following 12 months of statin therapy, similar improvements in serum lipid levels were observed in the three groups. However, the increase in fibrous-cap thickness of plaques was the highest in Group A (Group A, 183 %; Group B, 104 %; and Group C, 53 %). Significant reductions in lipid volume index were observed in Groups A and B (Group A: -12 %, P < 0.001; Group B: -13 %, P = 0.038; Group C: 7 %, P = 0.948). Percent changes in OCT measurements were significantly correlated with average HbA1c in patients.
Conclusions: Improved glucose control may enhance the statin-induced reduction in characteristics of vulnerable plaque in diabetic patients.
Keywords: Atherosclerosis; Coronary artery disease; HbA1c; Optical coherence tomography; Statin.