Glycaemic status influences the nature and severity of coronary artery disease

We sought to understand the relationships between glycaemic status and both severity and progression of coronary artery disease (CAD), the leading cause of death in diabetes.

Baseline fasting blood glucose (FBG) and HbA_1c (%) were measured in 426 patients with known or suspected stable CAD, who underwent coronary artery intravascular ultrasound (IVUS) at baseline and after a mean follow-up period of 664 days (range 257 to 961). The patients were categorised as normoglycaemic (n = 226, 53%), or as having impaired fasting glucose (n = 118, 28%) or diabetes (n = 82, 19%).

The maximum percentage coronary atheroma area at baseline was greater in diabetic patients (73.33 ± 8.86%) than in those with normoglycaemia (69.08 ± 10.43%; p = 0.001) and impaired fasting glucose (69.32 ± 9.59%; p = 0.0031). In averaged IVUS measurements of the 30-mm target segment (n = 332 participants), change in percentage atheroma area during follow-up was also greater in the diabetes (1.86 ± 3.90%) than in other groups (0.28 ± 3.32% and 0.56 ± 2.96%, p = 0.0047 global). FBG correlated with maximum percentage atheroma area at baseline (r = 0.17; p = 0.0003). HbA_1c also correlated with maximum percentage atheroma area at baseline (r = 0.26; p = 0.0001) and with change in maximum plaque area (r = 0.16; p = 0.016). A similar pattern of results occurred with plaque volume. The relationships between diabetes or HbA_1c and both IVUS measurements of plaque burden and remodelling persisted after adjustment.

Fasting blood glucose, HbA_1c and the presence of diabetes are associated with the severity and progression of coronary atherosclerosis. These observations support the hypothesis that better glycaemic control may favourably influence CAD in patients with abnormal glucose tolerance or diabetes.