Effects of improved metabolic control on platelet reactivity in patients with type 2 diabetes mellitus following coronary angioplasty.

The aim of this study was to investigate the impact of improved metabolic control on platelet reactivity in patients with type 2 diabetes undergoing percutaneous coronary intervention (PCI). Twenty-two patients were randomised to intensive insulin or conventional treatment for diabetes. Platelet P-selectin expression was analysed before and three months after PCI. Metabolic control, as measured by level of glycosylated haemoglobin (HbA1c) and platelet P-selectin expression, was similar in the two treatment groups after three months. However, six of the 12 patients in the intensive group had increased levels of HbA1c after three months and three patients of the 10 in the conventionally treated group showed improved metabolic control. A re-analysis was performed, based on metabolic control. It showed that patients with improved control at three months (HbA1c 6.1% +/- 0.7 at baseline; 5.7% +/- 0.5 at three months; p<0.01; n=9) had lower ADP-induced P-selectin expression (p<0.05) than patients with worsened glycaemic control (HbA1c 5.9% +/- 1.0 at baseline; 6.5% +/- 1.4 at three months; p<0.01; n=13). Levels of HbA1c and fasting glucose were correlated to P-selectin expression (R=0.34 and R=0.31; p<0.05). We conclude from this study that improved glycaemic control reduces platelet reactivity in type 2 diabetes patients following PCI.

Thrombin activatable fibrinolysis inhibitor and hemostatic changes in patients with type I diabetes mellitus with and without microvascular complications.

We investigated thrombin activatable fibrinolysis inhibitor (TAFI) and its influence on fibrinolysis by measuring pro-TAFI activity and total TAFI antigen in 38 patients with type I diabetes mellitus (18 with and 20 without microvascular complications), as well as in 20 healthy controls. The pro-TAFI levels in the two groups of patients did not differ from those in the control group. Total TAFI antigen [i.e. pro-TAFI, TAFI and inactive carboxypeptidase U (TAFIi)] tended to decrease in both the patient groups (59.7 +/- 7.2 and 73.4 +/- 8.9% with and without microvascular complications, respectively) compared with controls (91.9 +/- 12.2%) (P = 0.12). We also assessed the overall hemostatic potential (OHP) in plasma, the clot lysis time and the overall fibrinolytic potential. The OHP was significantly higher in patients with complications compared with controls (8.9 +/- 0.9 versus 6.7 +/- 0.4; P < 0.05) and also higher in the diabetics without complications (7.8 +/- 0.6), although the latter difference did not reach statistical significance. Levels of clot lysis time and overall fibrinolytic potential were similar in the two groups of patients and the controls. The increased OHP in plasma from diabetic patients with microvascular complications indicates an imbalance of the hemostatic system towards a prothrombotic state. No signs of impaired fibrinolysis were observed in patients with diabetes. Using the OHP method for estimation of overall hemostasis, it seems that TAFI does not influence either fibrinolysis or the increased thrombotic potential observed in patients with type I diabetes mellitus.