Near-normal glycaemic control does not correct abnormal platelet reactivity in diabetes mellitus

The effect of improved glycaemic control, effected by 16 weeks continuous subcutaneous insulin infusion (CSII), on platelet aggregation and platelet prostaglandin biosynthesis has been assessed in a group of 11 diabetic patients with painful peripheral neuropathy. Before CSII and compared with results obtained on samples from age- and sex-matched control subjects, there was enhanced reactivity of the platelets from diabetic patients to ADP, collagen and sodium arachidonate (NaAA). There was also increased thromboxane B2 (TXB2) production after platelet stimulation by NaAA. In contrast, collagen-induced thromboxane production by platelets from diabetic patients was significantly less than that of platelets from controls. Treatment by CSII resulted in a statistically significant improvement in glycaemic control and this was maintained for the 16 week period of the study. At 16 weeks and in the presence of near-normal glycaemic control, the enhanced platelet reactivity in response to collagen and NaAA persisted and that to ADP was further increased. Collagen-induced thromboxane production was, however, corrected by CSII.