Inhibition of Platelet Function by Aspirin in Insulin Dependent Diabetics without Vascular Disease.

Abstract 4172

Diseases like diabetes that are associated with increased platelet production are reported to have decrease aspirin (ASA) induced platelet inhibition. ASA inhibition of platelet function is mediated via acetylation of platelet cylooxygenase, which is completed approximately 30 minutes after ingestion. Thereafter production of new non-acetylated platelets increases the proportion of normal platelets gradually reversing ASA platelet inhibition. We tested the hypothesis that insulin dependent diabetics (type 1) without clinical evidence of occlusive vascular disease have less aspirin platelet inhibition than normal controls. The amount of ASA (325mg) platelet inhibition was measured using the slope (S) of platelet prostaglandin agonist (PPA) stimulated light aggregation curve that decreases after ASA. Aggregation was measured at 3 time points: before ASA ingestion, time 0 (T₀); 2 hours post ASA (T₂); and 24 hours after ASA (T₂₄). Percent recovery from aspirin inhibition was calculated using the formula (T₂₄–T₂)/ (T₀-T₂) x100. Eight adult insulin dependent diabetic patients without clinical evidence of vascular disease and who were not taking aspirin were compared with 11 nondiabetic controls. 24 hours after aspirin ingestion diabetic patients recovered 10% of their maximal ASA platelet inhibition compared to 13% in controls (p=0.69). We conclude that recovery of platelet function from ASA in insulin dependent diabetics without clinical vascular disease occurs at the same rate as normal controls, suggesting that the previously reported decrease in platelet inhibition in diabetic patients may be related to increased platelet production associated with clinically evident occlusive vascular disease.