Monitoring of Aspirin Therapy in Patients with Cerebrovascular Pathology

Abstract

Aim. Evaluation of various methods for determining the effectiveness of aspirin therapy and aspirin resistance in patients with cerebrovascular disease (CVD) depending on the presence of type 2 diabetes mellitus (T2DM).Materials and methods. The prospective study included 78 patients with various manifestations of CVD. All patients received acetylsalicylic acid (ASA) 75 mg daily. Along with a comprehensive clinical examination, a laboratory assessment of platelet function with the usage of Born method with aggregometer, a detailed biochemical blood test (including the determination of the small subunit of low density lipoprotein [s-LDL]), as well as therapeutic drug monitoring of salicylates were performed on a gas chromatograph-mass spectrometer.Results. In 53% of cases, the absence or insufficiency of the effect of ASA on platelet aggregation was noted. Two subgroups were separately identified: with T2DM; (n=40) and without T2DM (n=38). Insufficient effect of the drug on platelet aggregation characteristics were observed in 65% of patients with T2DM and in 38% without T2DM. The differences were revealed between the groups in triglycerides, s-LDL, glycemic and glycated hemoglobin (p <0.05). In the group of patients with T2DM, the median ASA concentration was 0.01 [0; 0.32] μg/ml, and salicylic acid (SA)– 0.20 [0; 0.39] μg/ml, while in patients without T2DM higher values were noted: ASA 0.29 [0.15; 0.55] μg/ml, SA – 0.33 [0.05; 0.73] μg/ml. A decrease in the concentration of ASA was associated with an increase in the level of ADP-induced platelet aggregation. There was an increase in the levels of ADPand adrenaline-induced platelet aggregation with a decrease in the concentration of ASA (p=0.004) and SA (p=0.006). Therapeutic drug monitoring revealed a more significant decrease in ASA level in T2DM than in the comparison group (p=0.025).Conclusion. It is advisable to monitor aspirin therapy both with the assessment of platelet aggregation and with therapeutic drug monitoring. The relationship between the level of ASA and SA in the blood plasma and the functional activity of platelets was confirmed. The presence of T2DM is associated with a decrease in the concentration of ASA and aspirin resistance detected in therapeutic drug monitoring.