Incidence of Aspirin Resistance and Its Relationship With Cardiovascular Risk Factors and Graft Function in Renal Transplant Recipients

Background. Aspirin (ASA) is frequently used to prevent cardiovascular events and improve renal graft function after renal transplantation. Clinical studies have demonstrated that decreased responsiveness to ASA therapy is associated with an increased risk of atherothrombotic events. However, no clinical trial to date has evaluated the incidence and clinical importance of ASA resistance among renal transplant recipients. Aim. To assess the incidence of ASA resistance and its association with cardiovascular risk factors (CRF) and renal graft function after renal transplantation. Methods. We prospectively included 40 patients undergoing living related donor renal transplantation using ASA (80 mg/d) in the study. ASA resistance was defined using a platelet function analyzer (PFA-100). Glomerular filtration rate (GFR) was measured by postoperative Tc-99m diethylenetriaminepentaacetic acid renal scintigraphy. We investigated the incidence of ASA resistance and its relationship to CRF and renal graft function. Results. ASA resistance was noted in 11 patients (27.5%). The demographic characteristics of the patients were similar in both groups (P >.05). Compared with patients in the ASA-sensitive group, patients in the ASA-resistant group showed significantly higher total cholesterol, low-density lipoprotein cholesterol, triglyceride, C-reactive protein, and fibrinogen levels and lower GFRs (44 +/- 21 mL/min vs 63 +/- 26 mL/min, P =.03). The incidence of ASA resistance was higher among patients with GFRs < 60 mL/min compared with those with a GFR >= 60 mL/min (10% vs 1%; P =.012). Conclusion. ASA resistance is associated with higher lipid levels and inflammatory and thrombotic cardiovascular risk factors and lower GFRs in renal transplant recipients.