Platelet FcγRIIA Receptor Surface Expression Is Increased in Patients With ESRD and Is Associated With Atherosclerotic Cardiovascular Events

Background: Accelerated atherogenesis is a prominent feature of end-stage renal disease (ESRD). Methods: Expression of platelet FcγRIIA immunoglobulin G receptor (FcγR) was measured in 2 populations: (1) 48 patients with ESRD with a mean age of 50.7 ± 2.3 (SEM) years and (2) 48 healthy age- and sex-matched controls aged 53.6 ± 1.6 years. Results: Platelet FcγR expression was enhanced significantly in patients with ESRD (mean fluorescence intensity [MFI], 7.88 ± 0.42 [SEM]; 95% confidence interval [CI], 7.03 to 8.72 versus 5.07 ± 0.21; 95% CI, 4.64 to 5.49; P < 0.0001). In patients with ESRD, multivariate analysis showed that hemoglobin level and diastolic blood pressure were related inversely to FCγR expression (P = 0.01 and P = 0.03, respectively). Atherosclerotic cardiovascular events (ACVEs) were recorded prospectively for the ESRD cohort. A total of 22 ACVEs, defined as the occurrence of myocardial infarction (10 events), cerebrovascular accident (7 events), and/or a peripheral vascular event (5 events), were observed. In the group with greater receptor expression (MFI > 7.785; n = 24), 13 of 17 patients (76.5%) experienced at least 1 ACVE, whereas only 4 of 17 patients (23.5%) with low FcγR expression (MFI < 7.785; n = 24) experienced an event (P = 0.007). Conclusion: (1) Uremia is associated with enhanced platelet FcγR expression, and (2) patients with greater platelet FcγR expression are significantly more likely to experience ACVEs; however, (3) the small sample size is a limitation and our work therefore is a hypothesis-generating pilot study that remains to be confirmed.