Abstract 11420: Platelet Activity Mediates Increased Cardiovascular Risk in Patients with End-Stage Kidney Disease and Peripheral Artery Disease

Abstract

Background: End-stage kidney disease (ESKD) and peripheral artery disease (PAD) are frequently co-prevalent and each associated with increased cardiovascular (CV) risk. Platelets drive PAD pathogenesis and mediate atherothrombosis. Their function and influence on CV risk in ESKD remain unclear. We hypothesized that ESKD is associated with heightened platelet activity and incident cardiac and limb events in patients with PAD. Methods: The Platelet Activity and Cardiovascular Events study enrolled 289 patients with PAD undergoing lower extremity revascularization (LER). We measured platelet activity prior to LER via light transmission aggregometry in response to submaximal ADP, collagen, serotonin, epinephrine, and arachidonic acid. We followed patients for a median of 18 months for a primary endpoint of major adverse CV event (MACE; MI, stroke, death) and a secondary composite of major adverse CV or limb event (MACLE; MACE or acute limb ischemia). Results: Among enrolled subjects, 25 (9%) had ESKD. They were younger and more likely to have a history of coronary artery disease (CAD), heart failure, and critical limb ischemia (CLI) than those without ESKD (P<0.05 for each). Aggregation in response to epinephrine 2.0 uM after 5 minutes and at maximum was greater in those with compared to without ESKD (61% vs. 48%; P=0.004 and 77% vs. 60%; P=0.001, respectively). After multivariable adjustment, patients with vs. without ESKD were at greater risk for CV events ( Figure ). Platelet aggregation in response to submaximal epinephrine stimulation had a 32% and 45% mediating effect on the excess risk for MACE and MACLE, respectively, associated with ESKD ( Figure ). Conclusions: In patients with PAD, ESKD was associated with increased platelet aggregation in response to submaximal epinephrine that partially mediated increased risk for incident cardiac and limb events. Platelet activity appears to be an important mechanism underlying CV risk in ESKD.