Hematocrit level influences platelet adhesion in polycythemia vera
Recently, a novel mechanism was described by which elevated hematocrit can lead to an increased risk of thrombosis. The erythrocytes push the platelets closer to the vessel wall, increasing the probability of their adhesion and activation via von Willebrand factor and collagen.1
This may occur in polycythemia vera (PV), where multiple cellular events are needed to trigger thrombosis. Dr. Sara Gamba (ASST Papa Giovanni XIII, Bergamo, Italy) presented data from a cohort of 52 PV patients, demonstrating that elevated hematocrit significantly correlated with platelet adhesion to the vessel wall.
“This is likely favored by rheological factors coming from the increased red blood cell count typical of this disease. Our findings indicate that elevated hematocrit is a relevant thrombotic mechanism in PV.”
- Walton BL, et al. Blood 2017;129:2537-46