Which laboratory finding is typically elevated in polycythemia vera?

In polycythemia vera, a myeloproliferative neoplasm, there is an overproduction of red blood cells, which leads to elevated hemoglobin and hematocrit levels. This condition is characterized by increased blood viscosity due to the high concentration of red blood cells, resulting in symptoms such as headaches, dizziness, and an increased risk of thrombosis. Hemoglobin is the protein in red blood cells that carries oxygen, and hematocrit is the proportion of blood volume that contains red blood cells. Therefore, the hallmark laboratory findings in polycythemia vera are consistently increased levels of both hemoglobin and hematocrit, distinguishing it from other hematological conditions.