What is a common complication of polycythemia vera?

• A. Hypotension.
• B. Thrombosis.
• C. Edema.
• D. Anemia.

Answer: (B)

Polycythemia vera thickens the blood because there are too many red blood cells, which raises blood viscosity and slows flow through vessels. This hyperviscosity makes clot formation more likely in arteries and veins, so thrombosis becomes a common and serious complication. Clots can lead to events like stroke, deep vein thrombosis, or heart attack, driving much of the disease’s morbidity unless the hematocrit and platelet activity are controlled. Treatments such as phlebotomy to reduce red cell mass and low-dose aspirin to reduce clotting risk are used to prevent these thrombotic complications. While hypotension, edema, or anemia can occur in various contexts, they are not the hallmark complications of polycythemia vera.