What is Polycythemia Vera

Polycythemia Vera is a rare, chronic blood cancer categorized as a myeloproliferative neoplasm where the bone marrow produces too many red blood cells. This overproduction thickens the blood, significantly increasing the risk of serious complications like blood clots, stroke, and heart attack.

What exactly is Polycythemia Vera?

In Polycythemia Vera, the bone marrow functions incorrectly, leading to an uncontrolled production of red blood cells, and often white blood cells and platelets. This "hyperviscosity" or thickening of the blood makes it move more slowly through the circulatory system, which can cause poor oxygen delivery to tissues and blockages in blood vessels. Currently, 118 members of the DiseaseMaps community are living with Polycythemia Vera and sharing their experiences with this condition.

What causes Polycythemia Vera?

The primary driver of Polycythemia Vera is an acquired genetic mutation—most commonly the JAK2 V617F mutation—which acts like a "stuck gas pedal" for blood cell production. Unlike hereditary conditions, this mutation typically occurs during a person's lifetime and is not passed down from parents to children. Key clinical characteristics include:

• Increased Hematocrit: A high percentage of red blood cells in the blood volume.


• Low Erythropoietin (EPO) levels: The body tries to compensate for the overproduction by lowering the hormone that usually stimulates red blood cell growth.


• Splenomegaly: An enlarged spleen, caused by the organ working overtime to filter the excess blood cells.

Who is typically affected by Polycythemia Vera?

Polycythemia Vera is considered a rare disease, with an estimated prevalence of 44 to 57 cases per 100,000 people. While it can occur at any age, the median age at diagnosis is approximately 60 to 65 years. It affects men slightly more frequently than women, and there is no strong evidence suggesting that geographical location or ethnicity significantly alters the risk of developing this condition.

How does it differ from other blood disorders?

Unlike secondary polycythemia, where red blood cell production increases due to external factors like smoking or living at high altitudes, Polycythemia Vera is a primary bone marrow disorder. It is distinct from other blood cancers because it is a chronic condition that can often be managed for many years with targeted therapies and regular monitoring.

Next steps

• Consult a hematologist or an oncologist specializing in myeloproliferative neoplasms.


• Request a JAK2 mutation test to confirm the clinical diagnosis.


• Connect with the 118 peers on DiseaseMaps.org to share management strategies.


• Discuss with your physician whether low-dose aspirin or phlebotomy is appropriate for your specific blood count levels.

Medical disclaimer: This information is for educational purposes only and does not constitute professional medical advice, diagnosis, or treatment; always seek the advice of your physician regarding a medical condition.

References

• NIH Genetic and Rare Diseases Information Center (GARD): Polycythemia Vera.


• Orphanet: Rare Disease Database (ORPHA: 732).


• National Organization for Rare Disorders (NORD): Polycythemia Vera.


• OMIM (Online Mendelian Inheritance in Man): Entry #263300.