Polycythemia Vera Overview
Polycythemia vera, also called “PV,” is a chronic blood disorder in which a person’s bone marrow (the spongy tissue located in the center of your bones) makes too many red blood cells (RBC). Sometimes, people with PV also make too many white blood cells and platelets, which are blood cells that help your body form clots to stop bleeding.
When there are too many blood cells in the body, the blood becomes thicker than normal. Since thicker blood flows more slowly, a person with PV is at risk of not getting sufficient oxygen to their organs, causing symptoms including headache, difficulty breathing, itchy skin, and bruising.
Serious side effects like stroke, heart attack, blood clots, or a pulmonary embolism (which is a blood clot in the lung) can also occur because the blood has difficulty moving through the vessels. With treatment, your risk of developing adverse symptoms and side effects is reduced.
Take a look at this animation to see how PV affects blood flow and red blood cell count:
To understand what causes PV, you need to first understand the JAK2 gene. Its main job is to create a protein that helps your bone marrow make blood cells. A change in the gene (called a mutation) leads to increased blood cell counts and causes PV.
Experts are not sure why some people develop the JAK2 mutation. While PV is not passed down from parent to child, research suggests that some people have a genetic vulnerability to developing PV. In other words, for some unknown reason, certain people are more likely than others to acquire the JAK2 mutation.
Treatment Options & Benefits
With the right approach to your care, you can successfully stall PV’s progression and increase your survival from six to 18 months to 13 years or more. Treatment can also help you manage symptoms, and it reduces your risk of developing complications and comorbidities (having two or more diseases at the same time) so you can maintain a better quality of life.
There are several categories of PV therapies available. Here are some of the most popular:
Each therapy is tailored to each individual, so not all options are right for everyone. Talk to your care team about what treatment options would be best for you.
In addition to taking your drugs as prescribed, things like eating a healthy diet, exercising, seeing your primary care provider for preventive health care, and managing cardiovascular factors like diabetes or obesity can help you live well with PV.
Talking To Your Doctor About Treatment
Having multiple PV treatment options available is an advantage, but it sometimes can be overwhelming to navigate all of them. Asking the right questions so you can understand why your care team recommends a specific drug over another, for example, is an empowering way to take part in your care.
If you’re not sure where to start the conversation, this doctor discussion guide can help. Download it for a refresher on PV-related vocabulary and use the commonly asked questions to learn as much as you can about living with polycythemia vera.
PV symptoms result primarily from an elevated red blood cell count. That said, a high number of platelets and white blood cells also play a role in certain symptoms and complications.
Click on the various body parts on the chart below to learn how PV may impact each:
Vision ChangesVision problems ranging from blurry or double vision to transient blindness may occur in PV. They are a result of delayed blood flow to the retina, since the blood of people with PV is thick and moves sluggishly and slowly.
If you or a loved one has PV and are experiencing vision changes, especially if you have transient blindness, be sure to contact your oncologist right away. Early treatment with therapies that reduce the number of red blood cells is important to prevent possible permanent eye damage.
It’s important to note that the course of PV is variable, meaning some people have a mild disease with few symptoms, while others have a more severe, debilitating disease. Those with few symptoms of PV are often only diagnosed incidentally, after a routine medical visit.
And while nonspecific symptoms like headache, dizziness, facial flushing, weakness, excessive sweating, and unusual tiredness are common, there are also specific symptoms to note, along with helpful strategies for managing them.
Common PV Symptoms, and How to Manage Them
I can’t tolerate hot baths or showers anymore—they make my skin feel incredibly itchy. Instead, I take cool showers, which helps. The weather, especially the heat, also really affects how I feel. As a result, I try to stay cool during the summers. I have rechargeable handheld fans in every handbag, and we invested in a portable air-conditioning unit for the bedroom. I also use silk bedding (it feels cooler) and try to wear only natural-fiber clothing, which is more breathable. I’ve spoken to other PV patients who say they’ve had similar success with their itching when they focus on staying cool.
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