Good morning, @mags17 Polycythemia Vera is a blood condition where too many red blood cells are produced in the body. It’s generally caused by the acquired mutation in the JAK2 gene which can cause other blood conditions as well such as too many platelets. But there can also a link between sleep apnea and an elevated amount of red blood cells/hematocrit. When my RBC numbers started to climb for no reason, my doctor had asked if I have sleep apnea and ordered a test find out of that was the cause.

Here’s a great article on issues which can develop with sleep apnea
https://sleepation.com/the-relationship-between-sleep-apnea-and-high-red-blood-cell-count/
~From the Mayo website: Possible reasons for High RBC https://www.mayoclinic.org/symptoms/high-red-blood-cell-count/basics/causes/sym-20050858

You had an interesting discovery between your PV blood numbers and the change that came about in your sleeping pattern where you had better nights when you were elevated a little. I’m sorry you didn’t get a better answer than what the doctor’s assistant gave you. Yes, you have the gene but that may not be the entire story!

What you could do is ask your hematologist or GP for an overnight oximetry test. It’s simple and inexpensive, and should be paid for by insurance or medicare. It’s the same little gadget that is placed over your finger when you have a checkup. Only this one stays on overnight and has a link to a bracelet you where that records the numbers. My test last year was around $100. Also, since you had remarkably better blood numbers and better sleep, maybe continuing to elevate your upper body will help long term. It too a referral to the cardiac health unit at my hospital. Just had to stop in and pick up the kit, then return it the next day.

However, you were found to have the acquired JAK2 mutation which is common in the development of Polycythemia Vera. Your doctor is using this important factor to diagnosis your PV. But, it’s entirely possible to have both factors, the lack of oxygen from apnea and the JAK2 mutation playing into your diagnosis for PV.

From my understanding, blood conditions can take years to develop so even if someone has the JAK2 mutation, they may not see symptoms progress for some time. So in your case, even though you have the mutation which can cause PV, you may have developed the excess red cells, not because of the mutation yet, but because of the lack of oxygen at this time. It’s an interesting parallel you discovered between your change in sleep pattern while not taking the HU for a couple months.

The JAK2 mutation can bring about a change in bone marrow producing a condition referred to as myeloproliferative neoplasms where the bone marrow makes too many blood cells.
You might find this article helpful in understanding the JAK2 mutation.
https://www.verywellhealth.com/jak2-mutation-5217909
Even if your PV wasn’t caused by sleep apnea it certainly can create other issues as seen in the article I posted for you. It would be important to find out if you have it. Are you continuing to sleep elevated?