Expert Insights

Assessing PV in Men and Women

Read transcript Close transcript

The reason that I differentiate women with polycythemia from men with polycythemia is that under normal circumstances, women have a smaller blood volume than men do. And if you use the male hematocrit for a female with polycythemia vera, then you are essentially allowing the female patient to have a larger blood volume than a normal woman would have. So this is just common sense physiology. So, if you come back to where we find most patients with polycythemia vera these days, we sort of diagnose them early because people tend to go to doctors more frequently and we have tests that we apply across the board, you know, in terms of complete blood counts. So people are picked up earlier and their hematocrits aren’t as high, so this—the idea of seeing someone with hematocrit of 55 or 60%—which should always be a red light, isn’t usually there. And so you will see women coming in with hematocrit of 48% or 46%. But a normal female hematocrit begins at 36 and sort of goes up and sort of ends about 42%. So, if you leave them at 45% or higher, you’re not completely treating them.

head shot of Dr Spivak
Jerry Spivak, MD Professor of Medicine and Oncology Director Center for the Chronic Myeloproliferative Disorders Johns Hopkins University School of Medicine | Baltimore, MD
Dr Jerry Spivak is a researcher and professor of medicine and oncology at Johns Hopkins University School of Medicine. He has served as a member and director on multiple boards, including the International Society of Hematology, and has been published in over 230 scientific and clinical journals. Among the awards Dr Spivak has received are a Research Career Development Award and a Merit Award from the National Institutes of Health.