Rethinking Hematocrit as the Sole Target

In this segment the panel challenges the long standing focus on maintaining hematocrit below forty five percent as the sole marker of disease control. While hematocrit reduction remains essential for lowering thrombotic risk, the experts note that many patients spend substantial time above this threshold due to intermittent monitoring and reactive phlebotomy schedules. They emphasize that this approach inherently allows periods of suboptimal control. In addition, focusing exclusively on hematocrit overlooks other contributors to disease burden, including leukocytosis, thrombocytosis, and persistent symptoms. Faculty discuss emerging data suggesting that symptom control and functional status should be incorporated into treatment goals. They also highlight limitations of current monitoring strategies and speculate on future technologies that could allow more continuous assessment of hemoglobin or hematocrit levels. Importantly, the discussion reinforces that clinicians treat patients rather than laboratory values. A patient may meet numeric targets yet continue to experience debilitating fatigue or cognitive impairment, signaling inadequate disease control. The panel advocates for a broader framework that integrates hematologic parameters with patient reported outcomes and daily functioning. Such an approach may better reflect real world disease impact and guide more meaningful treatment decisions.