From the Guidelines
Risk stratification for polycythemia vera is primarily based on age and history of thrombosis, with patients over 60 years old or those with a history of thrombosis considered high-risk, as recommended by the European LeukemiaNet 1 and supported by more recent guidelines 1.
Key Factors in Risk Stratification
- Age: Patients over 60 years old are considered high-risk
- History of thrombosis: Patients with a history of thrombosis are considered high-risk
- Cardiovascular risk factors: May be considered as additional risk modifiers, creating an intermediate risk category
- Leukocytosis and JAK2 V617F allele burden: May influence risk assessment, but are not part of the standard stratification
Treatment Decisions Based on Risk Stratification
- Low-risk patients: Typically receive low-dose aspirin (81-100 mg daily) and phlebotomy to maintain hematocrit below 45% 1
- High-risk patients: Require cytoreductive therapy (hydroxyurea, interferon-alpha, or ruxolitinib) in addition to aspirin and phlebotomy, with the goal of maintaining hematocrit below 45% 1
Importance of Risk Stratification
Risk stratification is essential in polycythemia vera as it helps balance the need to prevent thrombotic complications against the potential side effects of more aggressive treatments, ultimately improving patient outcomes in terms of morbidity, mortality, and quality of life 1.
From the Research
Risk Stratification for Polycythemia Vera
The risk stratification for polycythemia vera (PV) is based on several factors, including:
- Age: Patients aged 60 years or older are considered high-risk 2, 3, 4, 5
- History of thrombosis: Patients with a prior thrombosis are considered high-risk 2, 3, 4, 5
- Hematocrit levels: Elevated hematocrit levels are associated with an increased risk of thrombosis 2
- Leukocytosis: Elevated white blood cell count is associated with an increased risk of thrombosis 2, 3
- Cardiovascular risk factors: Patients with cardiovascular risk factors are at increased risk of arterial thrombosis 4
- JAK2 mutation: The presence of a JAK2 mutation is a diagnostic criterion for PV, but it is not a direct risk factor for thrombosis 4, 5
- Absolute neutrophil count: Higher absolute neutrophil count is associated with an increased risk of venous thrombosis 4
- JAK2V617F allele burden: Higher JAK2V617F allele burden is associated with an increased risk of venous thrombosis 4
Risk Categories
Patients with PV can be categorized into two risk groups:
- Low-risk: Patients under 60 years old with no history of thrombosis 2, 3, 4, 5
- High-risk: Patients 60 years or older and/or with a history of thrombosis 2, 3, 4, 5
Treatment Strategies
Treatment strategies for PV are based on the risk category: