Incidence of Medical Conditions Associated with Polycythemia Vera Treatments
Authors: Chien Hung-Lun , Howe Andrew , Zimmerman Craig , Castro Claudia , Qin Albert , Geller Robert 
Published: December 2024

Introduction
Various medical conditions (MCs) and potential adverse events (AEs) have been reported in clinical trials among patients with polycythemia vera (PV) while on therapy. In the real-world setting, MC's may also be associated with certain lines of therapy (LOTs), patient demographics, and pre-existing conditions. We conducted a retrospective study to investigate AEs with treatment options for patients with PV.
Method
We utilized the IntegraConnect electronic health record (EHR) data for the analysis, which included 30,595 PV patients treated between 1998 and Feb/2024. Patients with their earliest diagnosis of PV in and after 2016 were included in the study. Patients previously diagnosed with myelofibrosis and acute myeloid leukemia were excluded from analysis. The treatments were hydroxyurea (HU), ruxolitinib (Rux), ropeginterferon alfa-2b-njft (ropeg), other interferons (Interferon), and phlebotomy only (PHL). Treatment duration shorter than 180 days were excluded in the analysis.
MCs and AEs were extracted from EHR system and practice management records and categorized into 11 categories: cytopenia (anemia, thrombocytopenia, leukopenia, neutropenia), pain, cardiac (hypertension, atrial fibrillation, cardiac arrhythmia, cardiotoxicity, and cardiac arrest), dehydration, CNS/mood (fatigue, depression, insomnia, headache, anxiety, dizziness), GI (appetite, nausea, abdominal pain, diarrhea, early satiety), respiratory (dyspnea, cough, respiratory failure), abnormal BMI, DVT/PE, organ disfunction (transaminitis, enlarge spleen, eye disorder), and skin disorders (pruritus, alopecia). To adjust for LOT and existing MCs which occurred within 180 days prior treatments were evaluated in the analysis. Descriptive analyses were conducted for the rate of MCs for each treatment. A difference in difference general estimating equation regression model was conducted to obtain adjusted statistics. Patient characteristics include age, gender, race, provider specialty, risk of thrombotic events, and LOT were adjusted in the model.
Result
After applying population selection criteria, 3,731 PV patients and 4,038 treatments were included. The average age at treatment was 67.2 years (SD=12.7; Median=69), 2,089 (56.0%) were male, and 2,871 (76.95%) were high risk patients. Of the 3,731 PV patients, 49.2% (n=1,837) were treated with HU, 41.2% (n=1,537) with PHL, 15.7% (n=585) with Rux, 1.2% (n=44) with Ropeg, and 0.9% (n=35) with Interferon.
Cytopenia was the top medical condition prior to and during treatment. The percentages for PHL patients was 20.7% and 50.9%, respectfully. For cytoreductive treatment (CT), the percentages were 26.7% and 71.1% for HU, 51.8% and 83.9% for Rux, 54.3% and 88.6% for interferon, and 45.4% and 79.5% for ropeg. Interferon patients (80%) experienced pain during treatment, which was higher than other treatments (HU: 47.4%, PHL: 41.8%, ropeg: 45.5%, Rux: 59.5%). For cardiac conditions, interferon and ropeg had decreased incidences during treatment (prior to treatment vs. during treatment: interferon: 17.1% vs.14.3%; ropeg: 4.5% vs. 2.3%), while HU, PHL, and Rux had increased incidences (prior to treatment vs. during treatment: HU: 11.7% vs. 19.7%, PHL: 9.2% vs. 17.5%, rux: 17.1% vs. 29.1%). Organ disfunction and CNS/mood MCs were higher during interferon treatment (45.7% and 45.7%), when compared to other treatments: ropeg (31.8% and 13.6%), rux (29.7% and 37.3%), HU (14% and 22.3%), and PHL (18% and 22.3%).
After adjustment, HU treatment was associated with an increased odds of cytopenias (OR=1.72, 95%CI=1.44-2.06) when compared to PHL. Interferon patients showed a decreased odds in cardiac (OR=0.38, 95%CI=0.23-0.62), respiratory conditions (OR=0.14, 95%CI=0.03-0.78), and abnormal BMI (OR=0.19, 95%CI=0.05-0.70) with compared to PHL. Ropeg patients showed lower odds than PHL patients in cardiac (OR=0.25, 95%CI=0.08-0.79), pain (OR=0.49, 95%CI=0.25-0.96), and DVT/PE (OR=0.57, 95%CI=0.42-0.78).
Conclusion
Various MCs were associated with different treatments among patients with PV. Proper management of MCs may improve patient compliance to treatment as well as patient outcomes. Further research will help develop best treatment and management for patients with PV.