Abstract Rationale Essential Thrombocythemia (ET) is a common classical myeloproliferative neoplasms (MPN), with an annual incidence of approximately 1.5/100,000. Pulmonary Hypertension (PH) is known to complicate MPN and is prevalent in ET patients with estimates exceeding 50%. Patients with ET have an excellent prognosis, particularly if diagnosed at a younger age, but the morbidity and mortality associated with secondary PH in ET remains largely unknown. To address this gap, we investigated the impact of PH risk on survival of patients with ET from a large single center cohort. Methods In this retrospective study, we identified the cohort of ET patients at the Silver MPN Center of Weill Cornell Medicine who had transthoracic echocardiography (ECHO). PH risk was established based on tricuspid regurgitation jet calculation utilizing cutoffs of 2.8 m/s and 3.4 m/s for mild PH risk and high PH risk. Survival was modeled using Kaplan Meier estimates and Cox Proportional Hazard Models. Results In total, 110 ET patients with an echo were included for analysis. The prevalence of any increased PH risk and high PH risk in this ET cohort was 16% and 6.4% respectively. Median age at echo was 65 years old while the median duration of MPN disease prior to echo was 4.4 years. Median survival for PH risk patients was 13 years and was not reached for the low PH risk group. (p = 0.007). Progression free survival and thrombosis free survival were not significantly shorter in patients with increased PH risk compared to low PH risk. When stratified by driver mutation, median survival was significantly shorter among JAK2 and CALR ET mutants with PH risk compared to low PH risk (p = 0.008, p = 0.0002). Cox proportional hazard model demonstrated a 1.5x increased risk for death among those with PH risk, and a 1.8x risk of death among JAK2+ mutants with PH risk in our multivariable model but these effects were not statistically significant. There was a signal toward increased probability of increased PH risk with JAK2 mutation (OR = 2.5 95% CI 0.61-17). Conclusions In a cohort of ET patients, increased PH risk was associated with worse survival compared to normal PH risk among all subjects in the cohort. These data may clarify a mechanistic pathway to PH in myeloproliferative neoplasms and may inform potential advanced PH therapies in this patient population but require more data to reach a more robust conclusion. This abstract is funded by: None
Gazda et al. (Fri,) studied this question.