Prolonged Proton Pump Inhibitor Use and Thrombohemorrhagic Risk in Essential Thrombocythemia and Polycythemia Vera Patients Treated with Long-Term Aspirin: A Pilot Study.

INTRODUCTION: Proton pump inhibitors (PPIs) are known to decrease the risk of gastrointestinal (GI) bleeding. However, concerns have been raised regarding the potential pharmacodynamic interactions of PPIs and antiplatelet drugs with respect to cardiovascular risk. Patients with BCR::ABL1-negative myeloproliferative neoplasms (MPNs), essential thrombocythemia (ET), and polycythemia vera (PV) often suffer from peptic ulcer disease (PUD) and frequently receive low-dose aspirin due to an intrinsically high thrombotic risk. METHOD: This retrospective multicenter study from a community setting investigated whether continuous PPI use may affect thrombohemorrhagic risk in ET and PV patients treated with long-term aspirin. RESULTS: Ninety-four aspirin-treated MPN patients (ET = 36, PV = 58) were included; median age was 69.5 years (range 21-92) and 40 (42.6%) were males. Nineteen (20.2%) patients continuously received PPIs and pantoprazole (n = 15, 78.9%) was the most frequently received PPI. PV phenotype (p = 0.085), male sex (p = 0.011), and prior thrombosis (p = 0.005) were associated with PPI use, whereas no correlations were found with respect to age, disease risk, splenomegaly, mutational status, constitutional symptoms, cardiovascular risk factors, cytoreductive treatment, or any of the blood cell counts (p > 0.050 for all analyses). The median follow-up time was 55.5 months; 19 (20.2%) thrombotic and 13 (13.8%) bleeding events occurred during this time. The use of PPIs was not associated with an increased risk of thrombosis (p = 0.158) or overall bleeding (p = 0.229) and none of the patients treated with PPIs experienced GI bleeding. CONCLUSIONS: Considering that Helicobacter pylori infection and PUD are quite frequent in ET and PV patients, these preliminary results may provide some reassurance to physicians regarding the absence of thrombohemorrhagic risk associated with prolonged PPI use in MPN patients treated with long-term aspirin. Our observations may be even more important in the light of recent evidence suggesting suboptimal platelet inhibition in ET with once-daily when compared to twice- or triple-daily aspirin which may also cause more abdominal discomfort. Limitations of this study are its retrospective design, limited number of patients included, and the lack of pharmacodynamic and pharmacokinetic assessments.

Higher estimated plasma volume status is associated with increased thrombotic risk and impaired survival in patients with primary myelofibrosis.

Introduction: Blood plasma represents a large reservoir of cytokines and other mediators of inflammation. Higher estimated plasma volume status (ePVS) has been shown to correlate with increased thrombotic risk in polycythemia vera patients, but its clinical and prognostic associations in patients with myelofibrosis are unknown which we aim to evaluate in this study. Materials and methods: We retrospectively analysed a multicentric cohort of 238 patients with primary (PMF) and secondary myelofibrosis (SMF). Estimated plasma volume status was calculated using the Strauss-derived Duarte formula. Overall survival (OS) and time to thrombosis (TTT) considering both arterial and venous thromboses were primary endpoints of interest. Results: Median ePVS was 5.8 dL/g and it did not significantly differ between PMF and SMF patients. Patients with more advanced disease features, more pronounced inflammation and higher comorbidity burden had higher ePVS. Higher ePVS (> 5.6 dL/g) was associated with shorter OS in PMF (unadjusted hazard ratio, HR = 2.8, 95% confidence interval, CI (1.79-4.41), P < 0.001) and SMF (unadjusted HR = 2.55, 95% CI (1.1-5.71), P =0.025) and with shorter TTT in PMF (> 7 dL/g, unadjusted HR = 4.1, 95% CI (1.44-11.59), P = 0.009) patients. Associations with OS diminished in multivariate analyses after adjustments for the dynamic-international-prognostic-scoring-system (DIPSS) and myelofibrosis-secondary-to-PV-and ET-prognostic-model (MYSEC-PM), respectively. Association with TTT remained significant independently of JAK2 mutation, white blood cell count and chronic kidney disease. Conclusions: Myelofibrosis patients with more advanced disease features and more pronounced inflammation have higher ePVS, indicative of expanded plasma volume. Higher ePVS is associated with impaired survival in PMF and SMF and higher thrombotic risk in PMF patients.