Cardiovascular risk in polycythemia vera: Thrombotic risk and survival: Can cytoreductive therapy be useful in patients with low-risk polycythemia vera with cardiovascular risk factors?

Background/Aims: Cardiovascular risk factors are not considered in the current scores for evaluation of the thrombotic risk in myeloproliferative neoplasms, and in polycythemia vera (PV) in particular. Cytoreduction is currently not indicated in low-risk patients with PV, despite the absence or presence of cardiovascular risk factors. Our purpose is to highlight how cardiovascular risk factors in patients with PV increase the thrombotic risk both in low- and high-risk patients. Methods: We collected and analyzed data from 165 consecutive patients with a diagnosis of PV followed at our institution and compared the frequency of thrombosis in subgroups of patients distinguished by the presence or absence of cardiovascular risk factors. The statistic tools used to obtain the results were the χ and the Kruskal-Wallis test for frequencies, and the Kaplan-Meyer method as well as the log-rank test for analysis of survival data. Results: The major result obtained is that the frequency of thrombotic events in our population is strictly linked with the cardiovascular risk, and it increases with the number of risk factors. Moreover, survival significantly worsens with the number of cardiovascular risk factors, despite the classical PV risk stratification. Conclusion: It should be useful to design perspective studies to determine the real influence of cardiovascular risk factors on the thrombotic risk for patients with PV and on survival in order to evaluate the opportunity to develop new specific therapeutic recommendations.