Correlation Between PAI-1 Gene 4G/5G Polymorphism and the Risk of Thrombosis in Ph Chromosome-Negative Myeloproliferative Neoplasms

Thrombosis has been recognized as one of the most significant risk factors of high mortality and disability in patients with Philadelphia (Ph) chromosome negative myeloproliferative neoplasms (MPNs). However, the risk factors of thrombotic events in these patients have not been completely understood. In this study, the clinical data of 58 patients with Ph-MPNs were obtained and analyzed, including 34 cases of essential thrombocytopenia (ET), 23 thrombotic events happened in 21 (36%) patients, among which 60% (14 of 23) with cerebral infarction, 17% (4 of 23) with coronary heart disease and 23% (5 of 23) with venous thrombosis. There were no significant differences in age, sex, and blood cell count between polycythemia vera (PV) and ET patients who have experienced thrombotic events and those who have not. In ET patients, the incidence of thrombotic events in plasminogen activator inhibitor-1 (PAI-1) genotype 4G4G was significantly higher than that in genotype 4G5G and genotype 5G5G (P < .05). The incidence of thrombotic events in PV and ET patients with infection was higher than those without infection (P < .05). Using logistic regression analysis, we found that PAI-1 genotype 4G4G and infection were associated with thrombotic events (odds ratio 6.744, 95% CI: 1.195-38.056 and 15.641 95% CI: 3.327-73.522). The 4G/4G polymorphism of PAI-1 gene and infection are independent risk factors of thrombotic events in patients with Ph-MPNs. PAI-1 gene 4G4G and infection in ET and PV patients with Janus kinase 2 (JAK2) V617F mutation were shown to be high risk of thrombotic events. Therefore, clinical doctors should put more attention on PAI-1 genotype 4G4G and infection in JAK2 V617F mutated patients with Ph-MPNs to prevent the thrombosis.