Analysis of thrombosis and bleeding complications in patients with polycythemia vera: a Turkish retrospective study

Abstract

The aims of this study are to determine the incidence and risk factors of thrombosis and bleeding in polycythemia vera (PV) patients and to research the effects of these risk factors on survival. The medical records of 155 PV patients were analyzed retrospectively. Patients were divided into groups according to whether or not thrombosis had developed in follow-up, and according to whether or not bleeding had occurred during follow-up. The mean age at diagnosis was 53 years, and the mean follow-up period was 66 months. The percentage of cases in which thrombosis events had occurred before diagnosis and during follow-up were 26 and 28 %, respectively. Comparisons of disease duration and average thrombosis risk score between groups with or without thrombosis drew statistically significant results. A patient's history of thrombosis and thrombocytosis at first visit was found to have a significant effect on thrombosis recurrence. The major bleeding rate was 8 %. Post-PV myelofibrosis was an independent risk factor for bleeding. The major cause of death among the patients in this study was primary thrombosis. The most important causes of mortality among PV patients are thrombosis, and the most prominent risk factors for thrombosis development are disease duration and high thrombosis risk scores. Thrombocytosis in patients with a history of thrombosis may cause thrombosis recurrence during the follow-up period.

Hemorrhage in Essential Thrombocythemia or Polycythemia Vera: Epidemiology, Location, Risk Factors, and Lessons Learned from the Literature

“…31,37 Leukocyte counts were identified as risk factors in three out of 10 studies but with various thresholds. [15][16][17]21,22,33,[36][37][38]47 This risk seemed higher when leukocyte counts increased (>11 G/L, HR ¼ 1.9 or 1.74 15,37 ; >16 G/L, OR ¼ 3.19 16 ). Baseline complete blood count Platelets 15-17,20,22,31,33,36-38,47 6 20,22,31,33,36,37 Positive thresholds tested (if detailed): >800 G/L 36 (IRR ¼ 10.6 (1.7-69), 36 >1,000 G/L 22,31,37 A nonlinear increase of HR once platelets >450 G/L 38 Negative threshold used: >1,000 G/L and <100 G/L, 23 and >1,000 G/L þ CALR mutation 39 Positive threshold used: >1,000 G/L þ JAK2 mutation 39 24,39 Positive for JAK2þ ET, 24 and JAK2þ ET plus platelets >1,000 G/L 39 : IRR ¼ 9.8 (2.3-42.3) 39 Negative if analyzed alone [15][16][17][18]36,37 or associated with antiplatelets 36…”

“…16,24,43 Twenty-one lethal bleeding events of PV patients were individualized in this review. 3,13,16,17,43,[45][46][47] Locations were the CNS in four cases (19%), the GIT in one (4.8%) 43,45,46 , "other" in five cases (23.8%), 46 and undetailed in all other cases.…”

“…16 Seven studies, including three randomized comparative studies, [43][44][45] focused only on PV, with cohorts ranging from 155 to 1,638 patients, and a median follow-up ranging from 1.6 to 16.3 years. 3,[43][44][45][46][47][48] In the PV literature, a total of 5,683 patients were followed for a median time of 4.8 years (►Table 2). The incidence rate of MB events ranged from 0.3 to 5.3 per 100 patient-years.…”

“…30,32,35 Most importantly, the case fatality rate of MB ranged from 3.1 to 26.7% of cases. 3,30,32,35,37,46,47 In total, 20.6% (35/170) of MB events led to death. Abbreviations: FU, follow-up; pts/y, patients/year; n, number of patients; ND, not detailed; PV, polycythemia vera.…”

“…16,20,23,37 Lastly, male gender was once found to be a bleeding risk factor with a relatively high OR of 3.74, 33 but there was no significant impact of gender on bleeding risk in six other analyses. [15][16][17]20,36,47 Fig. 2 Location of any bleeding and specifically major bleeding event in PV and ET patients in the literature.…”