There are unresolved questions regarding the association between persistent leukocytosis and risk of thrombosis and disease evolution in polycythemia vera (PV), as much of the published literature on the topic does not appropriately utilize repeated measures data or time-dependent modeling to answer these questions. To address this knowledge gap, we analyzed a retrospective database of 520 PV patients seen at 10 academic institutions across the United States. Taking hematologic lab data at approximate 3-month intervals (or as available) for all patients for duration of follow-up, we used group-based trajectory modeling (GBTM) to identify latent clusters of patients who follow distinct trajectories with regards to their leukocyte, hematocrit, and platelet counts over time. We then tested the association between trajectory membership and hazard of two major outcomes: thrombosis and disease evolution to myelofibrosis, myelodysplastic syndrome, or acute myeloid leukemia. Controlling for relevant covariates, we found that persistently elevated leukocyte trajectories were not associated with hazard of thrombotic event (p = 0.4163), but were significantly associated with increased hazard of disease evolution in an ascending stepwise manner (overall p = 0.0002). Additionally, we found that neither hematocrit nor platelet count were significantly associated with hazard of thrombosis or disease evolution.

中文翻译：

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真性红细胞增多症中持续的白细胞增多与疾病演变有关，但与血栓形成无关。

关于持续性白细胞增多症与真性红细胞增多症 (PV) 的血栓形成风险和疾病演变之间的关联存在未解决的问题，因为许多已发表的关于该主题的文献没有适当地利用重复测量数据或时间依赖模型来回答这些问题。为了解决这一知识差距，我们分析了在美国 10 个学术机构就诊的 520 名 PV 患者的回顾性数据库。在随访期间，每隔大约 3 个月（或可用）为所有患者获取血液学实验室数据，我们使用基于组的轨迹建模 (GBTM) 来识别潜在的患者群，这些患者在白细胞方面遵循不同的轨迹、血细胞比容和血小板计数随着时间的推移。然后，我们测试了轨迹成员与两个主要结果的风险之间的关联：血栓形成和疾病演变为骨髓纤维化、骨髓增生异常综合征或急性髓系白血病。控制相关协变量，我们发现持续升高的白细胞轨迹与血栓形成事件的风险无关（p = 0.4163），但与逐步上升的疾病演变风险显着相关（总体 p = 0.0002）。此外，我们发现血细胞比容和血小板计数均与血栓形成或疾病演变的危险性没有显着相关性。我们发现持续升高的白细胞轨迹与血栓形成事件的风险无关（p = 0.4163），但与逐步上升的疾病演变风险显着相关（总体 p = 0.0002）。此外，我们发现血细胞比容和血小板计数均与血栓形成或疾病演变的危险性没有显着相关性。我们发现持续升高的白细胞轨迹与血栓形成事件的风险无关（p = 0.4163），但与逐步上升的疾病演变风险显着相关（总体 p = 0.0002）。此外，我们发现血细胞比容和血小板计数均与血栓形成或疾病演变的危险性没有显着相关性。