Icahn School of Medicine at Mount Sinai, New York, NY.
Hematology Section, Department of Medicine, Yale School of Medicine, New Haven, CT.
Blood. 2020 May 7;135(19):1696-1703. doi: 10.1182/blood.2019003347.
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 use 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 laboratory data at ∼3-month intervals (or as available) for all patients for duration of follow-up, we used group-based trajectory modeling to identify latent clusters of patients who follow distinct trajectories with regard to their leukocyte, hematocrit, and platelet counts over time. We then tested the association between trajectory membership and hazard of 2 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 the hazard of a thrombotic event (P = .4163), but were significantly associated with increased hazard of disease evolution in an ascending stepwise manner (overall P = .0002). In addition, we found that neither hematocrit nor platelet count was significantly associated with the hazard of thrombosis or disease evolution.
关于持续性白细胞增多与真性红细胞增多症（PV）血栓形成风险和疾病进展之间的关联，仍存在一些悬而未决的问题，因为该主题的许多已发表文献并没有使用重复测量数据或时间依赖性模型来恰当地回答这些问题。为了解决这一知识空白，我们分析了美国 10 家学术机构的 520 例 PV 患者的回顾性数据库。对所有患者在随访期间大约每 3 个月（或根据可用情况）的血液学实验室数据进行分析，我们使用基于群组的轨迹建模来识别患者的潜在群组，这些患者在白细胞、红细胞压积和血小板计数随时间的变化方面具有不同的轨迹。然后，我们检验了轨迹成员与 2 个主要结局（血栓形成和疾病向骨髓纤维化、骨髓增生异常综合征或急性髓系白血病的进展）之间的关联。在控制相关协变量的情况下，我们发现持续性白细胞增多轨迹与血栓形成事件的风险无关（P=0.4163），但与疾病进展风险呈递增阶梯式显著相关（整体 P=0.0002）。此外，我们发现红细胞压积或血小板计数均与血栓形成或疾病进展的风险无显著关联。
