title: [Clinical characteristics and risk factors for major thrombosis in 604 Chinese patients with low-risk essential thrombocythemia].
abstract: OBJECTIVE
  To analyze clinical and molecular characteristics of low-risk essential thrombocythemia (ET) in a large cohort of Chinese patients and to explore risk factors for major thrombosis and treatment strategies.
  
  
  METHODS
  Medical records of patients with an initial diagnosis of ET from March 1982 to May 2012 in our hospital were retrospectively analyzed.
  
  
  RESULTS
  A total of 604 low-risk ET patients were enrolled with a median follow-up of 49 months (range:0-338). 43(7.1%) patients experienced major thrombotic events. Cox proportional hazards regression revealed JAK2 V617F mutation (HR=2.279; P=0.035) and cardiovascular risk factors (CVF) (HR=2.541; P=0.006) to be risk factors for total thrombotic events, while only CVF (HR=2.633; P=0.008) was risk factor for arterial thrombosis. None of the evaluated factors was related to venous thrombosis. Patients with both JAK2 V617F mutation and CVF had a worse thrombosis- free survival than those with only one risk factor (P<0.05). In patients with JAK2 V617F or CVF alone, antiplatelet treatment (P=0.016) significantly decreased the risk of thrombosis, while those with both JAK2 V617F and CVF could benefit from cytoreductive agents (P=0.018).
  
  
  CONCLUSIONS
  Chinese low-risk ET patients have a lower risk of thrombosis than Caucasian low-risk ET patients. JAK2 V617F mutation and CVF are the most significant risk factors for thrombosis. Existence of both risk factors further increases the thrombotic risk. Treatment strategies on low-risk ET patients should be made based on presence or absence of risk factors.
authors.affiliation: State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, CAMS & PUMC, Tianjin 300020, China.
authors.forename: Rongfeng
authors.initials: R
authors.lastname: Fu
authors.affiliation: State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, CAMS & PUMC, Tianjin 300020, China.
authors.forename: Min
authors.initials: M
authors.lastname: Xuan
authors.affiliation: State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, CAMS & PUMC, Tianjin 300020, China.
authors.forename: Liyan
authors.initials: L
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, CAMS & PUMC, Tianjin 300020, China.
authors.forename: Huiyuan
authors.initials: H
authors.lastname: Li
authors.affiliation: State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, CAMS & PUMC, Tianjin 300020, China.
authors.forename: Tiantian
authors.initials: T
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, CAMS & PUMC, Tianjin 300020, China.
authors.forename: Donglei
authors.initials: D
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, CAMS & PUMC, Tianjin 300020, China.
authors.forename: Xian
authors.initials: X
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, CAMS & PUMC, Tianjin 300020, China.
authors.forename: Cuicui
authors.initials: C
authors.lastname: Lyu
authors.affiliation: State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, CAMS & PUMC, Tianjin 300020, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Xue
authors.affiliation: State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, CAMS & PUMC, Tianjin 300020, China.
authors.forename: Xiaofan
authors.initials: X
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, CAMS & PUMC, Tianjin 300020, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, CAMS & PUMC, Tianjin 300020, China.
authors.forename: Renchi
authors.initials: R
authors.lastname: Yang
mesh_terms: D044466:Asian People; D006801:Humans; D053614:Janus Kinase 2; D009154:Mutation; D012189:Retrospective Studies; D012307:Risk Factors; D013921:Thrombocytopenia / Q000150:complications*; D013927:Thrombosis / Q000235:genetics*
chemical_list: D053614:Janus Kinase 2