title: Leukocytosis is a risk factor for recurrent arterial thrombosis in young patients with polycythemia vera and essential thrombocythemia.
abstract: There is evidence that leukocytosis is associated with an increased risk of first thrombosis in patients with polycythemia vera (PV) and essential thrombocythemia (ET). Whether it is a risk factor for recurrent thrombosis too is currently unknown. In the frame of a multicenter retrospective cohort study, we recruited 253 patients with PV (n = 133) or ET (n = 120), who were selected on the basis of a first arterial (70%) or venous major thrombosis (27.6%) or both (2.4%), and who were not receiving cytoreduction at the time of thrombosis. The probability of recurrent thrombosis associated with the leukocyte count recorded at the time of the first thrombosis was estimated by a receiver operating characteristic analysis and a multivariable Cox proportional hazards regression model. Thrombosis recurred in 78 patients (30.7%); multivariable analysis showed an independent risk of arterial recurrence (hazard ratio [HR] 2.16, 95% CI 1.12-4.18) in patients with a leukocyte count that was >12.4 x 10(9)/L at the time of the first thrombotic episode. The prognostic role for leukocytosis was age-related, as it was only significant in patients that were aged <60 years (HR for arterial recurrence 3.35, 95% CI 1.22-9.19).
authors.affiliation: The Institute of Hematology, Catholic University, Rome, Italy. valerio.destefano@rm.unicatt.it
authors.forename: Valerio
authors.initials: V
authors.lastname: De Stefano
authors.forename: Tommaso
authors.initials: T
authors.lastname: Za
authors.forename: Elena
authors.initials: E
authors.lastname: Rossi
authors.forename: Alessandro M
authors.initials: AM
authors.lastname: Vannucchi
authors.forename: Marco
authors.initials: M
authors.lastname: Ruggeri
authors.forename: Elena
authors.initials: E
authors.lastname: Elli
authors.forename: Caterina
authors.initials: C
authors.lastname: Micò
authors.forename: Alessia
authors.initials: A
authors.lastname: Tieghi
authors.forename: Rossella R
authors.initials: RR
authors.lastname: Cacciola
authors.forename: Cristina
authors.initials: C
authors.lastname: Santoro
authors.forename: Giancarla
authors.initials: G
authors.lastname: Gerli
authors.forename: Paola
authors.initials: P
authors.lastname: Guglielmelli
authors.forename: Lisa
authors.initials: L
authors.lastname: Pieri
authors.forename: Francesca
authors.initials: F
authors.lastname: Scognamiglio
authors.forename: Francesco
authors.initials: F
authors.lastname: Rodeghiero
authors.forename: Enrico M
authors.initials: EM
authors.lastname: Pogliani
authors.forename: Guido
authors.initials: G
authors.lastname: Finazzi
authors.forename: Luigi
authors.initials: L
authors.lastname: Gugliotta
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Leone
authors.forename: Tiziano
authors.initials: T
authors.lastname: Barbui
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007958:Leukocyte Count; D007964:Leukocytosis / Q000097:blood / Q000150:complications / Q000453:epidemiology* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D011087:Polycythemia Vera / Q000097:blood / Q000150:complications / Q000453:epidemiology* / Q000628:therapy; D012189:Retrospective Studies; D012307:Risk Factors; D013920:Thrombocythemia, Essential / Q000097:blood / Q000150:complications / Q000453:epidemiology* / Q000628:therapy; D013927:Thrombosis / Q000097:blood / Q000453:epidemiology* / Q000209:etiology / Q000628:therapy