Thrombotic complications of polycythemia vera

Polycythemia vera (PV) is an uncommon clonal disorder of stem cells. The literature regarding the thrombotic complications of this disorder in the developing countries is scarce. The present study was undertaken retrospectively to look at the association of thrombotic complications of PV with various patient characteristics.

All the patients diagnosed to have PV from January 1986 to December 2005 according to Polycythemia Vera Study Group criteria were included. Their clinical characteristics, laboratory parameters, clinical complications such as thrombosis and myelofibrosis, treatment modalities, malignancies and deaths, if any were noted. The various characteristics of patients who had developed thrombosis were compared statistically with those of patients without thrombosis.

Out of the 9550 patients seen during this period, 32 patients fulfilled the inclusion criteria. The median age at the time of diagnosis was 56.5 years. Eight patients developed thrombotic complications; out of which four had arterial and four had venous thrombosis. There was no statistically significant difference in the mean hemoglobin, white cell count (WBC), platelet count and RBC mass in patients with thrombosis as compared to patients without thrombosis. These parameters were also not statistically significant when patients with arterial thrombosis were compared with patients with venous thrombosis.

PV is an uncommon disorder when compared with other hematological disorders in northern India. There was no relationship between the development of thrombotic complications and hemoglobin, RBC mass or platelet count. Twenty patients received hydroxyurea with a median follow-up of 57 months, none developed acute leukemia.