Incidence of and risk factors for venous thrombosis in hospitalized patients with hematologic malignancies: A single-center, prospective cohort study.

Objective: Incidence of venous thromboembolism (VTE) is higher than the expected in patients with hematologic malignancies and duration of hospitalization period increases the risk of thrombosis. The objective of this study was to investigate the incidence of and risk factors for venous thrombosis in hospitalized patients with hematologic malignancies.

Methods: We designed a prospective cohort study and enrolled patients with hematologic malignancies, who had been hospitalized between 2020 and 2021. Thromboprophylaxis was given to all patients, other than those under a high risk of hemorrhage.

Results: 94 patients were enrolled. The incidence of superficial vein thrombosis was 11.7% and the incidence of deep vein thrombosis (including pulmonary embolism and catheter thrombosis) was 7.4%. Patients, who developed thrombosis, had statistically significantly longer hospital stays (21 vs. 11.5 days, p=0.023) and a higher number of hospitalizations (1 vs. 3, p=0.015) compared to those, who did not develop thrombosis. Patients, who had 3 or more risk factors for thrombosis, were found to be under the highest risk. (p=0.017, OR=4.32; 95% CI: 1.3-14.35). Furthermore, patients with recurrent hospitalizations (p=0.024, OR=1.49; 95% CI: 1.05-2.11) and higher fibrinogen levels (p=0.028, OR=1; 95% CI: 1-1.006) were under an increased risk of thrombosis.

Conclusion: Venous thrombosis is frequently seen in hospitalized patients with hematologic malignancies. A universally accepted risk scoring system is required for detection of patients, under a high risk for thrombosis.