OBJECTIVESTo explore the frequency, clinical features and risk factors of venous thromboembolism (VTE) in hospitalized patients.

METHODSThe frequency, demographic features, and acquired and inherited factors of in-patient cases of VTE in Peking union medical college hospital from 1994 to 2004 were analyzed retrospectively.

RESULTSSix hundred and seventy-two patients were enrolled. Among them, male to female ratio was 1.2 and the median age was 53 (14 - 92). Five hundred and eighty (86.3%) patients were at their first diagnosis with the peak ages between 40 and 50 for men and 50 and 60 for women. More common acquired risk factors were antiphospholipid antibody syndrome (APS) (32.0%), trauma / surgery (31.1%) and malignancies (17.1%). 35.7% of the patients had multiple acquired risk factors. Before the initiation of anticoagulation therapy, the activities of protein C (PC), protein S (PS) and antithrombin (AT) were measured in 94 patients. The deficiency of these three natural anticoagulants was 44.7%. Among the anticoagulant deficiencies, PC deficiency was the commonest one (13.8%). Combined deficiency of PC and AT accounted for 10.6%. 31.6% of the 94 patients had inherited plus acquired risk factors.

CONCLUSIONSAge for the first event of VTE in the men was about 10 years ahead of that in the women. The major acquired risk factors were APS, trauma/surgery and malignancies, and inherited risk factors were PC deficiency and PC + AT combined deficiencies. It seems that the coexistence of multiple risk factors plays an important role in triggering VTE.