The Risk Factors for Pulmonary Embolism in Patients with Lower Extremity Deep Vein Thrombosis

ABSTRACT

PURPOSE: Pulmonary embolism (PE) represents the most important and fatal complication of deep vein thrombosis (DVT), of which a dislodged thrombus is most commonly derived from the deep venous system of the lower extremity. The aim of this study is to define the incidence and risk factors of PE in DVT patients. METHOD: We retrospectively reviewed 248 patients with DVT in a lower extremity at Uijeongbu St. Mary's Hospital between January 2000 and August 2008 and they had received additional examinations for making the diagnosis of PE regardless of its symptoms. RESULT: There were 117 men and 131 women, and their mean age was 59 years old (range 13~91) at the time of diagnosis. There were 190 DVT-only patients and 58 patients with PE (the incidence rate of PE in the DVT patients 23.8%). The gender ratio of the DVT only group was 11.3 (males 83, female 107) and the gender ratio of the DVT with PE group was 10.7 (males 34, females 24) (P<0.05). The risk factors of PE in the DVT patients were hypercoagulability (34%), cancer (23%), immobilization (17%), trauma/operation (10%), obesity (10%) and a past DVT history (7%). The idiopathic DVT patients had a relatively high cancer diagnosis rate (18.5%) and the majority of the newly detected cancer were from the chest or abdominal cavity. CONCLUSION: The incidence of DVT and PE is increasing and 23.8% of the DVT patients showed PE on their chest CT scan. The most significant risk factor for PE in the DVT patients was the male gender, yet an evaluation for cancer should be carefully done for idiopathic DVT patients because of their high rate of having cancer diagnosed.