Treatment and Outcomes of Acute Pulmonary Embolism and Deep Venous Thrombosis: The CVRN VTE Study.

Background: Few studies describe both inpatient and outpatient treatment and outcomes of patients with acute venous thromboembolism in the United States.

Methods: A multi-institutional cohort of patients diagnosed with confirmed pulmonary embolism or deep venous thrombosis during the years 2004 through 2010 was established from 4 large, US-based integrated health care delivery systems. Computerized databases were accessed and medical records reviewed to collect information on patient demographics, clinical risk factors, initial antithrombotic treatment, and vital status. Multivariable Cox regression models were used to estimate the risk of death at 90 days.

Results: The cohort comprised 5497 adults with acute venous thromboembolism. Pulmonary embolism was predominantly managed in the hospital setting (95.0%), while 54.5% of patients with lower extremity thrombosis were treated as outpatients. Anticoagulant treatment differed according to thromboembolism type: 2688 patients (92.8%) with pulmonary embolism and 1625 patients (86.9%) with lower extremity thrombosis were discharged on anticoagulants, compared with 286 patients (80.1%) with upper extremity thrombosis and 69 (54.8%) patients with other thrombosis. While 4.5% of patients died during the index episode, 15.4% died within 90 days. Pulmonary embolism was associated with a higher 90-day death risk than lower extremity thrombosis (adjusted hazard ratio 1.23; 95% confidence interval, 1.04-1.47), as was not being discharged on anticoagulants (adjusted hazard ratio 5.56; 95% confidence interval, 4.76-6.67).

Conclusions: In this multicenter, community-based study of patients with acute venous thromboembolism, anticoagulant treatment and outcomes varied by thromboembolism type. Although case fatality during the acute episode was relatively low, 15.4% of people with thromboembolism died within 90 days of the index diagnosis.