Pulmonary emboli and deep vein thromboses: Are they always part of the same disease spectrum?

Background: Pulmonary embolis (PEs) are thought to emanate from deep vein thromboses (DVTs). Government agencies now use thromboembolic events as a quality metric for reimbursement for care. Recent data suggest that PEs and DVTs may represent different pathologic processes. We sought to identify separate risk factors for PEs and DVTs to test whether they are the same disease process. Methods: A retrospective review of the National Trauma Data Bank between 2007 and 2010 was performed. Demographics, complications, comorbidities, and injury data were reviewed for risk factors for patients diagnosed with a PE or DVT. Results: After exclusion criteria were met 521,969 patient entries were analyzed. Of these patients, 4,154 and 1,460 had a DVT or PE, respectively,while 8% (433) of patients had both. PEs and DVTs, had 18 overlapping risk factors, 26 independent risk factors (5 for PEs; 21 for DVTs), and one divergent risk factor. Conclusion: Despite PEs and DVTs having overlapping risk factors, there are significant independent and divergent risk factors for the two diseases, suggesting that they are not always part of the same process. The constellation of risk factors for each disease may help to predict which one patient is predisposed to and draws into question the concept of using them as a quality metric as whether therapeutic anticoagulation is indicated in trauma patients.