Treatment of venous thromboembolism: adherence to guidelines and impact of physician knowledge, attitudes, and beliefs

Abstract

Objectives: To assess the treatment of venous thromboembolism (VTE) in hospitalized patients enrolled in a national, multicenter database.

Methods: This was a retrospective, cohort study that randomly selected VTE patients from 38 academic/teaching, community, and Veterans Administration (VA) hospitals. The study included a physician survey component. The patients selected were those treated between January 2002 and June 2003 who had an ICD-9-CM code for pulmonary embolus (PE), deep vein thrombosis (DVT), or pregnancy-related PE or DVT.

Results: The study included 939 patients: 52.7% with DVT, 28.4% with PE, and 18.8% with PE and DVT. Mean age was 59.5 years. Risk factors included obesity (body mass index > 30) in 30.1%, history of VTE in 28.0%, malignancy in 27.4%, surgery in 21.1%, and immobility in 18.5%. Only 56.1% of patients were treated with low-molecular-weight heparin (LMWH). Bridging from LMWH or unfractionated heparin (UFH) to warfarin was completed during hospitalization in 486 (68.6%), but only 246 (50.6%) had an international normalized ratio (INR) > or = 2 for 48 hours before discontinuation of the injectable anticoagulant. Length of stay in patients discharged on bridge therapy was 4.0 +/- 3.7 days vs 8.1 +/- 5.8 days for patients discharged on warfarin therapy (P < .001). Ninety-two (10.1%) patients were discharged with neither oral nor injectable anticoagulation and had a mean duration of treatment of only 10.6 +/- 16.2 days. Of 245 physicians surveyed from participating hospitals, 84% and 53%, respectively, indicated that LMWH was their preferred agent for treatment of DVT and treatment of PE. With regard to warfarin, 30% did not believe it was necessary to have a therapeutic INR for > or = 2 days before discontinuing LMWH or UFH, and 27% responded that it was necessary to keep DVT patients in the hospital until they were therapeutic.

Conclusions: In this cross-section of United States hospitals, lower than anticipated use of LMWH, insufficient bridging from UFH or LMWH to warfarin, and continuation of anticoagulation after hospitalization were all problems discovered with the treatment of VTE. Physician knowledge, attitudes, and beliefs are partially responsible for the gap between actual practice and international guidelines. These results suggest that hospitals should evaluate their adherence to international VTE treatment guidelines and develop strategies to optimize antithrombotic therapy.