Anticoagulant bridge therapy may be harmful for patients with a low to moderate risk of venous thromboembolism (VTE), according to research published in JAMA Internal Medicine.
The study included more than 1000 patients with VTE who had to stop receiving warfarin prior to a procedure.
Investigators compared outcomes in patients who received bridge therapy—a short-acting anticoagulant during the periprocedural period—and patients who did not.
Nathan Clark, PharmD, of Kaiser Permanente Colorado in Aurora, and his colleagues conducted this research.
They examined the electronic medical records of 1178 patients with VTE who underwent 1812 invasive diagnostic or surgical procedures between January 2006 and March 2012 that required the interruption of warfarin.
The investigators divided patients into 3 groups based on their annual risk of VTE recurrence without anticoagulant therapy. Seventy-nine percent of patients were categorized as low-risk, 17.9% as moderate-risk, and 3.1% as high-risk.
The team then divided patients according to the use of bridge therapy. Of the 1812 procedures, 555 included bridge therapy, and 1257 did not.
Patients in the bridged group had a significantly higher incidence of clinically relevant bleeding at 30 days than patients in the non-bridged group—2.7% and 0.2%, respectively (P=0.01).
When the investigators assessed patients according to VTE risk, they found the increased incidence of bleeding in the bridged group was significant among low-risk patients (2.0% vs 0.1%, P<0.001) and moderate-risk patients (4.6% vs 0%, P=0.004) but not high-risk patients (5.6% vs 4.8%, P=0.90).
On the other hand, there was no significant difference in VTE recurrence between the bridged and non-bridged groups—for all risk categories (0 vs 3 cases, P=0.56), low-risk patients (0 vs 2, P=0.37), moderate-risk patients (0 vs 1, P=0.48), or high-risk patients (0 vs 0, P>0.99)
The investigators said further research is needed to identify patient and procedure-related characteristics associated with the highest risk for perioperative VTE recurrence where targeted bridge therapy may be beneficial.
