Application of Loading Dose Warfarin in Postpartum Women with Pulmonary Embolism - a Prospective, Randomized,...

Warfarin is usually used in a fixed loading dose regimen, which may increase the risk of bleeding or prolong the time to reach standard dose. The aim of the study is to compare the efficacy and safety of loading dose versus maintenance dose of warfarin therapy in postpartum women with pulmonary embolism (PE) under the guidance of clinical pharmacogenetic information.

A total of 64 postpartum women with PE were recruited from September 2022 to August 2023. Participants were randomly divided 1:1 into two groups using a random-number table patients in the experimental group received a regimen combining the initial 1 to 3 days loading dose with the International Warfarin Pharmacogenetics Consortium (IWPC) model. Patients in the control group only received a regimen guided by the IWPC model for the initial 1 to 3 days. Starting from day 4, the warfarin dose was adjusted according to the international normalized ratio (INR). The primary outcome was first time to therapeutic INR (2.0-3.0).

The study found that the median time to first reach the therapeutic INR was 5.5 days in the experimental group compared to 7 days in the control group (p=0.002). The median time within therapeutic range (TTR) was 97.24% in the experimental group compared to 95.50% in the control group (p=0.001). The difference in adverse events showed no statistical significance between the two groups (P > 0.05).

The study could provide ideas for the precise treatment of warfarin in postpartum women with PE. The integration of warfarin loading doses guided by pharmacogenetics into clinical practice can enhance decision-making, optimize patient outcomes, and reduce adverse events.