Evaluation of Venous Thromboembolism Recurrence Scores in an Unprovoked Pulmonary Embolism Population: a post-hoc analysis of the PADIS-PE trial

International audience ; INTRODUCTION We aimed to validate the HERDOO2 DASH and Updated Vienna recurrent venous thromboembolism prediction models in a population composed entirely of first unprovoked pulmonary embolism and analyzed the impact of the addition of pulmonary vascular obstruction index (PVOI) on score accuracy.METHODS Analyses were based on the double-blind randomized PADIS-PE trial including 371 unprovoked pulmonary embolism patients initially treated during 6 months successively randomized to receive an additional 18-months of warfarin or placebo and subsequently followed-up for two years.RESULTS The HERDOO2 DASH and Updated Vienna scores displayed c-statistics of 0.61 (95%CI 0.54-0.68) 0.60 (95%CI 0.53-0.66) and 0.58 (95%CI 0.51-0.66) respectively. Only the HERDOO2 score identified low recurrence risk patients (<3%/year) after stopping anticoagulation. When added to either of the prediction models PVOI measured at pulmonary embolism diagnosis and/or after 6 months of anticoagulation improved scores' c-statistics between +0.06 and +0.11 points and consistently led to identifying at least 50% of patients who experienced recurrence but in whom the scores would have indicated against extended anticoagulation.CONCLUSIONS In patients with a first unprovoked pulmonary embolism the HERDOO2 score is able to identify patients with a low recurrence risk after treatment discontinuation. Addition of PVOI improves accuracy of all scores.CLINICAL TRIALS REGISTRATION URL http//www.controlled-trials.com. Unique identifier NCT00740883.