Modified IMPROVE VTE Risk Score and Elevated D-Dimer Identify a High Venous Thromboembolism Risk in Acutely Ill Medical Population for Extended Thromboprophylaxis.

Gary E Raskob,Alex C Spyropoulos,Concetta Lipardi,Elliot S Barnathan,Jianfeng Xu,Theodore E Spiro,Yoriko De Sanctis,Colleen Peluso

doi:10.1055/s-0040-1705137

Abstract

An individualized approach to identify acutely ill medical patients at increased risk of venous thromboembolism (VTE) and a low risk of bleeding to optimize the benefit and risk of extended thromboprophylaxis (ET) is needed. The International Medical Prevention Registry on Venous Thromboembolism (IMPROVE) VTE risk score has undergone extensive external validation in medically ill patients for in-hospital use and a modified model was used in the MARINER trial of ET also incorporating an elevated D-dimer. The MAGELLAN study demonstrated efficacy with rivaroxaban but had excess bleeding. This retrospective analysis investigated whether the modified IMPROVE VTE model with an elevated D-dimer could identify a high VTE risk subgroup of patients for ET from a subpopulation of the MAGELLAN study, which was previously identified as having a lower risk of bleeding. We incorporated the modified IMPROVE VTE score using a cutoff score of 4 or more or 2 and 3 with an elevated D-dimer (>2 times the upper limit of normal) to the MAGELLAN subpopulation. In total, 56% of the patients met the high-risk criteria. In the placebo group, the total VTE event rate at Day 35 was 7.94% in the high-risk group and 2.83% for patients in the lower-risk group. A reduction in VTE was observed with rivaroxaban in the high-risk group (relative risk [RR]: 0.68, 95% confidence interval [CI]: 0.51–0.91, p = 0.008) and in the lower-risk group (RR: 0.69, 95% CI: 0.40 -1.20, p = 0.187). The modified IMPROVE VTE score with an elevated D-dimer identified a nearly threefold higher VTE risk subpopulation of patients where a significant benefit exists for ET using rivaroxaban.

Highlights

The identification of hospitalized medically ill patients at high risk of venous thromboembolism (VTE) with a low risk of bleeding that would benefit from extended thromboprophylaxis (ET) in the post-hospital discharge period remains an important unmet clinical need.[1]
This study revealed that a modified International Medical Prevention Registry on Venous Thromboembolism (IMPROVE) VTE risk score with a score of 4 or more or a score of 2 or 3 plus an elevated
For hospitalized medically ill patients, the modified IMPROVE VTE risk score incorporating an elevated D-dimer as a biomarker identified a nearly threefold higher VTE risk patient population for whom a significant benefit exists for ET of up to 35 days with rivaroxaban

Summary

Introduction

The identification of hospitalized medically ill patients at high risk of venous thromboembolism (VTE) with a low risk of bleeding that would benefit from extended thromboprophylaxis (ET) in the post-hospital discharge period remains an important unmet clinical need.[1]. Antithrombotic guidelines have suggested or recommended against routine use of ET in medically ill patients but have adopted an individualized approach in assessing a hospitalized medical patient’s risk of VTE and bleeding.[5,6] The International Medical Prevention Registry on Venous Thromboembolism (IMPROVE) tool is a weighted VTE risk score that has been derived in medically ill patients and has undergone extensive external validation.[7,8,9,10] A modified version of the IMPROVE VTE risk score that incorporated an elevated D-dimer was used as part of the inclusion criteria for the MARINER trial of ET with rivaroxaban.[11]. The IMPROVE VTE risk score has been highlighted as a key VTE risk assessment model for clinician decision-making in assessing VTE risk in hospitalized medical patients.[6]

Methods

Results

Discussion

Conclusion