What are the NEWS in pulmonary embolism risk stratification?
Authors: Grade Santos J , Cale R , Martinho M , Ferreira B , Cunha D , Briosa A , Goncalves De Sousa B , Leote J , Pestana Santos C , Cruz D , Araujo P , Santos J , Judas T , Ferreira F , Pereira H 
Published: October 2022

Abstract

Introduction
The patients with Pulmonary Thromboembolism (PE) stratified as intermediate-high risk with the European Society of Cardiology classification represent an heterogenous population, with the majority having a benign outcome however some evolving in clinical deterioration. Several risk scores have been developed to try and refine the population most at risk but they are deemed sub-optimal.

Purpose
Our aim was to assess the capacity of the National Early Warning Score (NEWS) in predicting a composite end-point of 30-days cardiovascular mortality, rescue thombolysis and/or haemodynamic instability, in a population of intermediate-high risk PE, as compared with other risk evaluation scores as the PESI and SHIeLD scores.

Methods
We performed a retrospective analysis between 2014 and 2019 of all patients admitted for intermediate-high risk PE, in a single expert centre. The patients who underwent fibrinolysis as per clinician discretion (without haemodynamically instability or clinical evidence of clinical deterioration) were excluded. Medical records were analysed for clinical data and outcomes. The predictive accuracy of all scores were assessed using the area under curve (AUC) of receiver operating characteristics (ROC) curve. The association between NEWS and composite end-point at 30-days was analyzed using a Cox regression model.

Results
Of the 1132 patients assessed and admitted with PE, 116 patients fulfilled all inclusion criteria and none of the exclusion criteria and were analysed. The mean age was 69±16 years at time of diagnosis with a female preponderance (62.9%). Most patients were treated with anticoagulation (97.4%), 68% with low molecular weight heparin and the remaining with unfractionated heparin. The average NEWS score was 7±3, the average PESI score was 110±34 and the average SHIeLD score was 14±13. A primary composite end-point occurred in 18 patients (15.5%). The NEWS score showed the greatest predictive power for the occurrence of an event (OR 1.35; 95% CI 1.11–1.64, p=0.003) compared with the SHIeLD score (OR 1.0; 95% CI 1.00–1.07, p=0.035) and the PESI score (OR 1.02; 95% CI 1.00–1.03, p=0.03); it also showed a greatest discriminative capacity with the ROC curve analysis (Figure 1A) demonstrating an AUC of 0.70, vs 0.65 and 0.62 respectively. The survival analysis demonstrated a Hazard Ratio of 1.29 (95% CI 1.10–1.52; p=0.002) signifying a 29% increased risk of an event per each NEWS class increase, with the Kaplan Meier curves widening significantly in the different terciles of the score (Figure 1B).

Conclusions
In PE patients with intermediate-high risk the NEWS score demonstrated a greater predictive power and discriminative capacity than other commonly used risk scores. The NEWS score may help to identify patients in this risk category who might benefit from a reperfusion strategy, but larger studies are needed to confirm this hypothesis.

Funding Acknowledgement
Type of funding sources: None.