A simplified version of the Pulmonary Embolism Severity Index identified patients with acute pulmonary embolism who were at low risk of adverse events and might be suitable for outpatient care, investigators reported in Academic Emergency Medicine.
“Although guidelines, such as those from the American College of Chest Physicians, recommend outpatient treatment for selected PE patients at low risk of recurrence, existing evidence for the outpatient management of patients with PE is derived from small cohorts of patients from outside the United States,” said Dr. Gregory J. Fermann of the University of Cincinnati department of emergency medicine and his associates.
“The results of this analysis provide further support that risk stratification of PE patients may allow a cohort of low-risk patients to be treated in a clinical decision unit or by a closely monitored outpatient strategy. Such an approach might relieve some of the burden placed on the emergency department (Acad. Emerg. Med. 2015;22:299-307).”
The PESI has been shown to identify patients at increased risk of death and adverse outcome events after acute PE. The simplified PESI has 6 of the PESI’s 11 variables, but remains accurate in assessing PE severity, the researchers said. They carried out a post hoc analysis of simplified PESI scores and outcomes among 4,831 acute PE patients from the phase III Einstein PE study, in which rivaroxaban was found noninferior to an enoxaparin–vitamin K antagonist combination in terms of the risk of recurrent venous thromboembolism and clinically important bleeding events (N. Engl. J. Med. 2012;366:1287-97).
Roughly half (53.6%) of the patients had a score of 0, one-third (36.7%) had a score of 1, and 9.7% had a score of 2 or 3, the researchers reported. Higher simplified PESI scores were associated with increased risk of almost all adverse outcomes measured, including recurrent VTE, fatal PE, all-cause mortality, and major bleeding. Patients with scores of 0 or 1 had low rates of major adverse events during the first 30 days of treatment, regardless of which protocol they received.
However, the incidence of major bleeds up to 30 days was lower in the rivaroxaban group than in the standard treatment group, especially if patients’ simplified PESI scores were greater than 0. Scores of 2 or 3 were associated with greater risk of recurrent VTE, fatal PE, all-cause mortality, and major bleeding at all time points and in both treatment groups.
Bayer HealthCare Pharmaceuticals and Janssen Research & Development funded the study. Dr. Fermann reported an advisory relationship with Janssen and research funding from Cardiorentis, Trevena, Novartis, Siemens, and Pfizer. Two coauthors reported employment with Bayer, and two other coauthors reported financial and advisory relationships with several other pharmaceutical companies.