This document summarizes a study examining the length of stay and economic implications of treating pulmonary embolism with rivaroxaban versus low molecular weight heparin-vitamin K antagonist (LMWH-VKA) in an emergency room setting. The study found that among patients in North America from the EINSTEIN PE trial, the median length of stay was 1 day shorter for those treated with rivaroxaban (3 days) compared to LMWH-VKA (4 days). This 1 day reduction in length of stay was associated with an estimated $2040 savings per patient for the rivaroxaban cohort based on average hospital costs. The study concluded that rivaroxaban was associated with a consistent

1. Treatment of Pulmonary Embolism with
Rivaroxaban and LMWH-VKA in the
Emergency Room Setting: Length of
Stay and Economic Implications
Brahim K. Bookhart, Lloyd Haskell, Luke
Bamber, Maria Wang, Jeff Schein, Samir H.
Mody
1

2. EINSTEIN PE study
Randomized, open-label, event-driven, non-inferiority study
Predefined treatment period of 3, 6, or 12 months
Day 21
Rivaroxaban
Confirmed
PE with or
without
symptomatic
DVT2
N=4833
Rivaroxaban
15 mg bid
20 mg od
N=4833
R
Enoxaparin bid for at least 5 days +
VKA, INR 2.0–3.0
30-day post-study
treatment period
Day 1

Primary efficacy outcome: first recurrent VTE

Principal safety outcome: first major or non--major clinically relevant
bleeding
1. The EINSTEIN Investigators. N Engl J Med 2010;363:2499–510;
2. The EINSTEIN–PE Investigators. N Engl J Med 2012;366:1287–97

3. Methods
 Examined the North American EINSTEIN PE cohort - United
States and Canada
 Previous analysis on entire international EINSTEIN PE study
presented at American Society of Hematology: found median
length of stay difference of 1 day: 6.0 (4.0–9.0) vs. 7.0 (5.0–10.0)
 LOS medians and exponentiated least squares mean of logtransformed LOS; nominal P-value was obtained from a Wilcoxon
rank-sum test (van Elteren test)
 Costs for hospital days were taken from the Healthcare Cost and
Utilization Project (HCUP)
Family of healthcare databases developed through a federal–state–
industry partnership and sponsored by the Agency for Healthcare
Research and Quality
The average cost per day for PE treatment was $2040
*American Society of Hematology (ASH) 54th Annual Meeting and Exposition, Atlanta, GA, USA; December 8–11, 2012
3

4. Results
Patient
population
Complete data on
hospitalization
available, n
Hospitalized, n
(%)
Hospitalized with
complete data on
length of stay, n
Median length of
stay, days
(interquartile
range)
Exponentiated
LS-mean of log
transformed
length of stay
Rivaroxaban
(n=244)
Enoxaparin/
VKA
(n=242)
244
241
163 (66.8)
160 (66.6)
162
159
3 (3.0–5.0)
4.2
LOS
Reduction
Pvalue
4 (3.0–6.0)
1.0
0.0002
5.2
1.0
0.0013
 Consistent one day reduction in hospitalization associated with
$2040 cost savings for rivaroxaban cohort
4