Clinical and Economic Outcomes in Low-risk Pulmonary Embolism Patients Treated with Rivaroxaban versus Standard of Care

BACKGROUND: Rivaroxaban, a fixed-dose oral direct factor Xa inhibitor, does not require continuous monitoring and thus reduces the hospital stay and economic burden in low-risk pulmonary embolism (LRPE) patients. STUDY QUESTION: What is the effectiveness of rivaroxaban versus the standard of care (SOC; low-molecular-weight heparin, unfractionated heparin, warfarin) among LRPE patients in the Veterans Health Administration? STUDY DESIGN: Adult patients with continuous health plan enrollment for ≥12 months pre- and 3 months post-inpatient PE diagnosis (index date=discharge date) between October 1, 2011- June 30, 2015 and an anticoagulant claim during the index hospitalization were included. MEASURES AND OUTCOMES: Patients scoring 0 points on the simplified Pulmonary Embolism Stratification Index were considered low-risk and were stratified into SOC and rivaroxaban cohorts. Propensity score matching (PSM) was used to compare hospital-acquired complications (HACs), PE-related outcomes (recurrent venous thromboembolism, major bleeding, and death), and healthcare utilization and costs between the rivaroxaban and SOC cohorts. RESULTS: Among 6746 PE patients, 1918 were low-risk; of these, 73 were prescribed rivaroxaban, 1546 were prescribed SOC, and 299 were prescribed other anticoagulants during the index hospitalization. After 1:3 PSM, 64 rivaroxaban and 192 SOC patients were included. During the index hospitalization, rivaroxaban users (versus SOC) had similar inpatient length of stay (LOS; 7.0 vs 6.7 days, standardized difference [STD]=1.8) but fewer HACs (4.7% vs 10.4%; STD: 21.7). In the 90-day post-discharge period, PE-related outcome rates were similar between the cohorts (all p>0.05). However, rivaroxaban users had fewer outpatient (15.9 vs 20.4; p=0.0002) visits per patient as well as lower inpatient ($765 vs $2,655; p<0.0001), pharmacy ($711 vs $1,086; p=0.0033), and total costs ($6,270 vs $9,671; p=0.0027). CONCLUSIONS: LRPE patients prescribed rivaroxaban had similar index LOS and PE-related outcomes, but fewer HACs, and lower total costs than those prescribed SOC.