Reduced Emergency Room Utilization for Initiation of Anticoagulation with Rivaroxaban Treatment of Cancer-Associated Thrombosis
Authors: Soff Aaron P , Dong Judy , Mantha Simon , Soff Gerald A. 
Published: October 2019

Abstract

Venous thromboembolism (VTE) is a leading cause of mortality and morbidity in cancer patients, and management represents a major cost to the healthcare system. We have previously presented in a cohort of 200 patients with cancer-associated thrombosis, rivaroxaban provides an alternative to low molecular weight heparin (LMWH), with 4.4% recurrent VTE and 2.2% major bleeding at 6 months (Mantha et al, ASH Abstract, 2015). Other recent publications have provided similar support for use of rivaroxaban in treatment of cancer-associated thrombosis (Bott-Kitslaar et al, Am J Med. 2016, Prins et al, Lancet Haem, 2014). In our early experience with rivaroxaban, fewer patients were sent to the Emergency Room (ER) for initiation of rivaroxaban than LMWH. We now characterize the site and cost of initiation of anticoagulation for the full 200 rivaroxaban patient cohort and a similar cohort of patients treated with LMWH demonstrating significant changes in practice and cost savings.
In an IRB approved initiative we track all patients with cancer-associated thrombosis at MSKCC. We characterized the site of initiation of anticoagulation of the first 200 cancer patients with a pulmonary embolism (PE) or lower extremity deep vein thrombosis DVT since January 2014, treated with rivaroxaban. A similar cohort from June through December 2013 was treated with enoxaparin. We excluded patients whose VTE developed as an inpatient. Anticoagulation starts were classified as an emergency room (ER) visit or a second return outpatient visit on the same day for patient education and insurance authorization, a single outpatient visit, or telephone communication. Respective billing codes were then used as part of an economic evaluation to estimate the cost of the additional healthcare resources utilized, and therefore the costs saved by reduction in ER visits or second medical office visits.
In the first 6 months of rivaroxaban availability, there was no decrease in ER utilization, compared with LMWH use. After 6 months of rivaroxaban availability, there was a significant decrease in ER visits for VTE management (p=0.008), which resulted in a decrease from baseline of 71% to 34% after one year (p=0.0001). Also of note, after one year of rivaroxaban availability, 18% of newly diagnosed VTE were managed by a simple telephone call to the patient or family member, typically after a recent outpatient visit. Only 2 patients who were started on rivaroxaban had required an additional outpatient visit to our Hematology clinic for evaluation.
Based on 2016 Medicare billing codes, we calculated the cost for the additional resources utilized, beyond a single outpatient visit. During the first 6 months of rivaroxaban use, the cost of additional resources per 100 outpatient VTE patients ($47,067) was not significantly different than during the LMWH era ($43,144). However, as practice patterns evolved, ER utilization declined and more patients were managed without additional healthcare resources, resulting in an approximately 50% reduction in costs, for a savings of approximately $20,000 per 100 anticoagulation initiations.
Management of cancer-associated thrombosis with LMWH is painful to the patient and expensive to the healthcare system. Patient quality of life is improved by treatment with rivaroxaban versus LMWH, with no evidence of loss of safety or efficacy. In this analysis, we expand on our prior observation that demonstrated a marked reduction in ER visits or hematology consults for the purpose of anticoagulation initiation and also show a substantial cost savings, of approximately $20,000 per 100 VTE patients. These changes in practice developed over an 18-month period, presumably reflecting a learning curve as healthcare providers became more familiar and comfortable with rivaroxaban. Of course, some patients with a new cancer-associated thrombosis should be sent to an ER for evaluation, based on their hemodynamic state or co-morbidities. However, our findings suggest that a majority of patients with cancer-associated thrombosis do not require ER visits, improving patient quality of life and sparing healthcare resources.

Disclosures
Soff: Janssen Pharmaceuticals: Other: Summer Student Internship. Mantha:Janssen Scientific Affairs, LLC: Research Funding. Soff:Janssen Scientific Affairs, LLC: Consultancy, Research Funding.