Reduced Emergency Room Utilization for Initiation of Anticoagulation with Rivaroxaban Versus Low Molecular Weight Heparin for Treatment of Cancer-Associated Thrombosis

Background: Venous thromboembolism (VTE) is a leading cause of mortality and morbidity in cancer patients. The current standard of care is to treat cancer-associated VTE with Low Molecular Weight Heparin (LMWH), which is more effective than vitamin K antagonists, such as warfarin. However, LMWH injections are painful, expensive, and a burden in healthcare resource utilization. Further, many of these patients are referred to an emergency room for education on self-injection techniques, an added health care cost. The Hematology/Anticoagulation Management Service at Memorial Sloan Kettering Cancer Center is developing rivaroxaban as a safe and effective alternative to LMWH for cancer-associated VTE. In this report, we demonstrate a significant reduction in the referral of patients to the MSKCC Urgent Care Center (UCC), our in-house emergency room, to initiate anticoagulation, resulting in a significant reduction in resource utilization. Methods: As a Quality Assessment Initiative, we track all patients with cancer-associated VTE at MSKCC receiving rivaroxaban since January 2014, and have a similar database of cancer-associated VTE from June through December 2013, treated with enoxaparin. For this utilization of resources study we evaluated where anticoagulation was initiated for treatment of a new pulmonary embolism or lower extremity deep vein thrombosis, specifying either a single outpatient visit, two outpatient visits on the same day, a telephone call, or a visit to the UCC. When patients had a second outpatient visit on the same day as diagnosis of the VTE, the second visit was for patient education on injection technique and insurance authorization. The site of anticoagulation initiation was by the judgment and discretion of the physician managing the patient's cancer. Patients who developed a VTE during a hospital stay or were managed at an outside emergency room were not included in this analysis, as our program has no influence in those settings. Statistical analysis was with the Chi-square test. Comparison of safety and efficacy of rivaroxaban and LMWH is the subject of a separate study. Results: As anticipated, changing from a parenteral anticoagulant to rivaroxaban (an oral agent) resulted in significant changes in practice (Table). Significantly fewer rivaroxaban patients required visits to the UCC than with enoxaparin (p=0.009). Fewer patients required a second outpatient, as well. When viewed in the aggregate of UCC or second outpatient visit, 82% of patients treated with enoxaparin required additional medical resources for initiation of anticoagulation, beyond a single outpatient visit, which decreased to 59% with rivaroxaban (p<0.001). Of note, 11% of rivaroxaban patients were initiated with a phone call only, typically after a recent medical visit and outpatient imaging. The reduction in UCC utilization was confined to weekday hours when the outpatient clinics are open. In all cases with enoxaparin and rivaroxaban, initiation of anticoagulation was in the UCC on weekends and between the hours of 6 PM and 8 AM on weekdays. Discussion: In addition to the burden of morbidity and mortality, management of cancer-associated VTE with LMWH is painful to the patient and expensive to the healthcare system. In our QAI we have been developing rivaroxaban as an oral alternative. Safety and efficacy are being analyzed separately. In addition to the markedly lower cost of rivaroxaban compared with enoxaparin, and patient quality of life preference, we also demonstrate a significant reduction in the healthcare resources associated with initiation of anticoagulation. Cancer patients tend to be higher risk and more complex than general medical patients and it remains appropriate for some to be evaluated in an emergency room for diagnosis and management. Despite this, we observed a reduction in emergency room visits for patients in this setting. One limitation to our findings is that our study was within a single institution, with a devoted Hematology/Anticoagulation Management Service. It would be appropriate to perform a similar analysis in other institutions, including non-cancer patients, to confirm these findings. Table 1. Sites of Initiation of Anticoagulation Enoxaparin Rivaroxaban UCC/Emergency Room (p=0.009) 127 (71%) 101 (57%) Two Outpatient Visits On The Same Day 20 (11%) 4 (2%) Outpatient, Single Visit 32 (18%) 53 (30%) Telephone 0 19 (11%) Total 179 177 Disclosures No relevant conflicts of interest to declare.

The Ottawa Hospital Regional Warfarin Anticoagulation Management Service. Efficacy and a Patient Satisfaction Survey

Background: 5% of the population over 65 is on oral anticoagulant therapy. The indications for anticoagulation therapy are wide, not limited to but including treatment of arterial and venous thrombosis, and primary stroke prophylaxis is patients with atrial fibrillation and mechanical cardiac valves. While new oral anticoagulants not requiring monitoring are being more widely prescribed, vitamin K antagonists (VKA) are still being used for many patients in whom the novel agents are contra-indicated (renal failure), not available (funding), or patient/physician preference. Most patients on VKA have their family physicians manage their oral anticoagulants. On average, the time in therapeutic range achieved by family physicians is low (50-55%). There is also a number of patients who have no family physician and are either taking VKA without monitoring, or are having their anticoagulants monitored routinely though emergency room physicians/visits. The Ottawa Hospital (TOH) anticoagulation management service is an e-health solution that offers patients world beating time in therapeutic range (TIR). TOH uses a pharmacy managed DAWN software package (computer-assisted warfarin dosing program). Maintaining patients in therapeutic range for a high percentage of time (greater than 70%) can reduce the risk or recurrent thrombosis (venous or arterial) from under-anticoagulation and the risk of bleeding complications from over-anticoagulation. Well managed VKA therapy has also been suggested to be as safe as therapy with novel oral anticoagulants in some subgroup analysis of studies investigating the novel oral anticoagulants. Objectives/Methods: The purpose of this study was to bring the benefits of the TOH experience to provide a Regional Anticoagulation Management Service across a wide region of eastern Ontario, Canada. This service includes remote blood testing (at a lab near the patient’s home), integrated LIS link to a computerized dosing system (possible through a commercial lab partnership), and communication of dosing and testing instructions via interactive voice recognition (IVRS), email, or live (pharmacist/pharmacist assistant). We administered a patient satisfaction survey to a sample of 111 patients enrolled in the service as well as reported TIR for patients enrolled in our service during the study period (2009-2011). Results: At the beginning of the study, 1400 patients were enrolled in the program. After 2 years, the number has increased to by 66% to 2325. The average TIR for patients in the program as of October 2011 was 76.3% (overall), 77.8% (IVRS), 76.8% (email), and 73.3% (live). The patient satisfaction survey demonstrated that 94% patients prefer VKA anticoagulation monitoring through TOH service compared to their previous experience. 84% patients either satisfied or very satisfied with VKA anticoagulation care through TOH service (compared to 53% satisfaction with anticoagulant care prior to enrolling in our program). Conclusions: The TOH model of anticoagulation management service results in excellent VKA monitoring (high TIR) for a large number of patients across a wide geographical area, as well as a high level of patient satisfaction. This service allows for the safe and efficient management of VKAs in patients in whom VKA therapy is indicated. Disclosures No relevant conflicts of interest to declare.

Evaluation of Differences in Percentage of International Normalized Ratios in Range Between Pharmacist-Led and Physician-Led Anticoagulation Management Services

Background: The safety and efficacy of warfarin depend on maintaining the international normalized ratio (INR) in an established range. Objective: The purpose was to determine whether a coordinated pharmacist-led approach improved percentage of INRs in therapeutic range in comparison to a physician-led anticoagulation management service (AMS). Methods: A retrospective chart review was conducted for patients at a multisite primary care organization. INR data for patients receiving warfarin management by a physician were collected from December 1, 2009 to May 31, 2010. These were compared to INR results from December 1, 2010 to May 31, 2011, during which patients received warfarin management from a pharmacist. The primary end points were percentage of INRs within a goal range of 2.0 to 3.0 and an expanded goal range of 1.8 to 3.2 for the physician-led group versus the pharmacist-led group. Results: The percentage of INR results within the goal range (2.0-3.0) was greater among patients in the pharmacist-led group (n = .130) than the physician-led group (n = 96; 57.5% vs 50.0%, respectively; P = .0004). The percentage of INR results <1.5 (7.3% vs 5.1%) and >3.5 (11.4% vs 7.1%) was also statistically significant in favor of the pharmacist-led AMS, with P values of .03 and .0004, respectively. Conclusion: A pharmacist-led AMS improved the percentage of INRs in range, with significantly less out-of-range results.