Assessment of Population-Based Approach to Direct Oral Anticoagulant Management.

Background: As preferences for oral anticoagulation shift from warfarin to direct oral anticoagulants (DOACs), a new care management model is needed. A population approach leveraging a DOAC Dashboard was implemented to track all patients on a DOAC followed by a physician at an academic medical center. The DOAC Dashboard is a real-time report within the electronic health record (EHR) that identifies patients who require evaluation for DOAC dose/therapy adjustment due to changing renal function, age, weight, indication, and/or significant drug-drug interaction (DDI). Objective: This study aims to describe the initial phase of DOAC Dashboard implementation, to evaluate the effectiveness of interventions, and to assess a multidisciplinary approach to management. Method: Retrospective descriptive study of the DOAC Dashboard from August 22, 2019, to January 20, 2022. Primary outcomes include total number of alerts addressed and interventions needed. Secondary outcome is the proportion of interventions implemented by the prescribing clinician. Result: A total of 10 912 patients were identified by the DOAC Dashboard at baseline. A total of 5038 alerts were identified, with 668 critical alerts, 3337 possible critical alerts, and 1033 other alerts. Pharmacists addressed 1796 alerts during the study period (762 critical alerts and 1034 possible critical). Critical alerts included 62 significant DDI, 379 inappropriate dosing, and 321 others. Of the critical alerts, intervention was needed in 291 cases (38%), with 255 (88%) of proposed interventions implemented. Critical alerts and possible critical alerts not requiring intervention were resolved by data entry. Conclusion: The DOAC Dashboard provides an efficient method of identifying patients on DOACs that require dose adjustments or therapeutic modifications.

Proportion of Patients on Warfarin Therapy Who Are Eligible for Conversion to a Direct Oral Anticoagulant in the Setting of COVID-19.

BACKGROUND: Warfarin, a commonly prescribed anticoagulant, requires frequent lab monitoring. Lab monitoring puts patients at risk of COVID-19 exposure and diverts medical resources away from health care systems. Direct oral anticoagulants (DOACs) do not require routine therapeutic monitoring and are indicated first line for nonvalvular atrial fibrillation (NVAF) stroke prevention and venous thromboembolism (VTE) prevention/treatment. OBJECTIVE: The purpose of the study was to determine the proportion of patients who qualify for DOACs and assess for predictors of qualification. METHODS: This cross-sectional study investigated patients on warfarin managed by Michigan Medicine Anticoagulation Service. Direct oral anticoagulant eligibility criteria were established using apixaban, dabigatran, and rivaroxaban package inserts. Patient eligibility was determined through chart review. The primary outcome was the proportion of patients who qualify for DOACs based on clinical factors. Predictors of DOAC qualification were assessed. RESULTS: This study included 3205 patients and found 51.8% (n = 1661) of patients qualified for DOACs. Qualifying patients were older (71.9 vs 59.4 years, P < 0.0001) with a higher CHA2DS2 VASc (3.7 vs 3.4, P < 0.0007). The primary disqualifying factor was extreme weight, high and low. Accounting for a patient's sex and referral source, age > 65 (odds ratio [OR] = 1.9, P < 0.0001) and NVAF indication (OR = 5.6, P < 0.0001) were significant predictors for DOAC qualification. CONCLUSION AND RELEVANCE: Approximately 52% of patients on warfarin were eligible for DOACs. This presents an opportunity to reduce patient exposure to health care settings and health care utilization in the setting of COVID-19. Increased costs of DOACs need to be assessed.

Management of anticoagulation in patients with human immunodeficiency virus/acquired immunodeficiency virus.

PURPOSE: Limited guidance is available to assist practitioners in managing complex human immunodeficiency virus (HIV) related pharmacotherapy. Management recommendations of oral anticoagulation (warfarin and direct oral anticoagulants [DOACs]) and highly active antiretroviral therapy (HAART) based on drug-drug interactions (DDI) studies and pharmacokinetic (PK) data are provided. METHODS: Search of PubMed, EMBASE, and Google Scholar (01/1985 to 12/2018) using the terms "HIV," "DDI," and names of HAART. PK information and DDI screening were obtained from medication package inserts and drug information resources: Micromedex, Lexicomp, HIV-DDI Checker- University of Liverpool. All English literature on DDI or PK interactions was considered for inclusion. In the absence of data, PK principles were used to predict the likelihood of interactions. RESULTS: No clinically significant DDI are expected to occur between DOACs and nucleoside or nucleotide reverse transcriptase inhibitors (NRTIs), maraviroc, enfuvirtide, or integrase strand inhibitors (INSTIs) that do not include a pharmacologic booster. Potent cytochrome P (CYP) 450 enzyme inhibition by protease inhibitors (PIs) or pharmacologic boosters may lead to higher concentrations of the DOAC and potentially increase the risk of bleeding. CYP450 enzyme induction by non-nucleoside reverse transcriptase inhibitors (NNRTIs) may lower concentrations of DOACs, which may lead to treatment failure. Warfarin DDIs are variable, therefore close monitoring of the INR is recommended. CONCLUSIONS: The potential for DDIs between HAART and oral anticoagulation exists based on PK profiles. Management of these interactions should involve careful selection based on patient characteristics and HAART and anticoagulants with a low potential for DDI should be selected.

Clinical Safety Outcomes in Patients With Nonvalvular Atrial Fibrillation on Rivaroxaban and Diltiazem.

BACKGROUND: It is unknown whether diltiazem, a moderate cytochrome P450 enzyme (CYP3A4) and P-glycoprotein (P-gp) inhibitor, increases the incidence of bleeding events in combination with rivaroxaban, a CYP3A4 and P-gp substrate. OBJECTIVE: To assess major and clinically relevant nonmajor (CRNM) bleeding outcomes in patients with nonvalvular atrial fibrillation (NVAF) on rivaroxaban with concomitant diltiazem in a real-world setting. METHODS: This retrospective case-cohort study included adult patients with NVAF prescribed both rivaroxaban and diltiazem for at least 30 days. Patients were matched 1:1 by age and baseline creatinine clearance (CrCl) to control patients taking rivaroxaban alone. The primary outcome was the composite of major and CRNM bleeding. Additional outcomes included bleeding events resulting in discontinuation of rivaroxaban, time to first bleeding event, and type of first bleed. RESULTS: A total of 143 cases and 143 controls were included. The mean age was 69 years and median baseline CrCl was 87 mL/min. Median follow-up time was 12.4 months for cases and 16.5 months for controls. There was no significant difference in proportion of patients experiencing a major and/or CRNM bleeding event between cases and controls: 23.1% versus 28.0%, respectively; 9 cases and 8 controls permanently discontinued rivaroxaban because of bleeding. Gastrointestinal/rectal bleeding and hematuria were the most frequently reported bleeding events in both groups. Conclusion and Relevance: This is the first study to assess major and CRNM bleeding outcomes in patients with NVAF on rivaroxaban and diltiazem. Diltiazem use was not associated with an increased rate of bleeding events.

Peri-Procedural Management of Oral Anticoagulants in the DOAC Era.

Peri-procedural management of oral anticoagulants can be complex and confusing for many providers. It involves a careful balance of a patient's thromboembolic risk and bleeding risk. For every patient chronically taking an oral anticoagulant who will be undergoing an elective procedure, a four step approach may be considered when creating a plan for the oral anticoagulant. (1) Does the oral anticoagulant need to stop for the procedure? (2) If yes, when should the oral anticoagulant be stopped pre-procedure? (3) Does the patient require a "bridging" parenteral anticoagulant? (4) When should anticoagulation be re-started post procedure? Based on the unique features of warfarin versus the direct oral anticoagulants (DOAC), a unique, personalized plan should be developed and tailored to the individual patient. Anticoagulant specialists, such as anticoagulation clinic pharmacists, may help facilitate this process.