PCV135 - NON-VITAMIN K ANTAGONIST ORAL ANTICOAGULANTS PRESCRIPTION MONITORING: HOW TO OPTIMIZE VIGILANCE IN STROKE PREVENTION

Abstract

Non-vitamin K antagonist oral anticoagulants (NOACs) are prescribed to patients with atrial fibrillation (AF) to reduce the risk of stroke. Prescribing the correct NOAC dose warrants careful consideration with the prevailing dose criteria that differ per NOAC. Electronic systems are useful to intercept prescriptions that are incorrect based on simple ‘primary’ criteria, for example the dosing frequency and drug-drug interactions with concomitant medication. However, these systems do not take into account patient characteristics such as age, renal function or weight which are crucial elements to determine the dose of NOACs. Our goal was to retrospectively determine the appropriateness of all electronic in-hospital prescriptions. Atrial Fibrillation patients with a primary NOAC prescription between January 2012 – December 2016, inpatient and outpatient, were identified from our electronic hospital information system (Martini Hospital, Groningen, The Netherlands). Appropriateness was determined, as compared to the product labelling approved by the European Medicines Agency, to address common pitfalls in prescribing NOACs and to identify targets for population-based prescription monitoring. The study included 3231 AF patients that initiated a NOAC, of which 10.7% had an inappropriate dose and the appropriateness of the prescription could not be determined in 14.1%. The most frequent reason for unknown appropriateness was an unknown renal function (13.9% of all patients). Apixaban, dabigatran and rivaroxaban were underdosed in 14.2% of the reduced dose prescriptions and overdosed in 4.5% of the full dose prescriptions. This study provides real-world evidence that underdosing of NOACs occurs more often than overdosing. Crucial patient-specific information to determine the correct dose is often lacking. Periodic population-based monitoring of anticoagulant prescriptions can help to achieve vigilance in stroke prevention with NOACs along the years.