Assessment of Non-vitamin K Oral Anticoagulants Use in a Tertiary Care Center in the USA: A Chart Review of 909 Patients.

BACKGROUND: Non-vitamin K oral anticoagulants (NOACs) have emerged as an attractive alternative to vitamin K antagonists for various thromboembolic indications. However, prescribed NOAC doses are often inconsistent with drug labeling and prescribers might not consider the potential risks associated with concomitant use of other drugs, which can compromise NOACs' safety and effectiveness. METHODS: A retrospective chart review was conducted in a tertiary care center in USA over a 4-month period. We studied patients whose home medications included NOACs and assessed the appropriateness as per drug labeling, taking into consideration relevant clinical factors and concomitant drug intake. RESULTS: A total of 909 patients with a mean age of 70.6 ± 13.1 years, out of which 51.6% were males, were included. The majority of patients received NOACs for stroke prevention in atrial fibrillation (AF) (70.5%), or deep venous thrombosis/pulmonary embolism (DVT/PE) treatment (13.5%). The most common drug prescribed was apixaban (57.8%) followed by rivaroxaban (34.0%), and less frequently dabigatran (7.7%). Inappropriate dosing was significantly more frequent among older patients, those taking NOACs for AF, those taking a higher number of home medications, and those with a lower creatinine clearance. Seven hundred and six patients (77.67%) had at least one drug-NOAC interaction, out of which 515 were rated major interactions. Antiplatelets, amiodarone, non-steroidal anti-inflammatory medications, and calcium channel blockers were the most commonly interacting drugs. CONCLUSION: A significant number of patients received NOACs at doses inconsistent with the package labeling or had clinically significant drug-drug interactions with NOACs. Efforts are warranted to improve appropriate dosing and avoid significant drug interactions.