Evaluation of Direct Oral Anticoagulant Dosing and Monitoring in Two Geriatric Outpatient Clinics

OBJECTIVE: This study was conducted to evaluate direct oral anticoagulants (DOACs) prescribed to elderly patients in an outpatient setting, specifically evaluating if Food and Drug Administration (FDA) -approved dosing recommendations are followed.
DESIGN: This study was a retrospective quality improvement project.
SETTING: This study was conducted at geriatric hospital-based primary care clinics at the University of Pittsburgh Medical Center (UPMC), UPMC Senior Care Institute and UPMC Benedum Geriatric Center.
PATIENTS: Subjects included were 65 years of age or older; had an office visit at UPMC Senior Care Institute or UPMC Benedum Geriatric Center from September 1, 2015, to August 31, 2017; and had a DOAC on their home medications.
INTERVENTIONS: Data were obtained through retrospective chart review.
MAIN OUTCOME MEASURE: The primary objective of the study was to evaluate the appropriateness of dosing of DOACs based on FDA-labeled recommendations.
RESULTS: Of 232 patients included in analysis, 42.7% were found to have dosing inconsistent with FDAlabeled recommendations (47.3% apixaban, 35.8% rivaroxaban, and 31.6% dabigatran). No patients were prescribed edoxaban. The majority (72.7%) were dosed lower than FDA-recommended doses. Of all patients, the most frequent parameter (54.5%) for inappropriate dosing was patients meeting only 1 of 3 dose-reduction criteria when prescribed reduced-dose apixaban. Geriatrician and nongeriatrician prescribers had similar rates of prescribing DOACs with doses inconsistent with FDA-labeled recommendations (44.0% vs. 40.8%; P = 0.62).
CONCLUSION: Results suggest that DOACs used in outpatient geriatric patients are frequently dosed inconsistent with FDA-approved dosing recommendations. Further research is needed regarding clinical outcomes in older patients receiving DOACs and in those with dose adjustments inconsistent with FDA-labeled recommendations.