Identification of risk factors for inappropriate and suboptimal initiation of direct oral anticoagulants

Abstract

Direct Oral Anticoagulants (DOACs) require specific dosing and monitoring to ensure safe and appropriate use. The purpose of this evaluation was to identify patient- and process-related factors that correlate with increased risk of inappropriate prescribing of DOACs. A retrospective chart review was conducted in three outpatient clinics within an academic medical center to identify patients started on DOAC therapy and evaluate the appropriateness of DOAC initiation. Data collected included patient demographics, DOAC medication initiated, dose, indication, baseline laboratory values, concomitant medications, type and specialty of prescriber, and initiation setting. Appropriateness of initial dose was assessed and data were analyzed in order to identify factors correlating with inappropriate use. One-hundred sixty-seven patients initiated on a DOAC were identified. Most patients were prescribed anticoagulation for atrial fibrillation (74.9 %) and most commonly prescribed rivaroxaban (62.9 %). An inappropriate dose was prescribed in 24 (14.4 %) patients. Female patients and patients over 75 years were more likely to be prescribed an inappropriate initial dose. Baseline evaluation of blood counts and organ function were often not performed: hemoglobin values had not been drawn within the month prior to initiation in 28.7 % of patients, serum creatinine in 22.8 %, alanine transaminase in 52.1 %, and total bilirubin in 64.1 %. Lack of baseline labs was more pronounced in patients initiated on a DOAC in the outpatient setting. Dosing and baseline lab collection for DOAC initiation were suboptimal in all settings analyzed. Targeted interventions are needed to ensure the safe and appropriate use of DOAC therapy.

Appropriateness of DOAC Prescribing Before and During Hospital Admission and Analysis of Determinants for Inappropriate Prescribing

“…Inappropriate dosing rates in AF patients varied from 7.7 to 42.0% for dabigatran, from 13.0 to 29.8% for rivaroxaban, and from 12.7 to 48.1% for apixaban. Other studies, including a mix of AF and VTE patients, such as the present study, showed similar results (Armbruster et al, 2014 ; Larock et al, 2014 ; Pattullo et al, 2016 ; Howard et al, 2017 ; Whitworth et al, 2017 ). Dosing appropriateness in these studies was evaluated based on the SmPC or the medication appropriateness tool (MAI).…”

“…Several studies have reported a poor adherence rate with dosing guidelines for the DOACs regardless of the renal function. These data suggest that inappropriate DOAC dosing is common and varies from 12.8 to 34.0% of adult hospitalized AF patients as well as other patients taking a DOAC (Armbruster et al, 2014 ; Larock et al, 2014 ; Kucey et al, 2016 ; Pattullo et al, 2016 ; Steinberg et al, 2016 ; Basaran et al, 2017 ; Howard et al, 2017 ; Shrestha et al, 2017 ; Whitworth et al, 2017 ).…”

Appropriateness of oral anticoagulant therapy prescription and its associated factors in hospitalized older people with atrial fibrillation

“…Even if the NOACs are marketed as having simplified dosing as compared with that for warfarin, the appropriate dose of these agents is dependent on several patient-specific factors, such as age, weight, baseline renal and hepatic impairment and concomitant drug use [16]. As shown in a previous study, in which the majority of patients on an inappropriate dose of OAC were found to be on a lower dose than recommended [25], we also found that most errors were due to unnecessarily reduced doses. This is probably due to the fact that it has been shown that lower doses are associated with a reduction in the risk of major bleeding [26].…”

Incorporating Comprehensive Management of Direct Oral Anticoagulants into Anticoagulation Clinics

“…No dose adjustment information is provided for dabigatran in regard to hepatic impairment . One small study of 167 patients receiving DOACs found that hepatic function tests were most frequently omitted from monitoring, relative to serum creatinine and hemoglobin . Thus poor consistency with regard to laboratory monitoring may represent an unmet need that can be fulfilled by ongoing DOAC monitoring.…”