Quality of clinical direct oral anticoagulant prescribing and identification of risk factors for inappropriate prescriptions

Role of Clinical Pharmacy anticoagulation service on Apixaban prescribing appropriateness in atrial fibrillation in Saudi Arabia

BACKGROUND

Inappropriate DAOC dosing is precuarious and frequently encountered. Apixaban is the most reported DOAC to be inappropriately dosed. We examined the effect of adding a Clinical Pharmacist to the cardiology team rounds to the standard practice in Apixaban prescription patterns in a tertiary center in KSA.

OBJECTIVE

To determine the effect of clinical pharmacy services on Apixaban dose appropriateness upon discharge in Atrial Fibrillation patient pobulation.

METHODS

This is a single-center, retrospective cohort of patients with atrial fibrillation using a quasi-experiment of pre-post design to evaluate Apixaban dose appropriateness using clinical pharmacy services. Clinical pharmacist was added to the team to evaluate and change the regimen according to FDA dosing. Data were collected for 9 months for each, patients were followed up for efficacy and safety outcomes for 1 year.

RESULTS

A total of 550 patients were initially collected after follow-up, the number of patients was in the pre-phase cohort (NO CCP; n= 112) from July 2018 to the March 2019 and compared to post phase cohort (CCP, n=103) from July 2019 to March 2020. 215 Patients were included, For primary end point, CCP cohort had significantly appropriate prescriptions of apixaban compared to Non-CCP (90.2 % vs 71.5 %, p<0.001)., no differences in thromboembolic and hemorrhagic adverse events betewwn 2 cohorts.

CONCLUSION

A multidisciplinary team approach including clinical pharmacy services is effective in increasing the appropriate use of Apixaban upom discharge without apparent increased risk of bleeding or Adverse events.

Exploring the pharmacists' role in optimising antithrombotic therapy in primary care: a qualitative study

OBJECTIVE

In antithrombotic therapy, the balance between efficacy and safety is delicate, which makes it challenging for healthcare professionals, including pharmacists, to optimise therapy. Pharmacists may play an important role in optimising antithrombotic therapy, but especially in primary care, this role has not been elucidated. Here, we study how community pharmacists (pharmacists in primary care) perceive their current and future role in antithrombotic therapy.

DESIGN

We conducted a qualitative study using semi-structured interviews. The interview protocol and subsequent analysis were based on the Theoretical Domains Framework, and the findings were interpreted with the Capability Opportunity Motivation - Behaviour System.

SETTING AND PARTICIPANTS

The interview participants were community pharmacists, located across the Netherlands, from the Utrecht Pharmacy Practice network for Education and Research.

RESULTS

We interviewed 16 community pharmacists between February and August 2021 and identified several major themes which were important for the pharmacist's role in antithrombotic therapy. Pharmacists felt responsible for the outcome of antithrombotic treatment and intended to invest in their role in antithrombotic therapy. Pharmacists did, however, experience barriers to their role in antithrombotic therapy, like a lack of access to clinical information such as the indication of antithrombotic treatment and a lack of specific knowledge on this treatment.

CONCLUSION

Community pharmacists perceive a role for themselves in antithrombotic therapy. To fulfil this role, several preconditions must be met.

Prolonged Secondary Stroke Prevention with Edoxaban: A Long-Term Follow-Up of the SATES Study

BACKGROUND

Little evidence is available on the long-term efficacy and safety of edoxaban, mainly due to the recent release date. The primary objective of the study was to evaluate the safety of edoxaban, defined by the incidence of major bleedings. We then aimed to evaluate the incidence of thromboembolic events and the persistence of edoxaban therapy in the long-term.

METHODS

In this observational cohort study, we included ischemic stroke patients enrolled in a previous study to evaluate the safety and efficacy of long-term edoxaban treatment. Data were collected by a trained investigator through a structured telephone interview.

RESULTS

Sixty-three subjects (median age 81.0 (73.5-88.0) years, 38.1% male) were included in the study, with a mean follow-up of 4.4 ± 0.7 years (range: 3.2-5.5 years). Only one patient (1.6%, 0.4%/year) presented a major extracranial bleeding, and none had cerebral hemorrhage. Six thromboembolic events occurred in five patients (7.9%): three recurrent strokes, two transient ischemic attacks, and one myocardial infarction (2.2%/year). Over a follow-up period of more than three years, 13 patients discontinued edoxaban (20.6%). Conclusions: Edoxaban seems to be effective and safe in the long-term. The persistence rate of edoxaban therapy is optimal after more than three years of treatment.

Inappropriate prescriptions of direct oral anticoagulants (DOACs) in hospitalized patients: A narrative review

Direct oral anticoagulants (DOACs) have become the cornerstone for prevention of thromboembolic events in patients with atrial fibrillation and patients with a history of venous thromboembolism. However, studies show that DOAC prescriptions are commonly inconsistent with guideline recommendations. DOAC dosing in the acutely ill patient could impose an even greater challenge. In this review, we describe the prevalence of inappropriate inpatient prescribing of DOACs and the associated rationales, predictors and clinical consequences. With the aim of promoting appropriate prescriptions of DOACs to hospitalized patients, we further outline DOAC dose reduction criteria justified by various guidelines, illustrating the complexities of appropriate dosing, especially in acutely ill patients. Moreover, we will discuss the impact of anticoagulant stewardship programs and the vital role that pharmacists may play in optimizing inpatient DOAC treatment.

Characteristics of patients with atrial fibrillation treated with direct oral anticoagulants and new insights into inappropriate dosing: results from the French National Prospective Registry: PAFF

AIMS

Since the introduction of direct oral anticoagulant (DOAC) for atrial fibrillation (AF) therapy, inappropriate and/or underdosing of these drugs has been a major clinical challenge. We evaluated the characteristics of patients with AF treated with inappropriate and low-dose DOACs.

METHODS AND RESULTS

Patients with AF treated with inappropriate and low-dose DOACs from October 2021 to December 2021 were evaluated from the French National Prospective Registry (PAFF). We evaluated 1890 patients with AF receiving DOACs (apixaban 55%, dabigatran 7%, and rivaroxaban 38%). Inappropriate dosing was noted in 18% of the population. Patients with appropriate dosing had less comorbidities: younger age (75 ± 10 vs. 82 ± 8 years old, P < 0.0001), reduced chronic renal failure (26 vs. 61%, P < 0.0001), and lower CHA2DS2VASc and HASBLED scores (3 ± 2 vs. 4 ± 3, P < 0.0001; 2 ±1 vs. 2 ± 2, P < 0.0001), respectively. In multivariate analysis, older age (P < 0.0001) and a higher CHA2DS2VASc score (P = 0.0056) were independently associated with inappropriate DOAC dosing. Among 472 patients (27%) treated with low-dose rivaroxaban or apixaban, 46% were inappropriately underdosed. Patients inappropriately underdosed were younger (82.3 ± 8.4 vs. 85.9 ± 5.9 years, P < 0.0001) with less chronic renal disease (47 vs. 98%, P < 0.0001). However, these patients had higher rates of prior haemorrhagic events (18 vs. 10%, P = 0.01), clopidogrel use (11 vs. 3%, P = 0.0002), and apixaban prescription (74 vs. 50%, P < 0.0001).

CONCLUSION

Within this large registry, DOACs were associated with inappropriate dosing in 18% of cases. Independent predictors of inappropriate dosing were high CHA2DS2VASc scores and older age. Moreover, 46% of patients treated with low-dose DOACs were inappropriately underdosed and more frequently in patients treated with apixaban.

Prevalence and predictors of inappropriate dosing of direct oral anticoagulants

BACKGROUND

Information on inappropriate dosing of direct oral anticoagulants (DOACs) is scarce in the Australian context.

AIM

To describe the prevalence and potential predictors of inappropriate dosing of DOACs.

METHODS

Patients who received DOACs during admission under a general medical unit over a 2-year period (from January 2017 to December 2018) were retrospectively studied. Appropriateness of the dosing regimen was verified against the recommendations of the Therapeutic Goods Administration of Australia. Data were obtained from medical records and analysed in univariate and multivariate logistic regression models. The variables associated with under- and overdosing were also determined.

RESULTS

A total of 203 (mean age 71.6 ± 14.5 years, females 52%) patients were studied. Inappropriate dosing occurred in 44 (22%) patients: underdosing 27 (13%) and overdosing 17 (8%). Age ≥75 years (P < 0.01), lower estimated creatinine clearance (CrCl) (P < 0.01), prescription of DOAC prior to index admission (P < 0.01) and higher Charlson Comorbidity Index (P < 0.01), HAS-BLED (P < 0.01) and CHA2 DS2 -VASc (P < 0.01) scores had a significant univariate association with inappropriate dosing. However, in the multivariate logistic regression only lower CrCl (odds ratio (OR) 1.04, 95% confidence interval (CI): 1.01-1.07, P < 0.01) and prescription of DOAC prior to index admission (OR 2.62, 95% CI: 1.01-6.75, P = 0.047) remained significantly associated with inappropriate dosing. Impaired renal function also had a significant association with underdosing (OR 1.04, 95% CI: 1.01-1.07, P = 0.01) and borderline significance with overdosing (OR 1.03, 95% CI: 1.00-1.07, P = 0.06).

CONCLUSION

Inappropriate dosing of DOACs, especially underdosing, is common in clinical practice. Clinicians should exercise due diligence when prescribing DOACs to patients with renal impairment and in outpatient settings.

Anticoagulation stewardship: Descriptive analysis of a novel approach to appropriate anticoagulant prescription

Background

Anticoagulants are a leading cause of morbidity among hospitalized patients, with prescription errors commonly reported. Literature surrounding anticoagulation stewardship is scarce despite its documented effectiveness in the antimicrobial realm.

Objective

To determine the proportion of accepted recommendations on inappropriate anticoagulant prescriptions suggested by a multidisciplinary anticoagulation stewardship program (ASP).

Methods

We conducted a descriptive cohort study of hospitalized patients using therapeutic anticoagulation at a large Canadian tertiary care center between September 1, 2019, and February 28, 2020. A multidisciplinary ASP, composed of physicians and pharmacists, was implemented on June 1, 2019. Patient-, anticoagulant-, and admission-related characteristics were collected. The primary outcome was the proportion of accepted ASP team recommendations by the prescribing team.

Results

A total of 381 patients were enrolled during the study period, resulting in 553 anticoagulant reviews (1.56 reviews/patient) by the ASP. The most common indications for anticoagulation were atrial fibrillation (n = 276, 72%) and venous thromboembolism (n = 84, 22%). Direct oral anticoagulants were most frequently prescribed (n = 253, 67%), followed by vitamin K antagonists (n = 88, 23%). Among the reviewed prescriptions, 355 of 553 (64%) generated a recommendation; 299 of 355 (84%) recommendations were accepted by the treating team. Dose adjustments were the leading category of recommendations (31%), followed by alerts regarding drug interactions (19%).

Conclusion

Inpatient anticoagulant prescriptions were optimized following recommendations by the ASP team. The most frequent types of prescription changes concerned dose adjustments and drug interactions. Further research is required to assess the effect of an ASP on clinical outcomes.

Management of combined oral antithrombotic therapy by an Antithrombotic Stewardship Program: a prospective study

AIMS

Antithrombotic management initiatives could prevent inappropriate prescribing and improve patient outcomes especially in patients on combined antithrombotic therapy. To investigate this, a multidisciplinary antithrombotic stewardship program (ASP) was implemented in our hospital. The primary aim of this study was to determine the efficacy of this ASP by assessing the number of patients on combined antithrombotic therapy for whom one or more interventions were needed.

METHODS

A prospective cohort study in a large teaching hospital was conducted. Hospitalized patients were included who received combined antithrombotic therapy in which an oral anticoagulant was combined with one (double therapy) or two (triple therapy) platelet aggregation inhibitors. The ASP proactively evaluated the appropriateness of this combined antithrombotic therapy. If needed, ASP improved the concerned therapy. Each improvement measurement recommended by the ASP was counted as one intervention.

RESULTS

A total of 460 patients were included over a period of 12 months. 251 (54.6%) patients required at least one intervention from the ASP. The most common interventions were: 1) to define and document the maximum duration of the combined antithrombotic therapy needed instead of lifetime use of the combination (65.5%), 2) to discontinue antithrombotic therapy as the proper indication was lacking (19.4%), and 3) to adjust the dosage (8.1%).

CONCLUSION

An intervention was needed in more than half of the patients on combined antithrombotic therapy. Implementation of an dedicated ASP evaluating combined antithrombotic therapy improves the use and safety of antithrombotic medication.

Choice of oral anticoagulant prescribed by general practices in Wales: Application of Dirichlet regression and linked data

Aims

There has been sustained growth in the prescribing of direct oral anticoagulants (OACs) in primary care in the UK. Given the different indications, properties and prices of OACs, variation between prescribers is expected; however, a high level of variation may be evidence of inappropriate or suboptimal prescribing. This study examined the variation in the relative use of OACs in primary care in Wales.

Methods

Data on total defined daily doses of all community‐dispensed OACs in 2019 were linked at the GP practice level with disease registers, patient demographic data and GP and patient numbers. The relative use of each OAC, as a fraction of all OACs prescribed, was analysed using Dirichlet regression to quantify the association between prescribing patterns and practice and area‐level characteristics.

Results

Across 417 GP practices, the mean (range) in the relative prescribing of warfarin was 37% (6%–64%), apixaban was 32% (2%–65%), rivaroxaban 23% (0%–66%), dabigatran 3% (0%–23%) and edoxaban 6% (0%–59%). Statistical modelling provided strong evidence that prescribing patterns are associated with a GP practice's health board and also their nearest major hospital. Compared to the null model, a model including health board resulted in a 15% fall in Akaike information criterion, increasing to 20% with the addition of nearest major hospital and 27% including further covariates.

Conclusion

Systematic variation in OAC prescribing, by health board and based on nearest hospital, indicates that factors other than patient clinical characteristics and preferences may be influencing prescribing decisions.

Appropriateness of inpatient dosing of direct oral anticoagulants for atrial fibrillation

Direct oral anticoagulant (DOAC) use for stroke prevention in atrial fibrillation (AF) has dose reduction criteria including age, weight, serum creatinine, and creatinine clearance. There is a paucity of data for rates of inappropriate inpatient DOAC dosing in Australia. The objective was to determine the rates of inappropriate inpatient DOAC dosing in AF and identifying its associated underlying factors. We conducted a retrospective cross-sectional study from December 2013 to November 2019 across six South Australian public hospitals utilising a centralised electronic health record. Multivariate analysis was used to identify factors associated with underdosing of patients prescribed apixaban. Of 1882 inpatients, 544 (28.9 %) were inappropriately dosed. Underdosing was the most common form of inappropriate dosing with rates of 22.9 % (n = 295), 7.1 % (n = 7), and 25.1 % (n = 124) for apixaban, dabigatran, and rivaroxaban, respectively. Independent factors predictive of apixaban underdosing included higher age (adjusted odds ratio (aOR) 1.63 [95 % Confidence Interval (CI): 1.47-1.81]), higher serum creatinine (aOR 1.13 [95 % CI: 1.08-1.19]), higher total number of drugs on discharge (aOR 1.08 [95 % CI: 1.04-1.11]), and being already prescribed a DOAC on admission (aOR 1.63 [95 % CI: 1.12-2.38]). Nearly one quarter of all apixaban prescribing was inappropriately underdosed. Older patients with multimorbidity, frailty and polypharmacy present a challenge for clinicians in balancing risks of thromboembolism and bleeding. It is likely prescribers are more conservative in their apixaban dosing in this population. Clinicians should consider alternative drug regimens to avoid DOAC use at inappropriate doses at unknown safety and efficacy.

Quantification of direct-acting oral anticoagulants: Application of a clinically validated liquid chromatography-tandem mass spectrometry method to forensic cases

In certain forensic cases, a quantification of direct-acting oral anticoagulants (DOACs) can be necessary. We evaluate the applicability of a previously described liquid chromatography-tandem mass spectrometry (LC-MS/MS) methodology for the determination of DOACs in plasma to postmortem specimen. Postmortem internal quality control (PIQC) samples were prepared in pooled blank postmortem heart blood, femoral blood, cerebrospinal fluid (CSF), and urine as well in plasma. To examine the application of the clinical method to forensic cases, the main validation parameters were reinvestigated using PIQC samples. Postmortem samples of 12 forensic cases with evidence of previous rivaroxaban intake and unknown bleeding disorders were analyzed. Interday variability remained within the acceptance criterion of ±15%. Matrix effects were comparable in blank plasma and postmortem matrix extracts. After 4 weeks of storage in the refrigerator, no relevant decrease of DOACs was evident. After 96 h of storage at room temperature, a slight decrease in edoxaban concentration was observed in CSF and urine, while plasma edoxaban decreased by about 50%. Median (range) rivaroxaban concentrations determined in specimen of forensic cases were as follows: heart blood (n = 6), 17.2 ng/ml (<LOQ, 56.6 ng/ml); femoral blood (n = 12), 27.6 ng/ml (<LOQ, 110.5 ng/ml); CSF (n = 7), 11.7 ng/ml (<LOQ, 17.5 ng/ml); urine (n = 6), 275.7 ng/ml (14.5-870.9 ng/ml). The median heart/femoral blood rivaroxaban ratio was 1.2 (n = 5). Exemplary, a forensic case with detection of edoxaban in femoral blood, CSF, and urine, is presented. DOACs can be detected in postmortem heart and femoral blood, CSF, and urine specimen by LC-MS/MS. Based on limited forensic cases, no significant redistribution was evident for rivaroxaban, which was found at highest concentrations in urine.

Quality of clinical direct oral anticoagulant prescribing and identification of risk factors for inappropriate prescriptions

AIMS

Even though the use of direct oral anticoagulants (DOACs) is safe based on clinical outcomes, drug safety also depends on appropriateness of drug prescription, which is challenging for DOACs since many patient factors need to be considered. The aim of this study was to assess the appropriateness of DOAC prescriptions and to identify risk factors of determinants for inappropriate DOAC prescriptions.

METHODS

A retrospective study in a nonuniversity teaching hospital was performed of hospitalized patients (≥18 years) who received an initial DOAC prescription between February and August 2018. Appropriateness of prescribing was evaluated on 8 criteria by using a modified version of the medication appropriateness index.

RESULTS

A total of 770 initial DOAC prescriptions of inpatients were evaluated: 267 patients (34.6%) had at least met 1 inappropriate criterion for a DOAC prescription. The most frequent inappropriate criterion was dosage (17.4%). Of the 4 DOACs, dabigatran (21.6%) and apixaban (21.2%) were mostly inappropriate dosed. In a multivariable analysis, reduced renal function (estimated glomerular filtration rate <50 mL/min; odds ratio [OR] = 2.35; P < .001), a diagnosis of atrial fibrillation (OR = 1.87; P = .004), and 'prescribed by surgeons' (OR = 1.9; P = .013) were independently associated with inappropriateness of prescribing.

CONCLUSION

This study has highlighted a high degree of inappropriate prescribing of DOACs. These results underline the need for targeted interventions to improve DOAC prescribing.