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

How I treat the co-occurrence of venous and arterial thromboembolism: anticoagulation, antiplatelet therapy, or both?

ABSTRACT

Arterial and venous thromboses are classically considered distinct disease states, with arterial thrombosis mediated predominantly by platelets and therefore, treated with antiplatelet therapy, and venous thrombosis mediated by the plasmatic coagulation system and treated with anticoagulation. However, co-occurrence of arterial and venous events is common, and there is increasing evidence of shared risk factors and pathophysiologic overlap. This presents a management challenge: does the patient with venous and arterial thrombosis, require anticoagulation, antiplatelet therapy, or both? Herein, we present a structured approach to the evaluation and management of patients with venous thrombosis who are also at risk for or have a history of an arterial thromboembolic event. We emphasize the importance of defining the indications for antithrombotic therapy, as well as the evaluation of factors that influence both thrombotic and bleeding risk, including disorder-specific and patient-specific factors, as well as the inherent risk balance of antithrombotic therapy regimens. We illustrate this approach in 4 cases, discussing the unique considerations and recent updates in the management of venous thrombosis, acute noncardioembolic ischemic stroke, coronary artery disease and acute myocardial infarction, and peripheral artery disease after revascularization.

PrevAleNce and Associated factors of inappropriaTe dosing of direct Oral anticoaguLants In pAtients with Atrial Fibrillation: the ANATOLIA-AF Study

PURPOSE

Inappropriate dosing of direct oral anticoagulants is associated with an increased risk of stroke, systemic embolism, major bleeding, cardiovascular hospitalization, and death in patients with atrial fibrillation. The main goal of the study was to determine the prevalence and associated factors of inappropriate dosing of direct oral anticoagulants in real-life settings.

METHODS

This study was a multicenter, cross-sectional, observational study that included 2004 patients with atrial fibrillation. The study population was recruited from 41 cardiology outpatient clinics between January and May 2021. The main criteria for inappropriate direct oral anticoagulant dosing were defined according to the recommendations of the European Heart Rhythm Association.

RESULTS

The median age of the study population was 72 years and 58% were women. Nine-hundred and eighty-seven patients were prescribed rivaroxaban, 658 apixaban, 239 edoxaban, and 120 dabigatran. A total of 498 patients (24.9%) did not receive the appropriate dose of direct oral anticoagulants. In a logistic regression model, advanced age, presence of chronic kidney disease and permanent atrial fibrillation, prescription of reduced doses of direct oral anticoagulants or edoxaban treatment, concomitant use of amiodarone treatment, and non-use of statin treatment were significantly associated with potentially inappropriate dosing of direct oral anticoagulants.

CONCLUSION

The study demonstrated that the prevalence of inappropriate direct oral anticoagulant dosing according to the European Heart Rhythm Association recommendations was 24.9% in patients with atrial fibrillation. Several demographic and clinical factors were associated with the inappropriate prescription of direct oral anticoagulants.

Standardized direct oral anticoagulants prescription for treatment of acute venous thromboembolism in the emergency department: A quality improvement initiative

INTRODUCTION

Direct oral anticoagulants (DOACs) are commonly used for the treatment and prevention of venous thromboembolism (VTE). However, prescription errors with DOACs can lead to patient dissatisfaction and harm. This study aimed to evaluate the impact of a standardized prescription for DOACs for VTE on prescription appropriateness.

MATERIALS AND METHODS

The study included patients discharged from the Emergency Department (ED) with a DOAC prescription for an acute VTE. A standardized prescription tool was developed and implemented, and patients were divided into pre- and post-intervention groups. The appropriateness of prescriptions was assessed using the Medication Appropriateness Index (MAI).

RESULTS

A total of 161 patients with VTE were included in the study. The post-intervention group showed a significant increase in prescriptions with an MAI rating of "appropriate" and a decrease in ratings of "inappropriate." Improvements were observed in loading dose duration, maintenance dose frequency and duration, and inclusion of necessary drug coverage codes.

CONCLUSION

The implementation of a standardized prescription for DOACs in the management of VTE in the ED significantly improved medication appropriateness and reduced inappropriate prescriptions. Standardized prescriptions have the potential to enhance patient safety and optimize care by providing clear and uniform guidance to healthcare providers. Further research is needed to explore the effectiveness of medication prescription software systems in real-world clinical settings to improve prescribing practices.

Prevalence, contributing factors, and interventions to reduce medication errors in outpatient and ambulatory settings: a systematic review

BACKGROUND

Medication errors are common events that compromise patient safety. Outpatient and ambulatory settings enhance access to healthcare which has been linked to favorable outcomes. While medication errors have been extensively researched in inpatient settings, there is dearth of literature from outpatient settings.

AIM

To synthesize the peer-reviewed literature on the prevalence, nature, contributory factors, and interventions to minimize medication errors in outpatient and ambulatory settings.

METHOD

A systematic review was conducted using Medline, Embase, CINAHL, and Google Scholar which were searched from 2011 to November 2021. Quality assessment was conducted using the quality assessment checklist for prevalence studies tool. Data related to contributory factors were synthesized according to Reason's accident causation model.

RESULTS

Twenty-four articles were included in the review. Medication errors were common in outpatient and ambulatory settings (23-92% of prescribed drugs). Prescribing errors were the most common type of errors reported (up to 91% of the prescribed drugs, high variations in the data), with dosing errors being most prevalent (up to 41% of the prescribed drugs). Latent conditions, largely due to inadequate knowledge, were common contributory factors followed by active failures. The seven studies that discussed interventions were of poor quality and none used a randomized design.

CONCLUSION

Medication errors (particularly prescribing errors and dosing errors) in outpatient settings are prevalent, although reported prevalence range is wide. Future research should be informed by behavioral theories and should use high quality designs. These interventions should encompass system-level strategies, multidisciplinary collaborations, effective integration of pharmacists, health information technology, and educational programs.

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.

Prevalence and clinical predictors of inappropriate direct oral anticoagulant dosage in octagenarians with atrial fibrillation

PURPOSE

Older age is associated with inappropriate dose prescription of direct oral anticoagulants. The aim of our study was to describe the prevalence and the clinical predictors of inappropriate DOACs dosage among octogenarians in real-world setting.

METHODS

Data for this study were sourced from the multicenter prospectively maintained Atrial Fibrillation (AF) Research Database (NCT03760874). Of the AF patients aged ≥ 80 who received DOACs treatment, 253 patients were selected. Participants were categorized as appropriate dosage, overdosage, or underdosage. Underdosage and overdosage were, respectively, defined as administration of a lower or higher DOAC dose than recommended in the EHRA consensus.

RESULTS

A total of 178 patients (71%) received appropriate DOACs dose and 75 patients (29%) inappropriate DOACs dose; among them, 19 patients (25.6%) were overdosed and 56 (74.4%) were underdosed. Subgroup analysis demonstrated that underdosage was independently associated with male gender [OR = 3.15 (95% IC; 1.45-6.83); p < 0.001], coronary artery disease [OR = 3.60 (95% IC 1.45-9.10); p < 0.001] and body mass index [OR = 1.27 (1.14-1.41); p < 0.001]. Overdosage was independently associated with diabetes mellitus [OR = 18 (3.36-96); p < 0.001], with age [OR = 0.76 (95% IC; 0.61-0.96; p = 0.045], BMI [OR = 0.77 (95% IC; 0.62-0.97; p = 0.043] and with previous bleedings [OR = 6.40 (0.7; 1.43-28); p = 0.039]. There wasn't significant difference in thromboembolic, major bleeding events and mortality among different subgroups. Underdosage group showed a significatively lower survival compared with appropriate dose group (p < 0.001).

CONCLUSION

In our analysis, nearly one-third of octogenarians with AF received an inappropriate dose of DOAC. Several clinical factors were associated with DOACs' overdosage (diabetes mellitus type II, previous bleeding) or underdosage (male gender, coronary artery disease, and higher body mass index). Octogenarians with inappropriate DOACs underdosage showed less survival.

Prevalence, contributory factors and severity of medication errors associated with direct-acting oral anticoagulants in adult patients: a systematic review and meta-analysis

PURPOSE

This study aimed to estimate the prevalence, contributory factors, and severity of medication errors associated with direct acting oral anticoagulants (DOACs).

METHODS

A systematic review and meta-analysis were undertaken by searching 11 databases including Medline, Embase, and CINHAL between January 2008 and September 2020. The pooled prevalence of errors and predictive intervals were estimated using random-effects models using Stata software. Data related to error causation were synthesised according to Reason's accident causation model.

RESULTS

From the 5205 titles screened, 32 studies were included which were mostly based in hospitals and included DOAC treatment for thromboembolism and atrial fibrillation. The proportion of study population who experienced either prescription, administration, or dispensing error ranged from 5.3 to 37.3%. The pooled percentage of patients experiencing prescribing error was 20% (95% CI 15-25%; I² = 96%; 95% PrI 4-43%). Prescribing error constituted the majority of all error types with a pooled estimate of 78% (95%CI 73-82%; I² = 0) of all errors. The common reported causes were active failures including wrong drug, and dose for the indication. Mistakes such as non-consideration of renal function, and error-provoking conditions such as lack of knowledge were common contributing factors. Adverse events such as potentially fatal intracranial haemorrhage or patient deaths were linked to the errors but causality assessments were often missing.

CONCLUSIONS

Despite their favourable safety profile, DOAC medication errors are common. There is a need to promote multidisciplinary working, guideline-adherence, training, and education of healthcare professionals, and the use of theory-based and technology-facilitated interventions to minimise errors and maximise the benefits of DOACs usage in all settings.

PROTOCOL

A protocol developed as per PRISMA-P guideline is registered under PROSPERO ID = CRD42019122996.

Direct Oral Anticoagulants and Non-valvular Atrial Fibrillation: Compliance with Dose Level Guidelines in Patients Aged 80 Years and Over

BACKGROUND

Direct oral anticoagulants (DOACs) are currently recommended as first-line or (after vitamin K antagonists) second-line therapy for preventing stroke and systemic embolism in patients with non-valvular atrial fibrillation. In patients aged 80 years and over, however, the fear of DOAC-associated bleeding and the complexity of DOAC dosing regimes may prompt physicians to prescribe inappropriate dose levels.

OBJECTIVE

The objective of this study was to determine compliance with French and European guidelines of doses of three DOACs (apixaban, dabigatran and rivaroxaban) prescribed to patients aged over 80 years in an indication of non-valvular atrial fibrillation, and to identify factors associated with poor compliance.

METHODS

We performed a retrospective single-centre study of patients aged over 80 years routinely treated with a DOAC (apixaban, dabigatran or rivaroxaban) for non-valvular atrial fibrillation at Valenciennes General Hospital (Valenciennes, France) between 1 January, 2016 and 31 December, 2017. We determined compliance with French and European guidelines of DOAC doses as a function of each patient's clinical and laboratory parameters, and thus classified the regime as being appropriately dosed, overdosed or underdosed.

RESULTS

A total of 703 patients (371 taking apixaban, 92 taking dabigatran and 240 taking rivaroxaban) were included in the study. We found that 274 patients (39%) had been prescribed an inappropriate DOAC regime, with underdosing in 241 cases (34%) and overdosing in 33 cases (5%). Underdosing mainly concerned the two most widely prescribed DOACs, i.e. apixaban (39% of all apixaban prescriptions were underdosed) and rivaroxaban (40%). Concomitant treatment with an antidepressant was associated with underdosing of rivaroxaban or apixaban (p = 0.0339). In contrast, initial management in a neurology department was associated with appropriate dosing (p = 0.000146) for both these DOACs.

CONCLUSIONS

Among patients with non-valvular atrial fibrillation aged 80 years and over, about 40% of DOAC prescriptions feature inappropriate dose levels. It might be possible to reduce inappropriate dosing by raising awareness among hospital-based and private-practice prescribers, providing prescription support tools for DOACs, and performing medication reconciliations and reviews at hospital and in private practice.

Determinants for under- and overdosing of direct oral anticoagulants and physicians' implementation of clinical pharmacists' recommendations

AIMS

To analyse the appropriateness of direct oral anticoagulant (DOAC) dosing and determinants for under-and overdosing as well as acceptance and implementation rates of pharmacists' interventions.

METHODS

Cross-sectional study in a tertiary hospital in hospitalized patients with atrial fibrillation on DOACs in 2019 (n = 1688). Primary outcome was the proportion of patients with inappropriate DOAC prescribing with identification of determinants for under-and overdosing. Secondary outcomes included acceptance and implementation rates of pharmacists' recommendations and determination of reasons for nonacceptance/nonimplementation.

RESULTS

Inappropriate prescribing was observed in 16.9% of patients (n = 286) with underdosing (9.7%) being more prevalent than overdosing (6.9%). For all DOACs considered together, body weight<60 kg (odds ratio [OR] 0.46 [0.27-0.77]), edoxaban use (OR 0.42 [0.24-0.74]), undergoing surgery (OR 0.57 [0.37-0.87]) and being DOAC naïve (OR 0.45 [0.29-0.71]) were associated with significantly lower odds of underdosing. Bleeding history (OR 1.86 [1.24-2.80]) and narcotic use (OR 1.67 [1.13-2.46]) were associated with significantly higher odds for underdosing. Determinants with a significantly higher odds of overdosing were renal impairment (OR 11.29 [6.23-20.45]) and body weight<60 kg (OR 2.34 [1.42-3.85]), whereas dabigatran use (OR 0.24 [0.08-0.71]) and apixaban (OR 0.18 [0.10-0.32]) were associated with a significantly lower odds of overdosing compared to rivaroxaban. Physicians accepted the pharmacists' advice in 179 cases (79.2%) consisting of 92 (51.4%) recommendations for underdosing, 82 (45.8%) for overdosing and 5 (2.8%) for contraindications.

CONCLUSION

Inappropriate DOAC prescribing remains common, although there is a slight improvement compared to our study of 2016. Clinical services led by pharmacists help physicians to reduce the number of inadequate prescriptions for high-risk medications such as DOACs.

Direct oral anticoagulant-related medication incidents and pharmacists' interventions in hospital in-patients: evaluation using reason's accident causation theory

Background Direct oral anticoagulants (DOACs) have revolutionised anticoagulant pharmacotherapy. However, DOAC-related medication incidents are known to be common. Objective To assess medication incidents associated with DOACs using an error theory and to analyse pharmacists’ contributions in minimising medication incidents in hospital in-patients. Setting A large University academic hospital in the West Midlands of England. Methods Medication incident data from the incident reporting system (48-months period) and pharmacists’ interventions data from the prescribing system (26-month period) relating to hospital in-patients were extracted. Reason’s Accident Causation Model was used to identify potential causality of the incidents. Pharmacists’ intervention data were thematically analysed. Main outcome measure (a) Frequency, type and potential causality of DOAC-related incidents; (b) nature of pharmacists’ interventions. Results A total of 812 reports were included in the study (124 medication incidents and 688 intervention reports). Missing drug/omission was the most common incident type (26.6%, n = 33) followed by wrong drug (16.1%, n = 20) and wrong dose/strength (11.3%, n = 14). A high majority (89.5%, n = 111) of medication incidents were caused by active failures. Patient discharge without anticoagulation supply and failure to restart DOACs post procedure/scan were commonly recurring themes. Pharmacists’ interventions most frequently related to changes in pharmacological strategy, including drug or dose changes (38.1%, n = 262). Impaired renal function was the most common reason for dose adjustments. Conclusion Prescribers’ active failure rather than system errors (i.e. latent failures) contributed to the majority of DOAC-related incidents. Reinforcement of guideline adherence, prescriber education, harnessing pharmacists’ roles and mandating renal function information in prescriptions are likely to improve patient safety.

Inappropriate dose of nonvitamin-K antagonist oral anticoagulants: prevalence and impact on clinical outcome in patients with nonvalvular atrial fibrillation

BACKGROUND

Limited real-world data are available regarding the outcome of patients treated with inappropriate dose of nonvitamin-K antagonist oral anticoagulants (NOACs).

OBJECTIVE

To assess the prevalence and factors associated with inappropriate dose prescription of NOACs and to evaluate adverse events that come from this inappropriate prescription.

METHODS

Single-center multidisciplinary registry including nonvalvular atrial fibrillation patients treated with NOACs. Based on guidelines criteria for dose reduction, two subcohorts were defined as treated with appropriate or inappropriate NOACs dose. Primary efficacy endpoint was 2-year rate of thromboembolic events. Primary safety endpoint was 2-year rate of major bleeding. Event-free survival curves among groups were compared using Cox-Mantel test.

RESULTS

A total of 760 nonvalvular atrial fibrillation patients were included; 32% patients were treated with dabigatran, 34% with apixaban, 24% with rivaroxaban and 10% with edoxaban. An inappropriate dose was prescribed in 96 patients (12.6%), and in most cases (68%) it was too low. Rivaroxaban (15%) and apixaban (18.5%) were the most frequently prescribed with an inappropriate dose. Patients treated with an inappropriate dose were elderly people, with low-creatinine clearance value, who had experienced previous bleeding and with a high CHADS2 VASc score. In 2 years, a trend for higher numbers of thromboembolic events (5.2 vs. 3.3%, P = 0.348) and less major bleeding (2.1 vs. 4.2%, P = 0.316) has been observed in patients with inappropriate NOACs prescriptions.

CONCLUSION

Nearly 13% of patients were treated with an inappropriate dose of NOACs, in this single-center study. A trend for higher numbers of thromboembolic events was observed in these patients. The results should be considered as hypothesis generating.

Rationale and design of a prospective, multicenter, cross-sectional study of appropriateness evaluation of the prescription of non-vitamin K antagonist oral anticoagulants for Chinese atrial fibrillation patients (Chi-NOACs-AF trial)

BACKGROUND

Non-vitamin K antagonist oral anticoagulants (NOACs) are alternative to vitamin K antagonists (VKAs) for stroke prevention in patients with atrial fibrillation (AF). Along with their widespread clinical use in China, the off-label use of NOACs is commonly seen in real-world practice, which could result in adverse drug events and poor clinical outcomes. However, guideline adherence and label adherence for NOAC prescriptions have not been well evaluated in a real-world setting in China.

METHODS

Between January 2021 and June 2021, a total of 1,750 outpatients or inpatients with AF will be consecutively enrolled at 26 canters in China. Data on patient demographics, clinical characteristics, treatment strategies, and prescribing information related to anticoagulation therapy for patients with AF will be collected. Clinical pharmacists will evaluate the rationality of the anticoagulation regimens and NOAC prescriptions based on the guideline recommendations and drug labels that are approved by the National Medical Products Administration. The primary outcomes will be the prevalence of irrational anticoagulation strategies and the inappropriate NOAC prescriptions, as well as potential risk factors associated with inappropriate prescriptions in patients with AF.

DISCUSSION

This study will be the first national, multicenter, prospective study performed by pharmacists to explore real-world data on the appropriateness of NOAC prescription in Chinese patients with AF.

TRIAL REGISTRATION

The Chi-NOACs-AF trial (Trial number: ChiCTR2000035908).

Inappropriate Dosing of Direct Oral Anticoagulants in Patients with Atrial Fibrillation

Direct Oral Anticoagulants (DOACs) require dose adjustment based on specific patient characteristics, making them prone to incorrect dosing. The current study aimed to evaluate the prevalence of inappropriate DOAC dosing, its predictors, and corresponding outcomes in a single-center cohort of atrial fibrillation (AF) patients. We reviewed all patients with AF treated at Mayo Clinic with a DOAC (Apixaban, Rivaroxaban, or Dabigatran) between 2010 and 2017. Outcomes examined were ischemic stroke /transient ischemic attack (TIA)/embolism and bleeding. 8,576 patients (mean age 69.5 ± 11.9 years, 35.1 % female, CHA₂DS₂-VASc 3.0±1.8) received a DOAC (38.6% apixaban, 35.8% rivaroxaban, 25.6% dabigatran). DOAC dosing was inappropriate in 1,273 (14.8%) with 1071 (12.4%) receiving an inappropriately low dose, and 202(2.4%) an inappropriately high dose. Patients prescribed inappropriate doses were older (72.4 ± 11.7 vs 69.0 ± 11.8, p <0.0001), more likely to be female (43.1% vs 33.7%, p <0.0001), had a higher CHA₂DS₂-VASc score (3.4 ± 1.8 vs 2.9 ± 1.8, p <0.0001) and a greater Charlson co-morbidity index (3.5 ± 3.3 vs 2.9 ± 3.2, p<0.0001). Over 1.2 ±1.6 years (median 0.5 years) follow up; there was no significant difference in the incidence of stroke and/or TIA and/or embolism and bleeding between patients who were inappropriately dosed versus appropriately dosed. In conclusion, DOAC dosing was not in compliance with current recommendations in 15% of AF patients. Patients at higher risk of stroke and/or TIA based on older age, female gender, and higher CHA₂DS₂-VASc score were more likely to be underdosed, but there was no significant difference in outcomes including stroke/TIA/embolism and bleeding.

Relationship between the degree of renal dysfunction and the safety and efficacy outcomes in patients with atrial fibrillation receiving direct oral anticoagulants

BACKGROUND

The clinical evaluation of a direct oral anticoagulant (DOAC) treatment for atrial fibrillation (AF) patients with renal dysfunction has not been sufficiently studied. This study aimed to evaluate the safety and efficacy of DOACs for patients with a severely impaired renal function.

METHODS

This was a retrospective and observational study in a single center. We enrolled 894 consecutive AF patients who were prescribed DOACs, and divided them into three groups based on their creatinine clearance (CrCl) value: CrCl ≥ 50 mL/min group (n = 634), CrCl 30-49 mL/min group (n = 207), and CrCl 15-29 mL/min group (n = 53). We evaluated the occurrence of major bleeding (MB) as the safety outcome and thromboembolic events (TEs) as the efficacy outcome during the follow-up.

RESULTS

The incidence of MB in the CrCl 15-29 mL/min group was significantly higher than in the other groups (CrCl ≥ 50 mL/min group, 0.8/100 person-years; CrCl 30-49 mL/min group, 1.2/100 person-years; CrCl 15-29 mL/min group, 9.0/100 person-years, log rank test, P < .001). On the other hand, there was no significant difference in the incidence of TEs among the three groups. A multivariate analysis using a Cox proportional hazard model adjusted for the age revealed that the CrCl 15-29 mL/min group was significantly associated with increased MB compared to the CrCl ≥ 50 mL/min group (hazard ratio: 9.76, 95% confidence interval: 2.69-35.5, P < .001). Similar results were observed when adjusting for other multiple clinical factors.

CONCLUSION

This study demonstrated that the degree of renal dysfunction was a significant prognostic factor for MB in AF patients receiving DOACs.

Inappropriate direct oral anticoagulant prescriptions in patients with non-valvular atrial fibrillation: cross-sectional analysis of the French CACAO cohort study in primary care

Background

Direct oral anticoagulants (DOACs) account for an increasing proportion of prescriptions in patients with non-valvular atrial fibrillation (NVAF) in primary care. Inappropriate dosing of DOACs is a common problem, with under-dosing being a particular issue. However, conflicting results have been reported about the factors independently associated with inappropriate dosing.

Aim

To describe inappropriate prescriptions of DOACs among patients in the CACAO French nationwide general practice cohort, and to identify the factors independently associated with inappropriate DOAC doses.

Design and setting

Cross-sectional baseline analysis of the CACAO French national multicentre prospective cohort of adult patients in primary care receiving an oral anticoagulant who were recruited between April and October 2014.

Method

A total of 1111 patients from the CACAO cohort who received a DOAC for NVAF were included in this study. Inappropriate prescriptions of DOACs were described (inappropriate dosage, contraindications, non-indications, interactions, and non-compliance with the precautions for use). Multivariate logistic models were used to investigate factors associated with inappropriate DOAC dosing (under-dosing and over-dosing).

Results

Overall, 438 patients (39.4%) received at least one inappropriate DOAC prescription. The most common inappropriate prescription was inappropriate dosage (n = 374, 33.7%), particularly under-dosing (n = 348, 31.3%). Multivariate analysis revealed that factors independently associated with under-dosing were older age, prescription of apixaban or dabigatran, and a CHA2DS2-VASc score ≥2 vs. a score = 1. Factors with over-dosing were kidney failure, a HAS-BLED score ≥3, and older age.

Conclusion

The appropriateness of DOAC prescribing for NVAF can be improved, especially in older patients, and in patients with kidney failure, a higher risk of ischaemic stroke, and/or a higher risk of bleeding. GPs have a key role in increasing the proportion of appropriate DOAC prescriptions via informational, educational, and/or management strategies.

Evaluation of characteristics and dosing regimens in patients with new or recurrent thrombosis on apixaban and rivaroxaban

Direct factor Xa inhibitors, such as apixaban and rivaroxaban, are widely used for treatment and prevention of venous thromboembolism; however, recent cases of therapeutic failure have been reported. Potential risk factors associated with therapeutic failure such as dose deviations outside of package labeling recommendations, and the use of direct factor Xa-specific inhibitor levels to guide clinical decision making continue to be areas of further investigation. Our study aimed to describe characteristics and dosing regimens in patients on apixaban or rivaroxaban who experienced a new or recurrent thrombosis. We performed a retrospective chart review on 190 patients on either apixaban or rivaroxaban presenting to our institution with new or breakthrough thromboembolism. Evaluation of prescribed anticoagulation regimens compared to package labeling recommendations, direct factor Xa inhibitor-specific anti-Xa levels, anticoagulation interruptions, use of parenteral bridge anticoagulation, final anticoagulation regimen disposition, and thrombosis-associated mortality were recorded. In patients presenting with breakthrough thromboembolism, 78% were on a regimen that matched package labeling recommendations. Anti-Xa levels were documented in 66 patients, the majority of which fell within institutional expected ranges at time of thrombosis. Therapy interruptions immediately prior to thrombosis were observed in 22% of patients and 21% of those patients received parenteral anticoagulation during interruption. Upon discharge, 46% of patients continued the same anticoagulation regimen with no changes. The mortality rate was 6%. In patients who present with new thromboembolism on apixaban or rivaroxaban, a thorough review of risks and benefits should be conducted to mitigate future risk of recurrent thrombosis.

Clinical profile of direct oral anticoagulants versus vitamin K anticoagulants in octogenarians with atrial fibrillation: a multicentre propensity score matched real-world cohort study

Atrial fibrillation (AF) is the most common arrhythmia in clinical practice and its prevalence increases with age. Few data are available about the clinical performance of direct oral anticoagulant (DOACs) in patients aged ≥ 80 years with AF. The aim of our propensity score matched cohort study was to compare the safety and efficacy of DOACs versus well-controlled VKA therapy among octogenarians with AF in real life setting. Data for this study were sourced from the multicenter prospectively maintained Atrial Fibrillation Research Database (NCT03760874), which includes all AF patients followed by the participating centers, through outpatient visits every 3 to 6 months. The database was queried for AF patients aged ≥ 80 years who received DOACs or VKAs treatment. The primary effectiveness endpoint was the occurrence of thromboembolic events (a composite of stroke, transient ischemic attack, systemic embolism); the primary safety endpoint was the occurrence of major bleeding; the secondary endpoint was all-cause mortality. The database query identified 774 AF patients aged ≥ 80 years treated with VKAs and 279 with DOACs. Propensity score (2:1) matching selected 252 DOAC and 504 VKA recipients. The mean follow-up was 31.07 ± 14.09 months. The incidence rate of thromboembolic events was 13.79 per 1000 person-years [14.80 in DOAC vs 13.34 in VKA group, Hazard Ratio 1.10; 95% confidence interval (CI) 0.49 to 2.45; P = 0.823]. The incidence rate of intracranial hemorrhage (ICH) was 8.06 per 1000 person-years (3.25 in DOAC vs 10.23 in VKA group, HR 0.33; 95% CI 0.07 to 1.45; P = 0.600). Through these incidence rates, we found a positive net clinical benefit (NCB) of DOACs over VKAs, equal to + 9.01. The incidence rate of all-cause mortality was 105.05 per 1000 person-years (74.67 in DOAC vs 118.67 in VKA group, Hazard Ratio 0.65; 95% CI 0.47 to 0.90; P = 0.010). The concomitant use of antiinflammatory drugs (HR 7.90; P < 0.001) were found to be independent predictor of major bleeding. Moreover, age (HR 1.17; P < 0.002) and chronic kidney disease (HR 0.34; P = 0.019) were found to be independently associated with thromboembolic events. In our study no significant difference in terms of both thromboembolic and major bleeding events, but a significant lower incidence of all-cause mortality, was detected in AF patients aged ≥ 80 years treated with DOACs vs VKAs.

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.

The role of clinical pharmacy anticoagulation services in direct oral anticoagulant monitoring

The role of dedicated anticoagulation management services (AMS) for patients receiving direct oral anticoagulant (DOAC) therapy is unclear. The objective of our study was to describe DOAC management in patients who were and were not managed by an AMS. We conducted a retrospective cohort study among patients with atrial fibrillation at the University of Utah Health (UUH) who received DOAC therapy between January 2013 and June 2016. Patients in the AMS group were managed by a pharmacist-led AMS whereas those in the non-AMS group were managed by other providers. The number and type of provider encounters and interventions related to DOAC therapy and a composite endpoint of thromboembolism, bleeding, and all-cause mortality were recorded. Overall, 90 and 370 patients were managed in the AMS and non-AMS groups, respectively. AMS group patients had greater chronic disease burden as measured by the Charlson comorbidity index. AMS group patients had more frequent DOAC-related encounters than non-AMS group patients but both groups had similar DOAC therapy intervention rates. Over half of patients in the AMS group received potentially duplicative interventions from their regular clinicians. The composite endpoint occurred in 18.9% and 13.5% of AMS and non-AMS group patients, respectively (p = 0.29). Patients managed by AMS providers were more complex and had more frequent encounters regarding their DOAC therapy than those managed by non-AMS providers. However, there was evidence of duplicative DOAC therapy management efforts. No difference between AMS and non-AMS groups in the composite clinical endpoint was detected.

Creatinine monitoring patterns in the setting of direct oral anticoagulant therapy for non-valvular atrial fibrillation

Guidelines and experts note that patients with atrial fibrillation require regular renal function monitoring to ensure safe use of direct oral anticoagulants (DOACs). Insufficient monitoring could lead to inappropriate dosing and adverse events. Our objective was to describe the frequency of insufficient creatinine monitoring among patients on DOACs, and to describe clinical factors associated with insufficient monitoring. We hypothesized that renal impairment would be associated with insufficient monitoring. A retrospective cohort study was performed with data from the Michigan Anticoagulant Quality Improvement Initiative. Patients were included if they initiated DOAC therapy for stroke prevention related to atrial fibrillation, remained on therapy for ≥ 1 year, and had baseline creatinine and weight measurements. Creatinine clearance (CrCl) was calculated via Cockcroft-Gault equation. Our outcome was the presence of insufficient creatinine monitoring, defined as: < 1 creatinine level/year for patients with CrCl > 50, or < 2 creatinine levels/year for patients with CrCl ≤ 50. Multivariable analysis was done via logistic regression. Study population included 511 patients. In overall, 14.0% of patients received insufficient monitoring. Among patients with CrCl > 50, 11.5% had < 1 creatinine level/year. Among patients with CrCl ≤ 50, 27.1% received < 2 creatinine levels/year. Baseline renal dysfunction was associated with a higher likelihood of insufficient creatinine monitoring (adjusted odds ratio 3.64, 95% confidence interval 1.81-7.29). This shows a significant gap in the monitoring of patients on DOACs-patients with renal impairment are already at higher risk for adverse events. Future studies are needed to describe the barriers in monitoring these patients and to identify how to optimally address them.

Burden of Inappropriate Prescription of Direct Oral Anticoagulants at Hospital Admission and Discharge in the Elderly: A Prospective Observational Multicenter Study

INTRODUCTION

Direct oral anticoagulants (DOACs) were developed to overcome some of the limitations associated with vitamin K antagonists (VKAs), such as interindividual variability or the need for therapeutic drug monitoring. However, the complexity of DOAC dose regimens can still lead to dosing errors and potential bleeding-related or thromboembolic adverse events, especially in the elderly.

OBJECTIVE

Our objective was to evaluate the rate of inappropriate preadmission DOAC prescriptions at hospital and to evaluate the ability of hospitals to correct them.

METHODS

An observational prospective study was conducted in elderly patients (aged ≥ 65 years) hospitalized in six acute units of three Parisian university hospitals between February and July 2018. DOAC prescriptions prior to admission and at discharge were analyzed according to the guidelines in the summaries of product characteristics.

RESULTS

A total of 157 patients were included in the study, with a median age of 84 years (interquartile range [IQR] 77-89). The median glomerular filtration rate, determined with the Cockcroft-Gault equation, was 48 mL/min (IQR 35-61). Apixaban was the most frequently prescribed drug, mainly for atrial fibrillation. Overall, 48 (30.6%) and 34 (22.4%) prescriptions were inappropriate prior to admission and at discharge, respectively, showing a significant decrease (p < 0.001). Hospitals significantly corrected more inappropriate prescriptions (37.5%) than they generated (4.6%) (p < 0.05). The nature of the inappropriate prescribing was underdosing (68.8% and 76.5% prior to admission and at discharge, respectively), followed by overdosing (stable rate at almost 20%) and indication errors. No risk factors for inappropriate use were identified by our analysis.

CONCLUSION

One-third of DOAC preadmission prescriptions for elderly patients were inappropriate, indicating that a need remains to strengthen DOAC prescribing guidelines in ambulatory clinical practice. However, the rate of inappropriate prescriptions decreased at patient discharge. Future studies are needed to test actions to promote the proper use of DOACs.

Evaluation of oral anticoagulants in atrial fibrillation patients over 80 years of age with nonsevere frailty

BACKGROUND

The safety and efficacy of an oral anticoagulant (OAC) treatment and the difference between direct OACs (DOACs) and warfarin in nonsevere frail elderly patients with AF are unclear.

METHODS

This was a retrospective and observational study of 354 patients over 80 years of age with nonsevere frailty who were diagnosed with AF and treated with OACs. Nonsevere frailty was defined as a clinical frailty scale score of <7. Bleeding and thromboembolic events during the OAC treatment were followed up.

RESULTS

Of 354 patients enrolled, 273 (77.1%) received DOACs and 81 (22.9%) received warfarin. Of 273 patients receiving DOACs, there were 210 (76.9%) prescribed with appropriate doses of DOACs. Of 81 warfarin-treated patients, 53 (65.4%) were prescribed an appropriate dose of warfarin. During a follow-up of 33.1 (14.0-51.0) months, 15 patients (1.5/100 person-years) had bleeding events and 10 (1.0/100 person-years) had thromboembolic events while on an OAC treatment. The incidence ratio of bleeding events in patients receiving DOACs was lower than that in those receiving warfarin (1.0/100 person-years vs 2.9/100 person-years, hazard ratio [HR]: 0.26, 95% confidence interval [CI]: 0.07-0.91, P = .036). There was no significant difference in the incidence of thromboembolic events between the DOAC and warfarin treatment groups (0.88/100 person-years vs 1.4/100 person-years, HR: 0.63, 95% CI: 0.16-2.57, P = .52).

CONCLUSIONS

OACs are substantially safe and effective for preventing thromboembolic events in nonsevere frail patients over 80 years of age. Particularly, DOACs can be used more safely than warfarin.

Use of rivaroxaban in patients attending a hematology unit in clinical practice

Aim: To determine drug persistence and rates of events among patients treated with rivaroxaban in a hematology unit. Methods: Retrospective study of patients that started treatment with rivaroxaban, in the hematology unit of a tertiary hospital. Results: A total of 161 patients were included, of whom 83.9% had atrial fibrillation and 11.2% venous thromboembolism, and 76.4% of patients were taking rivaroxaban 20 mg, 22.4% 15 mg and 1.2% 10 mg. After a follow-up of 1.8 ± 1.1 years, only four patients (2.5%) discontinued treatment. Rates of thromboembolic events, major bleeding/clinically relevant nonmajor bleeding and intracranial hemorrhage were 1.1, 2.8, 0.3 events per 100 patient-years, respectively. Conclusion: In patients attended in a hematology unit, medication persistence was high, and the incidence of outcomes low.

Inappropriate non-vitamin K antagonist oral anticoagulants prescriptions: be cautious with dose reductions

BACKGROUND

Non-vitamin K antagonist oral anticoagulants (NOACs) are prescribed to patients with atrial fibrillation (AF) to reduce the risk of stroke. Prescribing the correct dose warrants careful consideration of 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 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 NOAC dose.

METHODS

Our goal was to determine the appropriateness of all prescriptions, as compared with the product labelling approved by the European Medicines Agency, to address common pitfalls in prescribing NOACs. AF patients with a first NOAC prescription between January 2012 and December 2016 were identified from our electronic hospital information system (Martini Hospital, Groningen, the Netherlands).

RESULTS

The study included 3,231 AF patients who had started on an NOAC; 10.7% received an inappropriate dose and the appropriateness of the prescription could not be determined in 14.1%. Underdosing and overdosing occurred in 5.4% and 4.5% of all prescriptions, respectively. A reduced-dose NOAC was a predictor for incorrect prescribing (odds ratio: 2.70, 95% confidence interval: 2.13-3.41). Patient factors were identified that predicted incorrect prescriptions for dabigatran and apixaban.

CONCLUSION

An incorrect prescription occurred more often in the reduced-dose NOAC group. Clinical parameters such as renal function are often unknown whilst these are essential to determine the right NOAC and dose.

The treatment pattern and adherence to direct oral anticoagulants in patients with atrial fibrillation aged over 65

Objective

In this study, we aimed to assess the utilization pattern (potentially inappropriate dosing and concomitant use of contraindicated drugs) and adherence to direct oral anticoagulants (DOACs), including apixaban, dabigatran, and rivaroxaban, in patients with atrial fibrillation (AF) unsuitable for warfarin.

Methods

We used nationally representative data, namely Health Insurance Review and Assessment Service-Aged Patient Sample 2014, that included medical and pharmacy claims of approximately 1 million patients aged 65 or older. We included patients who had at least one diagnosis of AF and at least one prescription of DOAC between January 1 and December 31, 2014. In 2014, DOACs were reimbursed only to patients with AF unsuitable for warfarin. Appropriate dosing and contraindicated drugs were determined according to the Summary of Product Characteristics for each DOAC. Multivariate logistic regression was performed to examine the factors contributing to the concomitant use of contraindicated drugs. To assess adherence, we calculated the medication possession ratio (MPR).

Results

The percentage of inappropriate dosing was 11.8% among 1,234 patients with AF; it was the highest in rivaroxaban users (16.8%). Contraindicated drugs were prescribed to 236 patients (19.1%). Clinics, smaller healthcare institutions, and outpatient visits were significantly related to contraindicated drug use. The mean MPRs were 0.95, 0.93, and 0.91 for apixaban, dabigatran, and rivaroxaban, respectively (P = 0.075).

Conclusions

Careful monitoring is warranted in patients with AF aged over 65 who were unsuitable for warfarin to reduce the incidence of inappropriate dosing and concomitant use of contraindicated drugs.

Direct oral anticoagulants: a review of common medication errors

Stroke and venous thromboembolism continues to be a major cause of morbidity and mortality worldwide. The use of anticoagulation therapy has proven effective in the prevention of stroke and management of thromboembolism; however, initiating treatment may bear clinical burden given the capacity of these agents to cause bleeding. Originally, warfarin has been primarily used, but with the approval of direct oral anticoagulants, therapeutic recommendations have shifted to direct oral anticoagulants for first line therapy for venous thromboembolism for patients without cancer. As compared to warfarin, direct oral anticoagulants are associated with predictable pharmacokinetic profiles, lower bleeding risks, and minimal drug interactions. Complexities in the medication use process can however heighten the risks of causing adverse events. The purpose of this article is to describe common medication errors associated with direct oral anticoagulants, provide practical guidance on the management of direct oral anticoagulants, and suggest strategies to reduce errors. Efforts to minimize medication errors involve the participation of an interdisciplinary team that has standardized policies, risk reduction strategies, and guiding principles to achieve optimal therapeutic outcomes. Current primary literature is not robust in assessment of clinical impact of medication errors associated with DOACs but reports of adverse drug events have been noted. Future studies should be guided to assess clinical outcomes associated with medication errors and identify potential clinical interventions to optimize therapy.

Real-world study of direct oral anticoagulant dosing patterns in patients with atrial fibrillation

BACKGROUND

Direct oral anticoagulants (DOACs) are preferred for stroke prevention in atrial fibrillation (AF). However, off-label doses have been associated with increased risk of adverse events.

OBJECTIVE

The objective of this study was to compare the frequency and outcomes of labeled versus off-label DOAC dosing in patients with AF.

METHODS

This retrospective cohort study included adults diagnosed with nonvalvular AF (NVAF), discharged from University of Utah Health on DOAC therapy between 7/1/2017 and 9/30/2017. The primary outcome was off-label DOAC dosing frequency, defined as dosing inconsistent with manufacturer labeling. Secondary outcomes included variables associated with off-label dosing and a composite of adverse events (major bleeding, thromboembolism, and all-cause mortality) in the 90 days following the index hospital discharge.

RESULTS

Of 249 included patients, 16.1% were discharged with off-label dosing. Factors associated with off-label dosing included advanced age, lower body mass index, decreased renal function, use of rivaroxaban, and hepatic impairment. The majority of off-label patients (70%) received lower-than-recommended DOAC dosing. Prescriber rationale for off-label prescribing was documented in 25% of patients and included anti-Xa guided dosing, high risk for bleeding or thromboembolism, and prior history of on-therapy adverse events. The rate of adverse events between labeled and off-label DOAC doses was not statistically different (10.0% vs. 6.7%, p=0.299), although this is likely due to small sample size.

CONCLUSIONS

Off-label DOAC prescribing for stroke prevention in NVAF at University of Utah Health was consistent or lower than previously published studies. Off-label dosing most often involved under-dosing of rivaroxaban. Future research should investigate the role of provider rationale and insight in optimizing DOAC therapy outcomes.

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

Background and Objectives: Appropriate dosing of direct oral anticoagulants (DOACs) is required to avoid under- and overdosing that may precipitate strokes or thromboembolic events and bleedings, respectively. Our objective was to analyze the appropriateness of DOAC dosing according to the summaries of product characteristics (SmPC). Furthermore, determinants for inappropriate prescribing were investigated. Methodology: Retrospective cohort study of hospitalized patients aged ≥60 years with at least one DOAC intake during hospital stay. Descriptive analyses were used to summarize the characteristics of the study population. Chi-square test was used to evaluate differences between DOACs. Binary logistic regression analysis was performed to assess determinants for inappropriate prescribing. Results: For the 772 included patients, inappropriate dosing occurred in 25.0% of hospitalizations with 23.4, 21.9, and 29.7% for dabigatran, rivaroxaban, and apixaban, respectively (p = 0.084). Underdosing was most prevalent for apixaban (24.5%) compared to dabigatran (14.0%) and rivaroxaban (12.8%), p < 0.001. In 67.1% (apixaban), 26.7% (dabigatran), and 51.2% (rivaroxaban) of underdosed DOAC cases according to the SmPC, the dose would be considered appropriate according to the European Heart Rhytm Association (EHRA) guidelines. Overdosing was observed in 4.5% (apixaban), 4.7% (dabigatran), and 7.7% (rivaroxaban) of patients. For all DOACs, our analysis showed an age ≥80 years (p = 0.036), use of apixaban (p = 0.026), DOAC use before hospitalization (p = 0.001), intermediate renal function (p = 0.014), and use of narcotic analgesics (p = 0.019) to be associated with a higher rate of inappropriate prescribing. Undergoing surgery was associated with a lower odds of inappropriate prescribing (p = 0.012). For rivaroxaban, use of medication for hypothyroidism (p = 0.027) and the reduced dose (p < 0.001) were determinants for inappropriate prescribing. Treatment of venous thromboembolism was associated with less errors (p = 0.002). For apixaban, severe renal insufficiency (p < 0.001) and initiation in hospital (p = 0.016) were associated with less and the reduced dose (p < 0.001) with more inappropriate prescribing. No determinants were found in the dabigatran subgroup. Conclusions: Inappropriate DOAC prescribing is frequent with underdosing being the most common drug related problem when using the SmPC as reference. More appropriate prescriptions were found when taking the EHRA guidelines into account. Analysis of determinants of inappropriate prescribing yielded insights in the risk factors associated with inappropriate DOAC prescriptions.

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

AIMS

Although oral anticoagulants (OACs) are effective in preventing stroke in older people with atrial fibrillation (AF), they are often underused in this particularly high-risk population. The aim of the present study was to assess the appropriateness of OAC prescription and its associated factors in hospitalized patients aged 65 years or older.

METHODS

Data were obtained from the retrospective phase of Simulation-based Technologies to Improve the Appropriate Use of Oral Anticoagulants in Hospitalized Elderly Patients With Atrial Fibrillation (SIM-AF) study, held in 32 Italian internal medicine and geriatric wards. The appropriateness of OAC prescription was assessed, grouping patients in those who were and were not prescribed OACs at hospital discharge. Multivariable logistic regression was used to establish factors independently associated with the appropriateness of OAC prescription.

RESULTS

A total of 328 patients were included in the retrospective phase of the study. Of these, almost 44% (N = 143) were inappropriately prescribed OACs, being mainly underprescribed or prescribed an inappropriate antithrombotic drug (N = 88). Among the patients prescribed OACs (N = 221), errors in the prescribed doses were the most frequent cause of inappropriate use (N = 55). Factors associated with a higher degree of patient frailty were inversely associated with the appropriateness of OAC prescription.

CONCLUSIONS

In hospitalized older patients with AF, there is still a high prevalence of inappropriate OAC prescribing. Characteristics usually related to frailty are associated with the inappropriate prescribing. These findings point to the need for targeted interventions designed for internists and geriatricians, aimed at improving the appropriate prescribing of OACs in this complex and high-risk population.

Anticoagulation with rivaroxaban in a hematology unit: clinical profile, events and discontinuation rates in real-life patients with nonvalvular atrial fibrillation

AIM

To assess the clinical profile and thromboembolic and bleeding events in patients with nonvalvular atrial fibrillation (AF) who were attended in a hematology unit.

METHODS

Retrospective study of AF patients that started treatment with rivaroxaban between February 2012 and June 2016 in a hematology unit from a tertiary hospital in Spain.

RESULTS

Overall, 243 patients (mean age 78.4 ± 10.1 years; 47.5% women, CHA₂DS₂-VASc 3.7 ± 1.5) were included. After a mean follow-up of 16.5 ± 12.7 months, rivaroxaban was discontinued in only 2.4% of patients. During the follow-up, seven (2.0 events/100 patient-years) patients had a thromboembolic event and six patients (1.7 events/100 patient-years) a major bleeding.

CONCLUSION

Rivaroxaban was effective and safe among AF patients treated in a hematology unit, with very low discontinuation rates.

Patient Education on Oral Anticoagulation

Given the potential harm associated with anticoagulant use, patient education is often provided as a standard of care and emphasized across healthcare settings. Effective anticoagulation education involves face-to-face interaction with a trained professional who ensures that the patient understands the risks involved, the precautions that should be taken, and the need for regular monitoring. The teaching should be tailored to each patient, accompanied with written resources and utilize the teach-back method. It can be incorporated in a variety of pharmacy practice settings, including in ambulatory care clinics, hospitals, and community pharmacies.

How I treat recurrent venous thromboembolism in patients receiving anticoagulant therapy

Oral anticoagulant therapy for venous thromboembolism is very effective. When oral anticoagulants are managed well, the risk of recurrence is approximately 2 per 100 patient-years. The main reasons for a breakthrough event are underlying disease and subtherapeutic drug levels. The most common underlying disease that results in recurrence on treatment is cancer. Subtherapeutic drug levels can be caused by poor adherence to the drug regimen, interactions with other drugs or food, or inappropriate dosing. It is important to investigate and understand the cause whenever such an event occurs and to improve management of anticoagulants thereby avoiding further recurrences. Here we present 4 illustrative cases together with a discussion of the underlying pathology. Whereas the mechanisms are usually quite well understood, the management of further anticoagulation after a breakthrough event is based on minimal or no clinical trial evidence.