New oral anticoagulants: their advantages and disadvantages compared with vitamin K antagonists in the prevention and treatment of patients with thromboembolic events

Evaluation of oral factor Xa inhibitor-associated extracranial bleeding reversal with andexanet alfa

INTRODUCTION

A reversal agent for factor Xa (FXa) inhibitors, andexanet alfa, was Food and Drug Administration approved without extensive study of clinical effectiveness, due to an overwhelming demand for FXa inhibitor reversal. In this study, we aimed to describe patient selection, clinical effectiveness, and safety of FXa inhibitor reversal with andexanet alfa in patients presenting with extracranial bleeding.

METHODS

Consecutive patients who received andexanet alfa for reversal of FXa inhibitor-associated extracranial hemorrhage were identified. The primary outcome of interest was hemostatic efficacy, assessed using the Sarode et al criteria. Secondary outcomes of interest included incidence of thrombotic episodes post-reversal until discharge and in-hospital mortality.

RESULTS

Twenty-one patients met the inclusion criteria (61.9% male, mean age: 73 years). Anticoagulation reversal with andexanet alfa was deemed effective (excellent [n = 3], good [n = 7]) in 10 (47.6%) patients, and poor in 11 patients (52.4%). Eight (38.1%) patients died, of which three were surgically managed, with all causes of death attributed to hemorrhage. Six ischemic complications occurred in four patients (19.0%); ischemic stroke (n = 2], pulmonary embolism (n = 1), deep vein thrombosis (n = 1), liver ischemia (n = 1), and bowel ischemia (n = 1).

CONCLUSION

We report poor overall outcomes, a low rate of hemostatic effectiveness, and a high rate of ischemic complications and mortality in this retrospective analysis of oral FXa inhibitor reversal with andexanet alfa for extracranial bleeds. More rigorous epidemiological, and ideally randomized studies, are needed to determine the role of andexanet alfa for FXa inhibitor-associated bleeding for extracranial hemorrhages, where large variation in severity and presentation exists.

Effectiveness of multimedia interventions in the provision of patient education on anticoagulation therapy: A review

OBJECTIVE

A literature review was conducted to identify available evidence on the use of multimedia patient educational interventions on anticoagulation therapy.

METHODS

A literature search was conducted on 9/4/2020 via six research databases. Publications that evaluated the effects of these interventions on anticoagulation therapy were included.

RESULTS

The review included ten original research studies (five randomized controlled trials, four observational studies and a pre- and post-interventional study), a systematic review and meta-analysis, three systematic reviews, a scoping review, and a literature review. Multimedia interventions significantly improved knowledge after education, but no significant differences found when compared to traditional methods. There was insufficient evidence to conclude whether knowledge retained over time. Patients were equally satisfied with both methods. Multimedia interventions significantly reduced healthcare professional's time required for education. Heterogeneity in intervention, methodology and results limited comparison and combination of findings across studies.

CONCLUSION

Multimedia patient educational interventions on anticoagulation therapy have similar outcomes to traditional methods in knowledge improvement and satisfaction, but they save health personnel time.

PRACTICE IMPLICATIONS

There is lack of evidence to support the effectiveness of multimedia interventions in educating patients on anticoagulation therapy. Larger randomized studies evaluating their benefits in health outcomes and clinical practice are warranted.

Drug-drug interactions with direct oral anticoagulants associated with adverse events in the real world: A systematic review

BACKGROUND

Direct oral anticoagulants (DOACs) have emerged as safe and effective alternatives to Vitamin-K antagonists for treatment and prevention of arterial and venous thrombosis. Due to their novelty, pharmacokinetic DOAC drug-drug interactions (DDIs) that result in clinical adverse events have not been well-documented.

OBJECTIVE

This study aims to systematically review reported pharmacokinetic DDIs resulting in clinical adverse events through documented observational evidence to better inform clinicians in clinical practice.

METHODS

A comprehensive literature review of EMBASE, MEDLINE, and Ovid HealthStar was conducted through March 10th, 2020. Two independent reviewers screened and extracted data from eligible articles according to pre-established inclusion and exclusion criteria. Articles reporting bleeding or thrombotic outcomes in non-controlled (observational) settings resulting from suggested pharmacokinetic DOAC DDIs were included.

RESULTS

A total of 5567 citations were reviewed, of which 24 were included following data extraction. The majority were case reports (n = 21) documenting a single adverse event resulting from a suspected DOAC DDI, while the remaining papers were a case series (n = 1) and cohort studies (n = 2). The most commonly reported interacting drugs were amiodarone and ritonavir (bleeding), and phenobarbital, phenytoin, and carbamazepine (thrombosis). Bleeding events more often resulted from a combined mechanism (P-glycoprotein AND CYP3A4 inhibition), whereas thrombotic events resulted from either combined OR single P-glycoprotein/CYP3A4 induction.

CONCLUSION

Current literature evaluating the real-world risk of DOAC DDIs is limited to few case reports and retrospective observational analyses. Clinicians are encouraged to continue to report suspected drug interactions resulting in adverse events.

Direct-acting oral anti-coagulants in dental practice: A Retrospective Observational Study (Part 1)

OBJECTIVES

The objective of this retrospective observational study was to determine the incidence of direct-acting oral anti-coagulant (DOA) use in patients receiving invasive dental procedures. The secondary objective was to investigate the precautionary measures implemented and the post/intraoperative complications associated with DOA use.

METHODS

Electronic record database, Axium, was retrospectively reviewed, and patients using NGOA and treated between 2010 and 2017 were identified. Charts of patients who underwent invasive dental procedures were further reviewed to investigate the preoperative/intraoperative precautionary measures taken and identify any intraoperative/postoperative complications.

RESULTS

A total of 130 patients were identified, with their annual number steadily rising from 12 in 2011 to 52 in 2016. Among those, 64 patients (49.23%) underwent invasive dental procedures. Pretreatment medical consults were obtained in all patients undergoing invasive procedures; however, only 7 (10.94%) were instructed to discontinue their DOA. Preoperative laboratory testing was obtained for two patients. Intraoperatively, 34 (53.13%) cases of excessive bleeding were reported, all were locally controlled with hemostatic agents. Only 4 instances of postoperative complications were documented.

CONCLUSIONS

Despite the rise in the use of DOA, there is no consistent pattern for preoperative laboratory testing and DOA discontinuations. Expert consensus may be of great importance to develop practice guidelines.

New oral anticoagulants - possible extension to other indications (Review)

Anticoagulant treatment is necessary in various conditions, with curative or preventive purposes. Until recently, the only oral anticoagulants available have been vitamin K antagonists. To overcome the disadvantages of the antivitamin K oral anticoagulants, new oral anticoagulants (NOACs) have been developed and included in clinical trials. After more than 60 years of using vitamin K antagonists, the introduction of NOACs represent a medical breakthrough, with promising prospects. Due to their promising results and better safety profile, NOACs have become an appealing alternative to vitamin K antagonists in a short period of time. NOACs have been approved for the prevention and treatment of venous thromboembolism and for the prevention of stroke in patients with nonvalvular atrial fibrillation. Starting with postoperative venous thromboprophylaxis after hip replacement surgery, NOACs have been approved also for other clinical situations. Rivaroxaban is the first oral anticoagulant approved to be used in combination with an antiplatelet agent to prevent atherothrombotic events in adults with coronary artery disease and/or peripheral artery disease. However, further investigation is needed to establish which group of patients would benefit most from this medical approach. Furthermore, preliminary studies have shown that NOACs seem to be a reasonable choice of anticoagulation for patients with cancer, but further studies are expected.

Use of the VENOVO™ and Sinus Obliquus™ venous stents in the treatment of non-thrombotic or post-thrombotic iliac vein lesions - Short-term results from a multi-centre Asian cohort

OBJECTIVES

Deep venous stenting with intravascular ultrasound (IVUS) guidance is gaining favour as the treatment modality of choice for symptomatic ilio-femoral venous occlusive disease. The aim was to determine the short-term patency and symptomatic relief gained using the Bard Venovo™ and Optimed Sinus Obliquus™ stents in the endovascular treatment of non-thrombotic iliac vein lesions (NIVL) and post-thrombotic venous obstruction (PTO) from two Asian tertiary vascular centres.

METHODS

Sixty patients (males = 21/60 (35.0%); median age 67 years (interquartile range 54-77)) who underwent IVUS interrogation and ilio-femoral stenting (June 2018-May 2019) in two Asian centres were prospectively followed. Clinical improvement was determined by the revised Venous Clinical Severity Score (rVCSS), pain using the Visual Analogue Scale (VAS) and ulcer healing rate. Patency rates were evaluated using Duplex ultrasound and computer tomography venogram.

RESULTS

Seventy-one legs were interrogated and stented; 11/60 (18.3%) patients had a bilateral procedure. Indications for surgery were PTO (n = 11/71 (15.5%)) and NIVL (n = 60/71 (84.5%)). Twenty-seven of 71 (38.0%) patients had CEAP 6 disease. The median follow-up was 283 (interquartile range 211-370) days. Technical and procedural success was both 100%. Twenty-one of 71 (29.6%) legs had a combination of Venovo™ and Sinus Obliquus™ stents inserted for concurrent ilio-caval and iliac lesions. There were no major post-operative complications. Six-month primary, assisted primary and secondary patency rates were 94.1, 97.1 and 100%, respectively. There were no stent fractures. Mean rVCSS and VAS improved from 12.26 (±3.31) to 4.33 (±2.78) and 6.97 (±1.38) to 2.03 (±1.65), respectively, at three months (p < 0.01). Complete ulcer healing was seen in 27/27 (100%) patients at three months.

CONCLUSION

Use of Venovo™ and Sinus Obliquus™ stents for symptomatic ilio-femoral venous disease showed excellent six-month primary patency rate with no stent fractures. There were significant clinical improvement and low-device-related complications. Longer follow-up is awaited to see how these dedicated venous stents perform.

Management of Outpatient Warfarin Therapy amid COVID-19 Pandemic: A Practical Guide

Many healthcare resources have been and continue to be allocated to the management of patients with COVID-19. Therefore, the ongoing care of patients receiving oral anticoagulation with warfarin is likely to be compromised amid this unprecedented crisis. This article discusses a stepwise algorithm for the management of outpatient warfarin therapy. Alternative management strategies are presented and discussed, including alternative pharmacological therapy options and self-monitoring. Our algorithm aims to help clinicians safely optimize the treatment of patients requiring anticoagulation therapy in the context of the global response to the current pandemic.

Management of Outpatient Warfarin Therapy amid COVID-19 Pandemic: A Practical Guide

Many healthcare resources have been and continue to be allocated to the management of patients with COVID-19. Therefore, the ongoing care of patients receiving oral anticoagulation with warfarin is likely to be compromised amid this unprecedented crisis. This article discusses a stepwise algorithm for the management of outpatient warfarin therapy. Alternative management strategies are presented and discussed, including alternative pharmacological therapy options and self-monitoring. Our algorithm aims to help clinicians safely optimize the treatment of patients requiring anticoagulation therapy in the context of the global response to the current pandemic.

Epidemiology and treatment of atrial fibrillation in patients with type 2 diabetes in the UK, 2001-2016

Patients with Type 2 diabetes mellitus (T2DM) have an increased risk of atrial fibrillation (AF). The current study aimed to investigate the prevalence and treatment of AF in patients with T2DM, assess the impact of direct oral anticoagulants (DOACs) introduction on oral anticoagulant (OACs) prescribing rates, and factors associated with OAC initiations in patients with T2DM and AF. The Health Improvement Network (THIN) database (2001-2016), was used to examine the annual prevalence and treatment of AF in T2DM. The impact of DOACs introduction on OAC prescribing rates were investigated using interrupted time series analysis (ITS). Factors associated with OAC initiations were also identified using multivariate logistic regression. The prevalence of AF increased from 2.7 [95% confidence intervals (CI) 2.5-2.8] in 2001 to 5.0 (4.9-5.1) in 2016 per 100 persons. OACs prescribing within 30-days of AF diagnosis increased from 21.5% in 2001 to 56.8% in 2016. ITS analysis showed that OAC prescribing increased after DOAC introduction (P < 0.001), however, no immediate change was observed (P = 0.29). T2DM patients with AF, aged 60-79, male gender and BMI ≥ 25 were more likely to receive OAC, adjusted OR 1.3 (1.2-1.5) for aged 60-79, 1.3 (1.2-1.4) for male gender and 2.0 (1.9-2.2) for BMI ≥ 25, respectively. This study highlighted an increase in prevalence of AF in patients with T2DM during the study period. Further studies are warranted to investigate factors contributing to the underuse of OAC in patients with T2DM and AF.

Effect of a novel pharmacist-led reporting system on appropriate use of direct-acting oral anticoagulants (DOACs) in a patient-centered medical home

Recent analyses demonstrate roughly 16-24% of patients taking direct-acting oral anticoagulants (DOACs) are prescribed an inappropriate dose, exposing patients to increased risk of thrombosis or bleeding. The use of reporting systems in the outpatient setting can efficiently identify potential medication errors and safety concerns. The purpose of this study was to evaluate the effect of a novel pharmacist-driven reporting system on appropriate prescribing of DOACs in the outpatient setting. This single-center qualitative study was conducted within a patient-centered medical home (PCMH). Reports were generated monthly to include all new DOAC prescriptions. Branching logic and filters were utilized within a secure web application to make the reporting process more efficient and identify regimens needing an intervention. Pharmacists reviewed the regimens populated by filters and made recommendations to prescribers as appropriate. The number of interventions proposed was captured as the primary outcome. Secondary outcomes include the nature of drug therapy problems identified and number of interventions accepted by prescribers. A total of 107 patients were analyzed for appropriateness from November 2017 to February 2019. Of the regimens included for review, 15 regimens were identified as potentially inappropriate. The nature of drug therapy problems identified include under dosing (4.25%), overdosing (2.13%), correction of documentation (2.13%), clarification of indication (3.19%), and ordering laboratory studies (3.19%). Of the interventions recommended, fourteen (93%) were accepted. Pharmacists integrated in a PCMH are well positioned to monitor and resolve DOAC drug therapy problems using local clinical reports.

Mortality in relation to presence and type of oral antithrombotic agent among adult trauma patients: a single-center retrospective cohort study

PURPOSE

Oral anticoagulants (AC) and antiplatelet (AP) agents are increasingly prescribed to prevent and treat acute and chronic thrombotic conditions. The direct oral anticoagulants (DOAC), a newer class of AC, raise concerns in the trauma setting. Our study aims to compare the mortality rates and other outcomes among adult trauma patients based on pre-admission AC/AP status.

METHODS

We conducted a retrospective cohort study of a prospectively collected database of trauma patients previously on DOAC, warfarin, aspirin or clopidogrel. A matched control group of trauma patients not receiving AC/AP was used for comparison. Our primary endpoint was in-hospital mortality according to antithrombotic medication class. Secondary endpoints included length of stay (LOS), intensive care unit (ICU) admission, need for blood transfusion, and discharge to a dependent setting. Univariate and multivariate analyses were conducted.

RESULTS

There were 996 exposed patients and 234 controls, with no major clinically significant difference among study groups in terms of gender, injury site, injury severity, mechanism, and comorbidities. The mortality rates were 2.14% (control, 5/234), 2.88% (DOAC, 3/104), 3.34% (aspirin, 17/509), 7.63% (warfarin, 18/236), 9% (clopidogrel, 8/89), and 13.79% (aspirin + clopidogrel, 8/58) (p < 0.001). In multivariate analyses, there was no difference regarding mortality between DOAC and reference groups. Blood transfusion was more likely in patients receiving warfarin or AP than those prescribed DOAC.

CONCLUSION

There was no evidence of increased mortality or blood transfusion requirement among trauma patients on DOAC, including head trauma patients. Further studies on head trauma and specific subgroups of DOAC are recommended.

Participant-reported Warfarin Adherence in Community-based Pediatric Patients

Warfarin is the most commonly prescribed anticoagulant for children in the outpatient setting in Australia. Pediatric patients likely have different challenges to warfarin adherence compared with their adult counterparts; however, little is known about warfarin adherence among this population. This study aimed to understand warfarin adherence among community-based pediatric patients by using an online survey design. The survey instrument incorporated parent or patient self-reported warfarin doses missed in the preceding month, a validated warfarin adherence assessment tool, the 13-item Self-Efficacy for Appropriate Medication use Scale (SEAMS-13), and an open-ended question asking about the challenges of warfarin adherence. The indication of warfarin administration and patient's time in therapeutic range were obtained from medical records. The study recruited outpatients managed by a tertiary pediatric hospital who had previously consented to participate in warfarin research. In total, 53 families were contacted with 43 responses (81% response rate) and 41 completed surveys. The median age of the children from participating families was 10.6 years (range, 4.1 to 18.9 y). The majority of these children (n=42) used warfarin prophylactically and only 1 child used it to treat deep venous thrombosis. The time in therapeutic range achievement of this cohort was 64.4% (95% confidence interval, 58.7-70.2). The mean SEAMS-13 score was 33.5 (95% confidence interval, 31.75-35.37) and the total missed doses was 2.5%. Participants also identified barriers and enablers of warfarin adherence. This study was the first of its kind and thus it provides baseline data for future research. The warfarin adherence of this cohort was likely optimized because of frequent clinical contact and access to self-testing. Future studies are required to examine the different approaches aiming to improve the anticoagulant adherence after the emergence of direct oral anticoagulants with a wider therapeutic index and minimal monitoring that could contribute to less clinical contact.

Treatment preferences as basis for decision making in patients using direct oral anticoagulants in Spain

Treatment preferences are considered a relevant decision-making driver by the main atrial fibrillation (AF) guidelines. Direct Oral Anticoagulants (DOACs), considered as similar clinically, have administration differences useful for treatment individualization. Preferences, priorities and satisfaction of DOAC users were assessed through an observational, multicentric (25 hospitals), cross-sectional study including adult AF-patients (and/or caregivers) in Spain. Three study groups were considered according to DOAC posology preferences: (A) once-daily, with water; (B) once-daily, with food; (C) twice-daily. Overall, 332 patients and 55 caregivers were included. Mean (SD) age was 73.7 (10.7) years [58.7 (13.9) for caregivers]; 51.5% women [69.1% for caregivers]; 80.7% showed comorbidities and poly-pharmacy [6.6 (3.3) drugs/day]. No statistically significant differences were shown among study groups. Once-daily administration was preferred by 274 patients (82.5%) [60.8% (Group A); 21.7% (Group B); 17.5% (Group C)], and 47 caregivers (85.5%) [58.2% (Group A); 27.3% (Group B); 14.5% (Group C)]. Once-daily DOACs were prescribed in 42.8% of the patients. Bleeding risk was the main concern for both, patients and caregivers, followed by DOAC posology and interactions. Although treatment satisfaction (patients and caregivers) was high (9.0 and 9.1 points, respectively), match between individual treatment preferences and real prescriptions was only shown in 41.0% of AF-patients, evidencing a need for patient involvement on treatment decision-making. There is not a patient profile linked to treatment preferences, and clinical criteria must be the main driver for decision-making. However, for most AF-patients (elderly patients), aged, with comorbidity, poly-pharmacy and high cardiovascular risk, once-daily DOACs would be the preferred option.

Rivaroxaban as an Alternative Agent for Heparin-Induced Thrombocytopenia

Heparin-induced thrombocytopenia (HIT) is a high-risk adverse drug reaction because of its associated risk of life- and limb-threatening thrombosis. Rivaroxaban may be considered as an ideal nonheparin anticoagulant alternative for the management of HIT. In this preliminary retrospective study, the efficacy and safety of rivaroxaban to control the clinically suspected HIT (4Ts score 4 points or greater) were evaluated. Patients with chronic kidney disease, hepatic impairment, mechanical heart valves, and active bleeding were excluded. Forty-two eligible patients who received rivaroxaban for clinically suspected HIT were evaluated by medical records review, with 12-month follow-up after the first dose of rivaroxaban. End points included confirmed thrombosis (primary end point), mortality, and adverse treatment-related events. HIT-associated thrombosis was found in 17/42 (40.5%) patients before receiving rivaroxaban. After rivaroxaban therapy, platelet counts normalized in all patients, with only 1/42 (2.3%) patients developing new thrombosis. No hemorrhagic event was recorded in the patients. Twelve patients (28.6%) died, but the cause of death was not related to the thrombosis, hemorrhage, or adverse effects of rivaroxaban. Our findings are consistent with the available emerging data, suggesting that rivaroxaban is a safe and effective drug for the management of clinically suspected HIT. Rivaroxaban is a particularly valuable treatment option in developing countries, where there are issues of cost and availability of approved alternative agents.

Non-Vitamin K Oral Anticoagulants in Adults with Congenital Heart Disease: A Systematic Review

Adults with congenital heart disease (ACHD) experience more thromboembolic complications than the general population. We systematically searched and critically appraised all studies on the safety and efficacy of non-vitamin-K oral anticoagulants (NOACs) in adult patients with various forms of congenital heart disease. PubMed and the Cochrane Central Register of Controlled Trials (CENTRAL) were used, with duplicate extraction of data and risk of bias assessment. The Newcastle-Ottawa quality assessment scale was used to assess study quality. Three studies fulfilled the inclusion criteria and were analyzed. The total number of participants was 766, with a total follow-up of 923 patient-years. The majority of patients (77%) received a NOAC for atrial arrhythmias, while the remainder were prescribed NOACs for secondary (19%) or primary (4%) thromboprophylaxis. The annual rate of thromboembolic and major bleeding events was low: 0.98% (95% CI: 0.51-1.86) and 1.74% (95% CI: 0.86-3.49) respectively. In Fontan patients, the annual rate of thromboembolic and major bleeding events was 3.13% (95% CI: 1.18-8.03) and 3.17% (95% CI: 0.15-41.39) respectively. NOACs appear safe and effective in ACHD without mechanical prostheses. Additional studies are, however, needed to confirm their efficacy in complex ACHD, especially those with a Fontan-type circulation.

International normalized ratio (INR) values in patients receiving oral vitamin K antagonists and undergoing oral surgery: A clinical audit

INTRODUCTION

Dental extractions can be safely carried out on patients under vitamin K antagonists (VKAs) therapy, without stopping or changing the dosage, but the international normalized ratio (INR) needs to be monitored on the day of the intervention, showing adequate rates before proceeding.

OBJECTIVES

This study aims at evaluating INR values, measured before oral surgery procedures, to assess the rate of patients, under VKAs therapy, outside the therapeutic range.

MATERIALS AND METHODS

A clinical audit was carried out involving patients under VKAs, who needed minor oral surgery procedures, over a period of 18 months. The patient was instructed to not modify or suspend VKAs prior to the intervention. Before surgery, each patient fulfilled a questionnaire on dietary and oral hygiene habits, and a blood sample was collected for INR assessment (cut-off value for surgical procedure ≤3.5).

RESULTS

One hundred twenty-two patients were enrolled: 69 (56.6%) had an INR value within the established therapeutic range, 53 (43.4%) were out of range. No intra- or postsurgical major bleeding was recorded.

CONCLUSIONS

INR, measured on the same day of oral surgery, has the potential to prevent bleeding complications by the identification of those patients out of range, who may require adjusting the drug therapeutic dosage.

Prevention of Pulmonary and Venous Thromboembolism Post Coronary Artery Bypass Graft Surgery - Literature Review

Objective

The current review evaluates recent literature on the different aspects of prophylaxis in postoperative pulmonary and venous thromboembolism and their main risk factors.

Methods

The literature survey was carried out based on the PubMed data using the keywords “coronary artery bypass graft” and “venous thromboembolism” as components of the search field title.

Results

Studies reported several risk factors for postoperative thromboembolism including advanced age, postoperative immobilization, type of thromboprophylaxis, obesity, and location of the surgery.

Conclusion

According to the studies, tailored prophylaxis could be easily adapted to decrease the intensity and duration of postoperative thromboembolism in a patient with several disorders and comorbidities, especially in cardiovascular disease.

Relevance of physicochemical properties and functional pharmacology data to predict the clinical safety profile of direct oral anticoagulants

Direct oral anticoagulants (DOACs) have rapidly become the drug class of choice for anticoagulation therapy in secondary care. It is known that gastrointestinal hemorrhage are potential side effects of the DOAC drug class. In this study we have investigated the relevance of molecular structure and on/off-target pharmacology as a predictor of adverse drug reactions (ADRs) for the DOAC drug class. Use of the Reaxys MedChem module allowed for data mining of all possible reported off-target effects of the DOAC class members. For the first time, the MHRA Yellow card database in combination with prescribing rates in the United Kingdom (data for n = 30 566 936 DOAC Rx (up to 2017) and ADR data n = 22 275 (up to 2018)) were used for our data comparison of DOACs. From the underlying reported data, we were able to rank the DOACs in terms of the likely adverse events we would expect to observe. We identified potential risks of ADRs based on the DOACs pharmacology including the expected GI hemorrhage, but also the unexpected risk of stroke, pulmonary embolism and kidney injury. Statistically significant (P < .001) differences were found between all DOACs and their total number of ADRs. Although the risks are small, strong statistical correlation between observed pharmacology and national ADR data is observed in three out of the five areas of concern.

The Role of Antithrombotic Therapy in Heart Failure

Heart failure is a major contributor to global morbidity and mortality burden affecting approximately 1-2% of adults in developed countries, mounting to over 10% in individuals aged >70 years old. Heart failure is characterized by a prothrombotic state and increased rates of stroke and thromboembolism have been reported in heart failure patients compared with the general population. However, the impact of antithrombotic therapy on heart failure remains controversial. Administration of antiplatelet or anticoagulant therapy is the obvious (and well-established) choice in heart failure patients with cardiovascular comorbidity that necessitates their use, such as coronary artery disease or atrial fibrillation. In contrast, antithrombotic therapy has not demonstrated any clear benefit when administered for heart failure per se, i.e. with heart failure being the sole indication. Randomized studies have reported decreased stroke rates with warfarin use in patients with heart failure with reduced left ventricular ejection fraction, but at the expense of excessive bleeding. Non-vitamin K oral anticoagulants have shown a better safety profile in heart failure patients with atrial fibrillation compared with warfarin, however, current evidence about their role in heart failure with sinus rhythm is inconclusive and further research is needed. In the present review, we discuss the role of antithrombotic therapy in heart failure (beyond coronary artery disease), aiming to summarize evidence regarding the thrombotic risk and the role of antiplatelet and anticoagulant agents in patients with heart failure.

Polypharmacy, Adverse Outcomes, and Treatment Effectiveness in Patients ≥75 With Atrial Fibrillation

Background

Polypharmacy is highly prevalent in elderly people with chronic conditions, including atrial fibrillation (AF). The impact of polypharmacy on adverse outcomes and on treatment effectiveness in elderly patients with AF remains unaddressed.

Methods and Results

We studied 338 810 AF patients ≥75 years of age enrolled in the MarketScan Medicare Supplemental database in 2007–2015. Polypharmacy was defined as ≥5 active prescriptions at AF diagnosis (defined by the presence of International Classification of Diseases, Ninth Revision, Clinical Modification [ICD‐9‐CM] codes) based on outpatient pharmacy claims. AF treatments (oral anticoagulation, rhythm and rate control) and cardiovascular end points (ischemic stroke, bleeding, heart failure) were defined based on inpatient, outpatient, and pharmacy claims. Multivariable Cox models were used to estimate associations of polypharmacy with cardiovascular end points and the interaction between polypharmacy and AF treatments in relation to cardiovascular end points. Prevalence of polypharmacy was 52%. Patients with polypharmacy had increased risk of major bleeding (hazard ratio [HR], 1.16; 95% CI, 1.12–1.20) and heart failure (HR, 1.33; 95% CI, 1.29–1.36) but not ischemic stroke (HR, 0.96; 95% CI, 0.92–1.00), compared with those not receiving polypharmacy. Polypharmacy status did not consistently modify the effectiveness of oral anticoagulants. Rhythm control (versus rate control) was more effective in preventing heart failure hospitalization in patients not receiving polypharmacy (HR, 0.87; 95% CI, 0.76–0.99) than among those with polypharmacy (HR, 0.98; 95% CI, 0.91–1.07; P=0.02 for interaction).

Conclusion

Polypharmacy is common among patients ≥75 with AF, is associated with adverse outcomes, and may modify the effectiveness of AF treatments. Optimizing management of polypharmacy in AF patients ≥75 may lead to improved outcomes.

Trends in oral anticoagulant prescribing in individuals with type 2 diabetes mellitus: a population-based study in the UK

OBJECTIVE

To evaluate oral anticoagulant (OAC) prescribing trends in type 2 diabetes mellitus (T2DM) in the UK from 2001 to 2015.

DESIGN

A cross-sectional drug utilisation study.

SETTING

Electronic health records from The Health Improvement Network primary care database in the UK.

PARTICIPANTS

Individuals with T2DM who received a record of OAC prescription.

OUTCOME MEASURES

The prescribing trends of OAC medications in individuals with T2DM were examined from 2001 to 2015, stratified by age, gender and therapeutic classifications.

RESULTS

A total of 361 635 individuals with T2DM were identified, of whom 36 570 were prescribed OAC from 2001 to 2015. The prevalence of OAC prescribing increased by 50.0%, from 1781 individuals receiving OAC prescriptions (IROACP) (4.4 (95% CI 4.2 to 4.6) per 100 persons) in 2001, to 17 070 IROACP (6.6 (95% CI 6.5 to 6.7) per 100 persons) in 2015. The prevalence of warfarin prescribing decreased by 14.0%, from 1761 individuals receiving warfarin prescriptions (IRWP) (98.9 (95% CI 98.4 to 99.4) per 100 persons) in 2001, to 14 533 IRWP (85.1 (95% CI 84.6 to 85.7) per 100 persons) in 2015. This corresponded with increased prescribing of direct oral anticoagulants (DOACs), from 18 individuals receiving DOAC prescriptions (IRDOACP) (0.1 (95% CI 0.08 to 0.23) per 100 persons) in 2010, to 3016 IRDOACP (17.6 (95% CI 17.1 to 18.2) per 100 persons) in 2015, during the same period.

CONCLUSIONS

Prescribing of OACs in individuals with T2DM increased from 2001 to 2015. Since the introduction of DOACs, there has been a clear shift in prescribing towards these agents. Future studies are needed to assess the safety of coadministration of OAC medications and antidiabetic therapy with T2DM.

Cancer-associated venous thromboembolism: Treatment and prevention with rivaroxaban

Cancer-associated venous thromboembolism (VTE) is a frequent, potentially life-threatening event that complicates cancer management. Anticoagulants are the cornerstone of therapy for the treatment and prevention of cancer-associated thrombosis (CAT); factor Xa-inhibiting direct oral anticoagulants (DOACs; apixaban, edoxaban, and rivaroxaban), which have long been recommended for the treatment of VTE in patients without cancer, have been investigated in this setting. The first randomized comparisons of DOACs against low-molecular-weight heparin for the treatment of CAT indicated that DOACs are efficacious in this setting, with findings reflected in recent updates to published guidance on CAT treatment. However, the higher risk of bleeding events (particularly in the gastrointestinal tract) with DOACs highlights the need for appropriate patient selection. Further insights will be gained from additional studies that are ongoing or awaiting publication. The efficacy and safety of DOAC thromboprophylaxis in ambulatory patients with cancer at a high risk of VTE have also been assessed in placebo-controlled randomized controlled trials of apixaban and rivaroxaban. Both studies showed efficacy benefits with DOACs, but both studies also showed a nonsignificant increase in major bleeding events while on treatment. This review summarizes the evidence base for rivaroxaban use in CAT, the patient profile potentially most suited to DOAC use, and ongoing controversies under investigation. We also describe ongoing studies from the CALLISTO (Cancer Associated thrombosis-expLoring soLutions for patients through Treatment and Prevention with RivarOxaban) program, which comprises several randomized clinical trials and real-world evidence studies, including investigator-initiated research.

Adherence to oral anticoagulants among patients with atrial fibrillation: a systematic review and meta-analysis of observational studies

INTRODUCTION

Medications cannot exert their effect if not taken as prescribed by patients. Our objective was to summarise the observational evidence on adherence to oral anticoagulants (OACs) among patients with atrial fibrillation (AF).

METHODS

In March 2019, we systematically searched PubMed/Medline, Embase, CINAHL and PsycINFO (from inception) for observational studies measuring adherence, its determinants and impacts in patients with AF. Mean adherence measures and corresponding proportions of adherent patients were pooled using random effects models. Factors shown to be independently associated with adherence were extracted as well as the clinical and economic outcomes of adherence.

RESULTS

We included 30 studies. Pooled mean adherence scores of over half a million patients with AF 6 months and 1 year after therapy initiation were 77 (95% CI: 74-79) and 74 (68-79) out of 100, respectively. Drug-specific pooled mean adherence score at 6 months and 1 year were as follows: rivaroxaban: 78 (73-84) and 77 (69-86); apixaban: 77 (75-79) and 82 (74-89); dabigatran: 74 (69-79) and 75 (68-82), respectively. There was inadequate information on warfarin for inclusion in meta-analysis.Factors associated with increased adherence included: older age, higher stroke risk, once-daily regimen, history of hypertension, diabetes or stroke, concomitant cardiovascular medications, living in rural areas and being an experienced OAC user. Non-adherent patients were more likely to experience stroke and death, and incurred higher medical costs compared with patients with poor adherence.

CONCLUSIONS

Our findings show that up to 30% of patients with AF are non-adherent, suggesting an important therapeutic challenge in this patient population.

Current practice of anticoagulant in the treatment of splanchnic vein thrombosis secondary to acute pancreatitis

BACKGROUND

Severe acute pancreatitis is a common diagnosis in emergency general surgery and can be a cause of significant morbidity and mortality. A consequence of severe acute pancreatitis is thrombus in the splanchnic veins. These thrombi can potentially lead to bowel ischemia or hepatic failure. However, another complication of severe acute pancreatitis is retroperitoneal bleeding. At this time, it is unclear if treating patients for splanchnic vein thrombosis in the context of severe acute pancreatitis is associated with any outcome benefit. A systematic review might clarify this question.

DATA SOURCES

A two-fold search strategy (one broad and one precise) looked at all published literature. The review was registered on PROSPERO (ID: CRD42018102705). MEDLINE, EMBASE, PubMed, Cochrane and Web of Science databases were searched and potentially relevant papers were reviewed independently by two researchers. Any disagreement was reviewed by a third independent researcher. Primary outcome was reestablishment of flow in the thrombosed vein versus bleeding complications.

RESULTS

Of 1462 papers assessed, a total of 16 papers were eligible for inclusion. There were no randomized controlled trials, 2 were case series, 5 retrospective single-center studies and 9 case reports. There were a total of 198 patients in these studies of whom 92 (46.5%) received anticoagulation therapy. The rates of recanalization of veins in the treated and non-treated groups was 14% and 11% and bleeding complications were 16% and 5%, respectively. However, the included studies were too heterogeneous to undertake a meta-analysis.

CONCLUSIONS

The systematic review highlights the lack evidence addressing this clinical question. Therefore a randomized controlled trial would be appropriate to undertake.

Review of Therapeutic Options for the Prevention of VTE in Total Joint Arthroplasty

Hip and knee arthroplasty patients are at high risk of perioperative venous thromboembolic events (VTE). VTE has been well studied in this population and it is recommended that total joint arthroplasty recipients receive chemoprophylactic anticoagulation due to risk factors inherent to the surgical intervention. There are few concise resources for the orthopedic surgeon that summarize data regarding post-operative anticoagulation in the context of currently available therapeutic options and perioperative standards of practice. The periodic reexamination of literature is essential as conclusions drawn from studies predating perioperative protocols that include early mobilization and sequential compression devices as standards of practice in total joint arthroplasty are no longer generalizable to modern-day practice. We reviewed a large number of recently published research studies related to post-operative anticoagulation in total joint arthroplasty populations that received a high Level of Evidence grade. Current literature supports the use of oral aspirin regimens in place of more aggressive anticoagulants, particularly among low risk patients. Oral aspirin regimens appear to have the additional benefit of lower rates of bleeding and wound complications. Less consensus exists among high risk patients and more potent anticoagulants may be indicated. However, available evidence does not demonstrate clear superiority among current options, all of which may place patients at a higher risk of bleeding and wound complications. In this situation, chemoprophylactic selection should reflect specific patient needs and characteristics.

Quality of Warfarin Anticoagulation in Indigenous and Non-Indigenous Australians With Atrial Fibrillation

BACKGROUND

Studies have shown that suboptimal anticoagulation quality, as measured by time in therapeutic range (TTR), affects a significant percentage of patients with atrial fibrillation (AF). However, TTR has not been previously characterised in Indigenous Australians who experience a greater burden of AF and stroke.

METHOD

Indigenous and non-Indigenous Australians with AF on warfarin anticoagulation therapy were identified from a large tertiary referral centre between 1999 and 2012. Time in therapeutic range was calculated as a proportion of daily international normalised ratio (INR) values between 2 and 3 for non-valvular AF and 2.5 to 3.5 for valvular AF. INR values between tests were imputed using the Rosendaal technique. Linear regression models were employed to characterise predictors of TTR.

RESULTS

Five hundred and twelve (512) patients with AF on warfarin were included (88 Indigenous and 424 non-Indigenous). Despite younger age (51±13 vs 71±12 years, p<0.001), Indigenous Australians had greater valvular heart disease, diabetes, and alcohol excess compared to non-Indigenous Australians (p<0.05 for all). Time in therapeutic range was significantly lower in Indigenous compared to non-Indigenous Australians (40±29 vs 50±31%, p=0.006). Univariate predictors of poorer TTR included Indigenous ethnicity, younger age, diuretic use, and comorbidities, such as valvular heart disease, heart failure and chronic obstructive pulmonary disease (p<0.05 for all). Valvular heart disease remained a significant predictor of poorer TTR in multivariate analyses (p=0.004).

CONCLUSION

Indigenous Australians experience particularly poor warfarin anticoagulation quality. Our data also suggest that many non-Indigenous Australians spend suboptimal time in therapeutic range. These findings reinforce the importance of monitoring warfarin anticoagulation quality to minimise stroke risk.

Digital Competencies and Attitudes Toward Digital Adherence Solutions Among Elderly Patients Treated With Novel Anticoagulants: Qualitative Study

BACKGROUND

Nonadherence to medication is a driver of morbidity and mortality, and complex medication regimens in patients with chronic diseases foster the problem. Digital technology might help, but despite numerous solutions being developed, none are currently widely used, and acceptance rates remain low, especially among the elderly.

OBJECTIVE

This study aimed to better understand and operationalize how new digital solutions can be evaluated. Particularly, the goal was to identify factors that help digital approaches targeting adherence to become more widely accepted.

METHODS

A qualitative study using a conceptual grounded theory approach was conducted. We included patients aged 65 years and older who routinely took new oral anticoagulants. To generate theses about the digital competencies of the target group with daily medication intake, face-to-face interviews were conducted, recorded, and anonymized. After coding the interviews, categories were generated, discussed, and combined with several theses until saturation of the statements was reached.

RESULTS

The methodological approach led to the finding that after interviews in 20 of 77 potentially available patients, a saturation of statements was reached. The average patient's age was 75 years, and 50% (10/20) of the subjects were female. The data identified five main coding categories-Diseases and medicine, Technology, Autonomy, Patient narrative, and Attitude toward technologies-each including positive and negative subcategories. Main categories and subcategories were summarized as Adherence Radar, which can be considered as a framework to assess the potential of adherence solutions in the process of prototyping and can be applied to all adherence tools in a holistic manner.

CONCLUSIONS

The Adherence Radar can be used to increase the acceptance rate of digital solutions targeting adherence. For a patient-centric design, an app should be adapted to the individual patient's needs. According to our results, this application should be based on gender and educational background as well as the individual physician-patient relationship. If used in a proper, individualized manner, digital adherence solutions could become a new cornerstone for the treatment of chronically ill individuals.

Comparative efficacy and safety of warfarin care bundles and novel oral anticoagulants in patients with atrial fibrillation: a systematic review and network meta-analysis

Warfarin care bundles (e.g. genotype-guided warfarin dosing, patient’s self-testing [PST] or patient’s self-management [PSM] and left atrial appendage closure) are based on the concept of combining several interventions to improve anticoagulation care. NOACs are also introduced for stroke prevention in atrial fibrillation (SPAF). However, these interventions have not been compared in head-to-head trials yet. We did a network meta-analysis based on a systematic review of randomized controlled trials comparing anticoagulant interventions for SPAF. Studies comparing these interventions in adults, whether administered alone or as care bundles were included in the analyses. The primary efficacy outcome was stroke and the primary safety outcome was major bleeding. Thirty-seven studies, involving 100,142 patients were assessed. Compared to usual care, PSM significantly reduced the risk of stroke (risk ratio [RR] 0.24, 95% CI 0.08–0.68). For major bleeding, edoxaban 60 mg (0.80, 0.71–0.90), edoxaban 30 mg (0.48, 0.42–0.56), and dabigatran 110 mg (0.81, 0.71–0.94) significantly reduced the risk of major bleeding compared with usual warfarin care. Cluster rank plot incorporating stroke and major bleeding outcomes indicates that some warfarin care bundles perform as well as NOACs. Both interventions are therefore viable options to be considered for SPAF. Additional studies including head-to-head trials and cost-effectiveness evaluation are still warranted.

Rivaroxaban Treatment in Two Breastfeeding Mothers: A Case Series

Background: Rivaroxaban (Xarelto) is a reversible direct factor Xa inhibitor used for the treatment and prevention of coagulation in numerous syndromes. There is very limited information available on the transfer of rivaroxaban into human breast milk. Case Report: This study determined the drug concentration-time profile of rivaroxaban in milk samples collected from two lactating mothers consuming 15 mg twice daily. After 21 days, each mother transitioned to 20 mg once daily. Levels in milk were measured using liquid chromatography mass spectrometry and analysis was done for both dosages. The maximum concentration of rivaroxaban observed for the 15 mg dose was 0.3 ± 0.02 μg/mL and that for the 20 mg dose was 0.26 ± 0.01 μg/mL. The relative infant dose (RID) was calculated to be 5% and 4%, respectively. Discussion: This relatively low infant dose is probably explained by the high plasma protein binding of rivaroxaban and its subsequent poor penetration into human milk. The results indicate that rivaroxaban receded to minimum concentration over a period of 12 hours. Conclusions: In these two cases, we found the levels of rivaroxaban in milk to be quite low, and the RID to be 5% of the maternal dose. Although the levels detected were low, rivaroxaban does transfer into breast milk. Caution should be exercised until further studies are conducted and report the safety profile of rivaroxaban in breastfeeding infants.

Non-vitamin K antagonist oral anticoagulants (NOACs) post-percutaneous coronary intervention: a network meta-analysis

BACKGROUND

Clinicians must balance the risks of bleeding and thrombosis after percutaneous coronary intervention (PCI) in people with an indication for anticoagulation. The potential of non-vitamin K antagonists (NOACs) to prevent bleeding complications is promising, but evidence remains limited.

OBJECTIVES

To review the evidence from randomised controlled trials assessing the efficacy and safety of non-vitamin K antagonist oral anticoagulants (NOACs) compared to vitamin K antagonists post-percutaneous coronary intervention (PCI) in people with an indication for anticoagulation.

SEARCH METHODS

We identified studies by searching CENTRAL, MEDLINE, Embase, the Conference Proceedings Citation Index - Science and two clinical trials registers in February 2019. We checked bibliographies of identified studies and applied no language restrictions.

SELECTION CRITERIA

We searched for randomised controlled trials (RCT) that compared NOACs and vitamin K antagonists for people with an indication for anticoagulation who underwent PCI.

DATA COLLECTION AND ANALYSIS

Two review authors independently checked the results of searches to identify relevant studies, assessed each included study, and extracted study data. We conducted random-effects, pairwise analyses using Review Manager 5 and network meta-analyses (NMA) using the R package 'netmeta'. We ranked competing treatments by P scores, which are derived from the P values of all pairwise comparisons, and allow ranking of treatments on a continuous 0 to 1 scale.

MAIN RESULTS

We identified nine RCTs that met the inclusion criteria, but four were ongoing trials, and were not included in this analysis. We included five RCTs, with 8373 participants, in the NMA (two RCTs compared apixaban to a vitamin K antagonist, two RCTs compared rivaroxaban to a vitamin K antagonist, and one RCT compared dabigatran to a vitamin K antagonist). Very low- to moderate-certainty evidence suggests little or no difference between NOACs and vitamin K antagonists in death from cardiovascular causes (not reported in the dabigatran trial), myocardial infarction, stroke, death from any cause, and stent thrombosis. Apixaban (RR 0.85, 95% CI 0.77 to 0.95), high dose rivaroxaban (RR 0.86, 95% CI 0.74 to 1.00), and low dose rivaroxaban (RR 0.80, 95% CI 0.68 to 0.92) probably reduce the risk of recurrent hospitalisation compared with vitamin K antagonists. No studies looked at health-related quality of life. Very low- to moderate-certainty evidence suggests that NOACs may be safer than vitamin K antagonists in terms of bleeding. Both high dose dabigatran (RR 0.53, 95% CI 0.29 to 0.97), and low dose dabigatran (RR 0.38, 95% CI 0.21 to 0.70) may reduce major bleeding more than vitamin K antagonists. High dose dabigatran (RR 0.83, 95% CI 0.72 to 0.96), low dose dabigatran (RR 0.66, 95% CI 0.58 to 0.75), apixaban (RR 0,67 , 95% Cl 0.51 to 0.88), high dose rivaroxaban (RR 0.66, 95% CI 0.52 to 0.83), and low dose rivaroxaban (RR 0.71, 95% CI 0.57 to 0.88) probably reduce non-major bleeding more than vitamin K antagonists. The results from the NMA were inconclusive between the different NOACs for all primary and secondary outcomes.

AUTHORS' CONCLUSIONS

Very low- to moderate-certainty evidence suggests no meaningful difference in efficacy outcomes between non-vitamin K antagonist oral anticoagulants (NOAC) and vitamin K antagonists following percutaneous coronary interventions (PCI) in people with non-valvular atrial fibrillation. NOACs probably reduce the risk of recurrent hospitalisation for adverse events compared with vitamin K antagonists. Low- to moderate-certainty evidence suggests that dabigatran may reduce the rates of major and non-major bleeding, and apixaban and rivaroxaban probably reduce the rates of non-major bleeding compared with vitamin K antagonists. Our network meta-analysis did not show superiority of one NOAC over another for any of the outcomes. Head to head trials, directly comparing NOACs against each other, are required to provide more certain evidence.

Clinically relevant drug interactions between newer antidepressants and oral anticoagulants

Introduction: This is a review of the drug interactions (DIs) between newer antidepressants and oral anticoagulants (OACs): vitamin K antagonists (VKAs) and direct-acting OACs (DOACs).Areas covered: Articles were obtained from PubMed searches performed for each of the newer antidepressants and oral anticoagulants. The basic pharmacokinetic and pharmacodynamic mechanisms for DIs with these drugs were summarized. Some newer antidepressants are inhibitors of a number of cytochrome P450 (CYP) isoforms and many antidepressants appear to have potential to impair serotonin platelet function and increase bleeding risk.Expert opinion: Clinicians should not forget that the DIs between newer antidepressants and VKAs can be potentially lethal. Among SSRIs, fluoxetine and fluvoxamine appear to be associated with the highest DI risk with warfarin, the most commonly prescribed VKA worldwide. Case reports featuring duloxetine, mirtazapine and trazadone suggested potential for interaction with warfarin. As CYP3A4 is an important metabolic pathway for all DOACs except dabigatran, it appears reasonable to recommend avoiding the co-prescription of fluoxetine and fluvoxamine (weak to moderate CYP3A4 inhibitors) and St John's wort (CYP3A4 inducer). Many package inserts for the newer antidepressants include a warning regarding an increased risk of bleeding events with concomitant use of these agents with OACs.

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.

Cost-effectiveness of warfarin care bundles and novel oral anticoagulants for stroke prevention in patients with atrial fibrillation in Thailand

INTRODUCTION

Novel oral anticoagulants (NOACs) and warfarin care bundles (e.g. genotyping, patient self-testing or self-management) are alternatives to usual warfarin care for stroke prevention in patients with atrial fibrillation (AF). We aim to evaluate the cost-effectiveness of NOACs and warfarin care bundles in patients with AF in a middle-income country, Thailand.

MATERIALS AND METHODS

A Markov model was used to evaluate the economic and treatment outcomes of warfarin care bundles and NOACs compared with usual warfarin care. Cost-effectiveness was assessed from a societal perspective over a lifetime horizon with 3% discount rate in a hypothetical cohort of 65-year-old atrial fibrillation patients. Input parameters were derived from published literature, meta-analysis and local data when available. The outcome measure was incremental cost per quality-adjusted life years (QALY) gained (ICER).

RESULTS

Using USD5104 as the threshold of willingness-to-pay per QALY, patient's self-management of warfarin was cost-effective when compared to usual warfarin care, with an ICER of USD1395/QALY from societal perspective. All NOACs were not cost-effective in Thailand, with ICER ranging from USD8678 to USD14,247/QALY. When compared to the next most effective intervention, patient's self-testing and genotype-guided warfarin dosing were dominated. In the cost-effectiveness acceptability curve, patient's self-management had the highest probability of being cost-effective in Thailand, approximately 78%. Results were robust over a range of inputs in sensitivity analyses.

CONCLUSIONS

In Thailand, NOACs were unlikely to be cost-effective at current prices. Conversely, patient's self-management is a highly cost-effective intervention and may be considered for adoption in developing regions with resource-limited healthcare systems.

Standardized warfarin monitoring decreases adverse drug reactions

Background

While warfarin is the most commonly prescribed medication to prevent thromboembolic disorders, the risk of adverse drug reactions (ADR) poses a serious concern. This prospective study evaluated how primary care providers (PCP) and cardiologists at our Institution managed patients treated with warfarin with the goal of decreasing the number of warfarin ADRs.

Methods

A multidisciplinary anticoagulation task force was established at our Institution in 2014 to standardize warfarin monitoring and management. Between 2013 and 2017, we analyzed patients who were prescribed warfarin by their PCP or cardiologist upon hospital discharge and in the ambulatory setting to determine the international normalized ratio (INR) within 5, 10, and 30 days after discharge, time in therapeutic range (TTR), number of severe warfarin ADRs, and total and average cost reduction of all severe warfarin ADRs to determine whether there was an organizational cost savings following the implementation of standardized warfarin care.

Results

The warfarin ADR rate significantly decreased over the 5-year period, from 3.8 to 0.98% (p < 0.0001). The proportion of warfarin prescriptions out of all anticoagulants significantly decreased, from 72.2 to 42.1% (p < 0.001). The proportion of individuals who received an INR at 5, 10, and 30 days after hospital discharge compared to the total number of patients prescribed warfarin significantly increased (p < 0.001). The total cost of severe warfarin ADRs decreased by 57.6% between 2013 and 2017.

Conclusions

This study serves as a model to reduce the number of severe warfarin ADRs by the following tactics: (1) educating PCPs and cardiologists about evidence-based guidelines for warfarin management, (2) increasing the use of our Institution’s electronic warfarin module, and (3) enhancing patient compliance with obtaining INR.

Direct oral anticoagulants are effective and safe for the treatment of venous thromboembolism associated with gynecological cancers

OBJECTIVE

To retrospectively review the efficacy and safety of novel direct oral anticoagulants (DOACs) and compare the results with those of vitamin K antagonists (VKA) when used in clinical practice to treat venous thromboembolism (VTE) because there is insufficient evidence regarding its use in patients with gynecological cancers.

METHODS

A study was conducted of patients diagnosed with gynecological cancers at Osaka University Hospital between January 2010 and December 2017. The medical records of those who suffered from deep venous thrombosis (DVT) and/or pulmonary embolism (PE) were retrospectively reviewed.

RESULTS

Among the 1698 cases of gynecological cancers, 107 (6.3%) cases were diagnosed as having VTE. A total of 34 (31.8%) patients presented DVT plus PE and 73 (68.2%) patients had DVT alone. Fifty-four cases were treated with DOACs and 53 with VKA. Although 3 of the 53 patients (5.7%) in the VKA group developed recurrent VTE, only 1 (1.9%) patient in the DOAC group showed clinically relevant bleeding from a tumor penetrating the rectum. DOACs were non-inferior to VKA with respect to the composite outcome, including recurrent venous thrombosis and relevant bleeding (hazard ratio 0.31, 95% confidence interval 0.03-3.12, P=0.363).

CONCLUSION

DOACs can be effectively and safely used in VTE patients with gynecological cancers.

Mesenteric venous thrombosis as a complication of appendicitis in an adolescent: A case report and literature review

RATIONALE

Mesenteric venous thrombosis is an uncommon but potentially fatal condition that can cause bowel ischemia. It results from a systemic hypercoagulable state or abdominal infection draining into the portal venous system. Several cases regarding portomesenteric venous thrombosis as a complication of appendicitis were reported in adults, but there are far fewer reports in pediatric patients. The mortality rate of the condition is high if untreated, especially in children, reaching up to 50%.

PATIENT CONCERNS

A healthy 15-year-old male with no significant past medical history presented with right lower quadrant pain, lethargy, and fever. The computed tomography scan showed a focal thrombosis at the superior mesenteric vein branch and an inflamed appendix.

DIAGNOSES

Mesenteric venous thrombosis complicating acute appendicitis.

INTERVENTIONS

Intravenous antibiotics along with anticoagulants and laparoscopic appendectomy OUTCOMES:: After 1 month, a follow-up ultrasonography revealed full resolution of the thrombosis.

LESSONS

Appendicitis is one of the most frequently encountered causes of pediatric surgical emergencies; therefore, physicians should be conscious of mesenteric venous thrombosis as a possible complication of acute appendicitis, irrespective of whether patients have thrombophilic conditions or not.

Efficacy and safety of non-vitamin K antagonist oral anticoagulants post-kidney transplantation

BACKGROUND

Novel oral anticoagulants (NOACs) were developed as alternatives to vitamin K antagonists, primarily warfarin, as they do not require routine monitoring and have limited drug-drug and drug-food interactions. However, the efficacy and safety of these agents in kidney transplantation are not well studied.

AIM

To assess the profile and safety of NOACs for patients who had kidney transplantation, and to provide recommendations and guidelines on therapeutic strategies in these patients.

METHODS

This was a retrospective study carried out among adult patients who were actively on the following NOACs (apixaban, rivaroxaban or dabigatran) in our renal transplantation program from December 2015 to December 2016. The patients were identified primarily through electronic medical record system (patient data linkage). Data on the clinical and laboratory profile of the patients were retrieved and analyzed with SPSS 22.0.

RESULTS

Complete data on 42 renal transplant patients were retrieved: 59.5% males, 90.5% were whites and 66.7% were older than 60 years old. The mean duration since renal transplantation of the patients was 8.8 ± 7.4 years. The most common risk factors for the development of end-stage renal disease in the subjects were hypertension (19.0%), polycystic kidney disease (19.0%), followed by diabetic nephropathy (16.7%) and chronic glomerulonephritis (16.7%). The main indications for NOACs use in the cohort were atrial fibrillation in 25 patients (59.5%) and venous thromboembolism in 10 patients (23.8%). Overall, 29 patients (69%) were treated with apixaban, 10 patients (23.8%) with rivaroxaban and 3 patients (7.14%) with dabigatran. No (0%) thromboembolic events were observed during the one-year period, but 3 (7.1%) bleeding events occurred in the cohort consisting of 1 patient treated with rivaroxaban 15 mg daily and 2 patients who received apixaban 2.5 mg twice daily. There were no significant changes in serum tacrolimus level three days after the initiation of NOACs among patients treated with tacrolimus (pre- and post-NOACs tacrolimus levels were 7.2516 and 7.8867 ng/mL, P = 0.55, respectively). Also, after one-year of treatment with NOACs there were no significant changes in the pre- and post-NOACs serum creatinine level (P = 0.772) and estimated glomerular filtration rates (P = 0.232).

CONCLUSION

No thromboembolic events or significant changes in renal profile were observed in our cohort of kidney transplant recipients who were treated with NOACs for at least a year. However, a few bleeding events were observed. This calls for further well-planned randomized controlled trials to assess the efficacy and safety of NOACs among renal transplant recipients.

Direct-Acting Oral Anticoagulants and Their Reversal Agents-An Update

Background: Over the last ten years, a new class of drugs, known as the direct-acting oral anticoagulants (DOACs), have emerged at the forefront of anticoagulation therapy. Like the older generation anticoagulants, DOACs require specific reversal agents in cases of life-threatening bleeding or the need for high-risk surgery. Methods: Published literature was searched, and information extracted to provide an update on DOACS and their reversal agents. Results: The DOACs include the direct thrombin inhibitor—dabigatran, and the factor Xa inhibitors—rivaroxaban, apixaban, edoxaban, and betrixaban. These DOACs all have a rapid onset of action and each has a predictable therapeutic response requiring no monitoring, unlike the older anticoagulants, such as warfarin. Two reversal agents have been approved within the last five years: idarucizumab for the reversal of dabigatran, and andexanet alfa for the reversal of rivaroxaban and apixaban. Additionally, ciraparantag, a potential “universal” reversal agent, is currently under clinical development. Conclusions: A new generation of anticoagulants, the DOACs, and their reversal agents, are gaining prominence in clinical practice, having demonstrated superior efficacy and safety profiles. They are poised to replace traditional anticoagulants including warfarin.

Critical Issues and Recent Advances in Anticoagulant Therapy: A Review

As the population is aging, clinicians are coming across more patients with atrial fibrillation and venous thromboembolism requiring anticoagulation to prevent stroke and systemic embolisms. Due to a high prevalence and unfavorable consequences, managing thromboembolic diseases have become areas of clinical concern. Traditional anticoagulants like heparin, low molecular weight heparin and warfarin have been used for the prevention and treatment of venous and arterial thromboses. But, issues of bleeding, parenteral route of administration, or the need for frequent monitoring due to variability in response respectively limit their use. The article gives an overview of coagulation along with existing therapy available for anticoagulation and to present an update on utility and recent advances of new oral anticoagulants (NOACs) beginning from their nomenclature, advantages, disadvantages, precautions and contraindications compared with those of vitamin K antagonists (VKAs) based on a large number of recent studies and clinical trials.

Safety of direct oral anticoagulants in patients with cirrhosis: a systematic review and meta-analysis

INTRODUCTION

Direct oral anticoagulants (DOACs) are effective treatment for venous thromboembolism. However, safety data in patients with cirrhosis are limited. We conducted a systematic review and meta-analysis to evaluate the safety of DOACs compared with warfarin or low-molecular weight heparin in patients with cirrhosis.

METHODS

A systematic literature search was performed using MEDLINE and EMBASE from inception up to June 2018. We included prospective and retrospective studies involving adults ≥18 years with cirrhosis in whom anticoagulants were indicated for any indications. Primary outcome was all-cause bleeding events. Secondary outcome was major bleeding. Pooled risk ratio, pooled odd ratios and 95% confidence intervals (CIs) were calculated using random-effects model.

RESULTS

Five studies with a total of 447 patients were included in the analysis. When compared with controls, the use of DOACs in cirrhotic patients did not show a significant difference in all-cause bleeding (risk ratio 0.72; 95% CI, 0.32-1.63). There was also no significant difference in major bleeding between both groups (odd ratio 0.46; 95% CI, 0.10-2.09).

CONCLUSIONS

Our study demonstrates that, compared to those who were treated with traditional anticoagulants, cirrhotic patients who were treated with DOACs had no significant increase risk of all-cause bleeding and major bleeding.

Differences in the quality of oral anticoagulation therapy with vitamin K antagonists in German GP practices - results of the cluster-randomized PICANT trial (Primary Care Management for Optimized Antithrombotic Treatment)

Background

In Germany, patients receiving oral anticoagulation (OAC) are often treated by general practitioners (GPs), and large proportions of patients receive vitamin K antagonists (VKAs). The quality of OAC in German GP practices, differences between various practices, and improvement potential through implementation of case management, have not yet been investigated satisfactorily.

Based on results of a cluster-randomized controlled trial, we aimed to assess whether OAC quality can be improved, any variations between practices exist and determine practice- and patient-level factors.

Methods

The PICANT trial (2012–2015) was performed in 52 GP practices in Hesse, Germany. Adult patients with long-term indication for OAC received best practice case management in the intervention group. International normalized ratio (INR) values were recorded from anticoagulation passes. The Rosendaal method was used to calculate Time in Therapeutic Range (TTR) at patient level, and mean pooling to obtain center-specific TTR (cTTR) at practice level. The quality of OAC was assessed by TTR and cTTR. Linear model analyses were used to investigate associations between practice−/ patient-level factors and TTR.

Results

Inclusion of 736 patients (49.6% intervention and 50.4% control patients); 690 (93.8%) received phenprocoumon. Within 24 months, the TTR was 75.1% (SD 17.6) in the intervention versus 74.3% (SD 17.8) in the control group (p = 0.670). The cTTR averaged 75.1% (SD 6.5, range: 60.4 to 86.7%) in the intervention versus 74.3% (SD 7.2, range: 52.7 to 85.7%) in the control group (p = 0.668). At practice level, the TTR was significantly lower in practices with a male physician and certification in quality management. At patient level, the TTR was significantly higher in patients with moderate to high compliance, in men, and in patients that performed self-management. The TTR was significantly lower in patients with certain comorbidities, and who were hospitalized.

Conclusions

The intervention did not effectively improve OAC quality compared to routine care. Quality of INR control was generally good, but considerable variation existed between GP practices. The variability indicates optimization potential in some practices. The demonstrated association between patient-level factors and TTR highlights the importance of considering patient characteristics that may impede achieving high quality therapeutic outcomes.

Trial registration

ISRCTN registry, ISRCTN41847489, registered 27 February 2012.

Electronic supplementary material

The online version of this article (10.1186/s12913-019-4372-y) contains supplementary material, which is available to authorized users.

The Guideline-Policy Gap in Direct-Acting Oral Anticoagulants Usage in Atrial Fibrillation: Evidence, Practice, and Public Policy Considerations

Atrial fibrillation has a high disease burden-both in prevalence and associated consequences. Despite anticoagulation being an effective treatment in atrial fibrillation, stroke prevention is slow to reflect evidence-based practice. Real-world data reveal a substantial portion of patients who would benefit from anticoagulation, yet do not receive it adequately or at all. A large part of this suboptimal treatment is due to the underutilization of direct oral anticoagulants (DOACs). In response to abundant evidence published over a short timeframe, international guidelines have adopted DOAC usage ahead of policy and fund holders. This paper reviews the evidence and values that influence published guidelines, patient-physician decision making, and policy framework on DOAC usage. An important factor is the access gap between patients who qualify for DOAC according to evidence-based guidelines and the subset of this cohort who are eligible for DOAC based on government funded policy. We analyse the Canadian health system in detail-including drug approval and funding process. Health care systems in other countries are explored, with emphasis on similar universal health care systems that may help overcome barriers common to Canada. We will discuss strategies to: (1) improve awareness of the risk and preventability of stroke; (2) enable physicians to provide evidence-based DOAC usage; (3) empower patients to improve adherence and persistence; (4) collect real-life data that encourages patient self-monitoring, physician outcomes auditing, and building evidence that is useful for policy makers; and (5) use postmarketing data in negotiating shared risk management between pharmaceuticals and government to improve access to DOACs.