Adherence to a new oral anticoagulant treatment prescription: dabigatran etexilate

Self-reported adherence to direct oral anticoagulants versus warfarin therapy in a specialized thrombosis service-a cross-sectional study of patients in a Canadian Health Region

PURPOSE

Direct oral anticoagulants (DOACs) have a better safety and efficacy profile than warfarin and are currently recommended for stroke prevention in non-valvular atrial fibrillation (AF) and treatment of venous thromboembolism (VTE). Given that DOACs do not require regular laboratory monitoring compared to warfarin, patients' interactions with the health care system is reduced. Adequate adherence to DOACs is important and reported adherence to anticoagulation is unclear in clinical practice. This study aims to assess self-reported adherence to oral anticoagulants in a specialized Adult Outpatient Thrombosis Service (TS).  METHODS: This cross-sectional study included patients aged ≥ 18 years who were prescribed an oral anticoagulant and had attended at least one appointment with an Adult Outpatient Thrombosis Service (TS) between October 10, 2017, and May 31, 2019. Adherence to oral anticoagulant therapy was assessed using the 12-item validated Adherence to Refills and Medications Scale (ARMS) score. Logistic regression analyses were used to evaluate association between patient characteristics and medication adherence. Adherence rates in DOACs and warfarin were compared.

RESULTS

Three hundred and ninety-nine patients completed and returned the survey. Of the 399 who completed the survey, 74% were prescribed DOACs and 26% received warfarin. Most of the patients (89.3%) were ≥ 50 years of age and half (57.3%) were male. About two-thirds (67%) had at least post-secondary education. The duration of anticoagulation use differed between patients on DOAC and warfarin; a greater proportion of those who had used anticoagulants for less than 1 year was on DOACs compared to warfarin (20.9% vs 4.9%, p = 0.001). For patients who had been on anticoagulation for > 5 years, the proportion of warfarin patients was greater than DOAC (57.8% vs 20.5%, p = 0.001). Self-reported adherence to oral anticoagulant therapy using the 12-item ARMS scale for warfarin and DOACs were 87.3% and 90.9%, respectively. Among the warfarin users, patient satisfaction with TS was associated with medication adherence (OR = 0.22; 95% CI: 0.05-0.89).

CONCLUSIONS

Self-reported medication adherence was similar between warfarin and DOACs. Since suboptimal adherence is associated with poor clinical outcomes and increased costs, various stakeholders should emphasize the importance of medication adherence to oral anticoagulants at each patient encounter.

Direct Oral Anticoagulants: From Randomized Clinical Trials to Real-World Clinical Practice

Direct oral anticoagulants (DOACs) are a more manageable alternative than vitamin K antagonists (VKAs) to prevent stroke in patients with nonvalvular atrial fibrillation and to prevent and treat venous thromboembolism. Despite their widespread use in clinical practice, there are still some unresolved issues on optimizing their use in particular clinical settings. Herein, we reviewed the current clinical evidence on uses of DOACs from pharmacology and clinical indications to safety and practical issues such as drugs and food interactions. Dabigatran is the DOAC most affected by interactions with drugs and food, although all DOACs demonstrate a favorable pharmacokinetic profile. Management issues associated with perioperative procedures, bleeding treatment, and special populations (pregnancy, renal and hepatic impairment, elderly, and oncologic patients) have been discussed. Literature evidence shows that DOACs are at least as effective as VKAs, with a favorable safety profile; data are particularly encouraging in using low doses of edoxaban in elderly patients, and edoxaban and rivaroxaban in the treatment of venous thromboembolism in oncologic patients. In the next year, DOAC clinical indications are likely to be further extended.

An Analysis of Perceived and Actual Anticoagulant Knowledge among Independent Pharmacy Patients

Background:

Deficits in knowledge of parameters surrounding anticoagulant therapy administration carry substantial risks for patient harm. Patients prescribed anticoagulants may overestimate their knowledge of anticoagulant use principles. The purpose of this study was to analyze independent pharmacy patients’ perceived versus actual knowledge of their anticoagulation therapies.

Methods:

A 15-item survey across a dual-site pharmacy location evaluated patients’ confidence in their understanding of anticoagulant prescribing parameters and their awareness of measures to take to safeguard anticoagulant therapy routines. A pharmacist reviewed patient responses to survey items referencing actual understanding of anticoagulant therapies at the conclusion of the survey. Data analyses occurred by gender, age, ethnicity, location, living situation, self-management of anticoagulants, patient perception of anticoagulant safety, and reported receipt of anticoagulant education. Linear regressions were used for statistical analyses, with significance set at p<.05.

Results:

During the span of three months, 45 patients, 20 females and 25 males, completed the survey. Perceived anticoagulant knowledge did not differ significantly by demographics. Actual anticoagulant knowledge declined by over 20% between age groups 60-69 and 80-89 years old. African Americans displayed 10% lower actual anticoagulant knowledge than Caucasian Americans.

Conclusions:

This study revealed gaps in knowledge of anticoagulants among patients at an independent pharmacy. An appeal remains for more strategies to assist with knowledge of anticoagulant regimens. Healthcare institutions should continue to incorporate programs geared towards ongoing anticoagulant education, such as question and answer sessions, along with peer support mediums that foster optimal outcomes.

A composite nanocarrier to inhibit precipitation of the weakly basic drug in the gastrointestinal tract

For weakly basic drugs, the sharp decrease of drug solubility and the following drug precipitation after drugs transferring from the gastric fluid to the intestinal fluid in the gastrointestinal (GI) tract is a main reason for the poor oral bioavailability of drugs. Here, an anticoagulant dabigatran etexilate (DE) was used as a model drug, and a composite nanocarrier system of DE was developed to improve the drug dissolution by decreasing the drug leakage in the stomach and inhibiting the drug precipitation in the intestinal tract. With the encapsulation of drugs in nanocarriers, the precipitation percentage of DE in composite nanocarriers was 22.25 ± 3.88% in simulated intestinal fluid, which was far below that of the commercial formulation. Moreover, the relative bioavailability of DE-loaded composite nanocarriers (456.58%) was greatly enhanced and the peak of its activated partial thromboplastin time was also significantly prolonged (p < .01) compared with the commercial formulation, indicating that the anticoagulant effect of DE was effectively improved. Therefore, the designed composite nanocarrier system of DE presents great potentials in improving the therapeutic efficiency and expanding the clinical applications of poorly water-soluble weakly basic drugs.

Adherence to oral anticoagulants in patients with atrial fibrillation-a population-based retrospective cohort study linking health information systems in the Valencia region, Spain: a study protocol

INTRODUCTION

Adherence to oral anticoagulation (OAC) treatment, vitamin K antagonists or new oral anticoagulants, is an essential element for effectiveness. Information on adherence to OAC in atrial fibrillation (AF) and the impact of adherence on clinical outcomes using real-world data barely exists. We aim to describe the patterns of adherence to OAC over time in patients with AF, estimate the associated factors and their impact on clinical events, and assess the same issues with conventional measures of primary and secondary adherence-proportion of days covered (PDC) and persistence-in routine clinical practice.

METHODS AND ANALYSIS

This is a population-based retrospective cohort study including all patients with AF treated with OAC from 2010 to date in Valencia, Spain; data will be obtained from diverse electronic records of the Valencia Health Agency.

PRIMARY OUTCOME MEASURE

adherence trajectories.

SECONDARY OUTCOMES

(1) primary non-adherence; (2) secondary adherence: (a) PDC, (b) persistence. Clinical outcomes: hospitalisation for haemorrhagic or thromboembolic events and death during follow-up.

ANALYSIS

(1) description of baseline characteristics, adherence patterns (trajectory models or latent class growth analysis models) and conventional adherence measures; (2) logistic or Cox multivariate regression models, to assess the associations between adherence measures and the covariates, and logistic multinomial regression models, to identify characteristics associated with each trajectory; (3) Cox proportional hazard models, to assess the relationship between adherence and clinical outcomes, with propensity score adjustment applied to further control for potential confounders; (4) to estimate the importance of different healthcare levels in the variations of adherence, logistic or Cox multilevel regression models.

ETHICS AND DISSEMINATION

This study has been approved by the corresponding Clinical Research Ethics Committee. We plan to disseminate the project's findings through peer-reviewed publications and presentations at relevant health conferences. Policy reports will also be prepared in order to promote the translation of our findings into policy and clinical practice.

Practical management of new oral anticoagulants after total hip or total knee arthroplasty

Within the past 5 years, the oral anticoagulants rivaroxaban, apixaban, and dabigatran etexilate have been approved for the prevention of venous thromboembolism in adult patients after elective hip or knee arthroplasty in the European Union and many other countries worldwide. These agents differ from the previously available anticoagulants because they selectively and directly inhibit a single factor in the coagulation cascade-rivaroxaban and apixaban inhibit Factor Xa, and dabigatran inhibits Factor IIa (thrombin)-potentially enhancing the predictability of their anticoagulant effect. Currently, although some guidelines provide recommendations for the use of rivaroxaban, dabigatran etexilate, and apixaban in clinical practice, there are still questions regarding the optimal practical management of patients receiving these agents. This article briefly reviews the practical limitations associated with conventional anticoagulants, discusses potential issues with the practical management of the newer oral anticoagulants, and provides clinical experience from a single institution where rivaroxaban and dabigatran etexilate have been used within their approved indications.

[Compliance of patients undergoing thromboprophylaxis with enoxaparin: the COMFORT study]

Venous thromboembolism and subsequent pulmonary embolism are frequent and sometimes fatal complications in patients after surgical interventions. To prevent thromboembolisms an effective prophylaxis is necessary and outpatients in particular need adequate compliance. The aim of the prospective non-interventional study COMFORT was to analyze 8,091 outpatients after surgical and orthopedic interventions with different risk profiles with respect to factors affecting patient compliance in a positive or negative way. The follow-up period was 14 days and 92.5 % of the patients took the medication for the prescribed duration, 2.1 % (n = 166) terminated the medication too early and no information was available for 5.9 % (n = 442) of the patients. The reasons given for the premature termination of the injections were no more need for prophylaxis and end of medication by order of the physician due to mobilization or adverse events. Of the patients 73 % stated that the administartion was simple and without any problems and the majority of patients recognized injection as the administration mode of low molecular weight heparin to be the most important medication. The findings of this study can contribute to a better understanding of patient compliance.

A retrospective assessment comparing pharmacist-managed anticoagulation clinic with physician management using international normalized ratio stability

To assess the rates of therapeutic international normalized ratio (INR) levels between pharmacist-managed clinics compared to traditional physician-management and to determine the variation in rates of therapeutic INR levels between pharmacist-managed clinic data compared to physician-management. Retrospective, randomized, chart review. Referral only, outpatient, pharmacist based anticoagulation clinic under a community based tertiary care health system. Sixty-four patients with at least 1 year's worth of visits to the pharmacist managed clinic were reviewed for INR stability. The average percentage of visits within the defined therapeutic range, was 71.1% for the physician-managed group versus 81.1% for the pharmacist-managed group (P < 0.0001). The estimated variance in average therapeutic INR rates was double for the physician-managed group (365.7) versus the pharmacist-managed group (185.2) (P = 0.004). The pharmacist-managed anti-coagulation clinic had higher rates of INRs determined to be therapeutic and also exhibited significantly less variability in therapeutic INR rates relative to the physician-managed service.