Therapeutic compliance with rivaroxaban in preventing stroke in patients with non-valvular atrial fibrillation: CUMRIVAFA study

Non-traumatic extraocular muscle haemorrhage associated with anticoagulation use

We present a case of a unilateral extraocular muscle haematoma in an adult female patient who was compliant with life-long oral anticoagulation for recurrent deep vein thrombosis. The patient presented with symptoms of sudden-onset left-sided headache radiating to the temporal region, which started 2 days prior. No obvious triggering factors were identified. Cranial and ocular examinations were within normal limits. Imaging revealed a haemorrhage related to the lateral rectus muscle of the left eye. Conservative management was employed with abstinence from anticoagulation for 2 weeks and a weaning regime of oral steroids. Under the clinical review of ophthalmology and interval radiological monitoring, symptoms were reduced with reduction of haemorrhage size. Anticoagulation was reinstated after 2 weeks. To our knowledge, this is the first case of a non-traumatic extraocular muscle haematoma to be reported in a patient on anticoagulation.

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.

Outcome reporting from clinical trials of non-valvular atrial fibrillation treated with traditional Chinese medicine or Western medicine: a systematic review

OBJECTIVES

To examine variation in outcomes, outcome measurement instruments (OMIs) and measurement times in clinical trials of non-valvular atrial fibrillation (NVAF) and to identify outcomes for prioritisation in developing a core outcome set (COS) in this field.

DESIGN

This study was a systematic review.

DATA SOURCES

Clinical trials published between January 2015 and March 2019 were obtained from PubMed, the Cochrane Library, Web of Science, Wanfang Database, the China National Knowledge Infrastructure and SinoMed.

ELIGIBILITY CRITERIA

Randomised controlled trials (RCTs) and observational studies were considered. Interventions included traditional Chinese medicine and Western medicine. The required treatment duration or follow-up time was ≥4 weeks. The required sample size was ≥30 and≥50 in each group in RCTs and observational studies, respectively. We excluded trials that aimed to investigate the outcome of complications of NVAF, to assess the mechanisms or pharmacokinetics, or for which full text could not be acquired.

DATA EXTRACTION AND SYNTHESIS

The general information and outcomes, OMIs and measurement times were extracted. The methodological and outcome reporting quality were assessed. The results were analysed by descriptive analysis.

RESULTS

A total of 218 articles were included from 25 255 articles. For clinical trials of antiarrhythmic therapy, 69 outcomes from 16 outcome domains were reported, and 28 (31.82%, 28/88) outcomes were reported only once; the most frequently reported outcome was ultrasonic cardiogram. Thirty-one outcomes (44.93%, 31/69) were provided definitions or OMIs; the outcome measurement times ranged from 1 to 20 with a median of 3. For clinical trials of anticoagulation therapy, 82 outcomes from 18 outcome domains were reported; 38 (29.23%, 38/130) outcomes were reported only once. The most frequently reported outcome was ischaemic stroke. Forty (48.78%, 40/82) outcomes were provided OMIs or definitions; and the outcome measurement times ranged from 1 to 27 with a median of 8.

CONCLUSION

Outcome reporting in NVAF is inconsistent. Thus, developing a COS that can be used in clinical trials is necessary.

Differences between patient-driven adherence to vitamin K antagonists and direct oral anticoagulants. Do few missed doses matter? ACO-MEMS Study

INTRODUCTION

Lack of INR controls might affect the adherence to direct oral anticoagulants (DOAC). The vast majority of studies that addresses adherence to anticoagulants are retrospective and based on pharmacy refill data. Our aim was to compare the adherence between vitamin K antagonists (VKA) and DOAC and to analyze the clinical relevance of non-adherence.

MATERIALS AND METHODS

A prospective two-arm observational cohort study was performed in two Spanish public hospitals. Adherence was assessed by Medication Event Monitoring System. Relationship between adherence and events during follow-up and time in therapeutic range (TTR) in the VKA group were analyzed.

RESULTS

257 patients were included (132 DOAC and 125 VKA). Monitoring time was 120 days (101-133). Patients in VKA group showed higher taking adherence (97.9% vs. 95.8%) and less non-adherent patients of >5% and >10% of the doses, without differences in >20% of the doses. Taking adherence was strongly associated with TTR (AUC: 0.89, CI 95%: 0.81-0.97 of TTR for detection of non-adherent patients of >10% of doses). During a follow-up of 1.8 years (1.6-2) non-adherent patients of >5% of doses presented more thromboembolic events (HR 6.1, CI95% 1.3-28.1).

CONCLUSIONS

Although adherence to oral anticoagulant therapy was excellent, it was higher to VKA than to DOAC. Time in therapeutic range was highly sensitive to few missed doses of AVK. Non-adherence of >5% of prescribed doses had high clinical relevance.

The Role of Adherence Thresholds for Development and Performance Aspects of a Prediction Model for Direct Oral Anticoagulation Adherence

Patients who do not sufficiently adhere to their dosing regimens will, ultimately, do not get the full benefit of their medication. For example, if direct oral anticoagulants (DOAC) are not taken continuously, an intervention to improve adherence or maintain persistence will show direct effects on clinical outcomes. Usually, adherent patients are defined by taking ≥80% of their medication. The resulting binary adherence status from this threshold can as well be used for predictive classification. Thus, the threshold can determine the prediction model’s performance to identify patients at risk for poor adherence by this binary adherence status. In this perspective, we propose a plan for model development and performance considering the threshold’s role. Concerning development demands, we extracted predictors from a systematic literature search on DOAC adherence to be used as a core set of candidate predictors. Independently, we investigated how well a future model would technically have to perform by modeling drug intake and thromboembolic events based on a rivaroxaban pharmacokinetic-pharmacodynamic model. Using this simulation framework for different thresholds, we projected the impact of an imperfectly predicted adherence status on the event risk, and how imperfect sensitivity and specificity affect the cost balance if a supporting intervention was offered to patients classified as non-adherent. Our simulation results suggest applying a rather high threshold (90%) for discrimination between patients at low or high risk for non-adherence by a prediction model in order to assure cost-efficient implementation.

Factors associated with medication adherence in older patients: A systematic review

OBJECTIVE

Medication adherence is a major challenge in the treatment of older patients; however, they are under-represented in research. We undertook a systematic review focused on older patients to assess the reasons underlying non-adherence in this population.

METHODS

We searched multiple electronic databases for studies reporting reasons for non-adherence to medication regimens in patients aged 75 years and over. Our results were not limited to specific diseases, health-care settings, or geographical locations. The quality of eligible studies was assessed using the Newcastle-Ottawa Scale. A narrative synthesis of findings was performed.

RESULTS

A total of 25 publications were included, all of which were in community settings. Frequent medication review and knowledge regarding the purpose of the medication were positively associated with adherence. Factors associated with poor adherence were multimorbidity, cognitive impairment, complex regimens with multiple prescribing physicians, and problems with drug storage or formulation.

CONCLUSION

These findings suggest that interventions to improve adherence could focus on medication review aimed at simplifying regimens and educating patients about their treatment. Groups with poor adherence that may benefit most from such a model include patients with multiple comorbidities and cognitive impairment.

Secondary adherence to non-vitamin-K antagonist oral anticoagulants in patients with atrial fibrillation in Sweden and the Netherlands

OBJECTIVE

There is limited evidence on patients' adherence and the impact of the prescribed dosing regimen in non-vitamin-K oral anticoagulants (NOACs). We aimed to assess secondary adherence to NOACs and to determine the impact of the dosing regimen in patients with atrial fibrillation.

METHODS

Patients using a NOAC between 2009 and 2013 were identified from the nation-wide Swedish Prescribed Drug Register and the Dutch regional IADB.nl database. Patients using a consistent dosage for at least 180 consecutive days were included. Adherence was calculated using the medication possession ratio (MPR) and adjusted for overlapping dates. Adherence was defined as a MPR ≥0.8. Sensitivity analyses were performed using a MPR ≥0.9. Logistic regression was performed to compare secondary adherence and to explore the influence of the dosing regimen.

RESULTS

A total of 5254 Swedish and 430 Dutch NOAC users were included. The mean MPR was 96.0% (SD 7.8%) in Sweden and 95.1% (SD 10.1%) in the Netherlands. Multivariable logistic regression analysis showed that a twice daily regimen had a lower likelihood of being secondary adherent compared to a once daily regimen in Sweden (odds ratio [OR] 0.21 [95% CI 0.12-0.35]).

LIMITATIONS

The influence of selection bias introduced by the inclusion criterion of ≥2 dispensations covering at least 180 days could not be excluded.

CONCLUSIONS

This study demonstrated that secondary adherence was high in this specific setting among patients with at least two initial dispensations of a NOAC covering a minimum of 180 days. The use of NOACs in a once daily regimen showed higher adherence compared to a twice daily regimen.

Strategies for improving dabigatran adherence for stroke prevention in patients with non-valvular atrial fibrillation: education and drug intake reminders (FACILITA study)

Objective To assess the efficacy of a mixed intervention, educational, and reminder calendar of the intake, as a strategy to improve therapeutic adherence with dabigatran in patients with non-valvular atrial fibrillation (NVAF). Methods This was a prospective, longitudinal, multi-center study, carried out in 110 specialized healthcare centers in Spain. Seven hundred and twenty-six patients treated with dabigatran prescribed for stroke prevention were included. A cluster randomization was performed based on two groups: (1) Control Group (CG) as usual clinical practice, and (2) Intervention Group (IG) with a mixed strategy: (a) Healthcare education, and (b) Use of a reminder calendar for taking the anticoagulant medication. Three visits took place: baseline and follow-up at 6 and 12 months. Compliance was measured by using electronic monitors (MEMS). Average adherence percentage (%; Average AP) and daily compliance (%; Daily AP) was calculated. A patient was considered adherent when AP was 80-100%. Results Six hundred and twenty-five patients completed the study (315 in the IG and 310 in the CG). Daily AP was 91.97% at 6 months and 91.05% after 12 months in the IG and 82.26% and 82.63% in the CG. Average adherence was 90.79% and 89.20% in the IG and 64.51% and 63.22% in the CG at 6 and 12 months, respectively. Significant differences were observed in the Daily AP and Average AP, with higher percentages in the IG. In the non-adherents group, the number of concomitant drugs, baseline, and 6 months SBP values, 6 and 12 months DBP values, and weight, total cholesterol, and LDL cholesterol were significantly higher. The number needed to treat (NNT) was 3.84 patients to prevent one non-adherence. Conclusions A mixed intervention, consisting of patient education and a simple calendar reminder of drug intake, is an effective strategy to improve dabigatran therapeutic adherence in patients with NVAF. The percentage of adherence with dabigatran was high.