Health Care Resource Utilization, Costs, and Persistence in Patients Newly Diagnosed as Having Nonvalvular Atrial Fibrillation and Newly Treated With Dabigatran versus Warfarin in the United States

The association of blood urea nitrogen-to-creatinine ratio and in-hospital mortality in acute ischemic stroke patients with atrial fibrillation: data from the MIMIC-IV database

Objective

This research aimed to investigate the association between the blood urea nitrogen-to-creatinine (BUN/Cr) ratio and the rate of in-hospital mortality in patients with acute ischemic stroke (AIS) and atrial fibrillation (AF), who are also receiving care in intensive care unit (ICU).

Methods

A retrospective study was conducted using the MIMIC-IV database. We collected data on BUN/Cr levels at admission for patients with AIS and concurrent AF. To assess the association between BUN/Cr and in-hospital mortality rate, statistical analysis was conducted employing multivariable logistic regression models and restricted cubic spline models. These models were utilized to investigate the potential relationship and provide insights into the impact of BUN/Cr on the likelihood of in-hospital mortality. Interaction and subgroup analyses were performed to evaluate the consistency of the correlation.

Results

There were a total of 856 patients (age ≥ 18 years) with a median age of 78.0 years, of which 466 (54.4%) were female. Out of 856 patients, 182 (21.26%) died in the hospital. Upon controlling for confounding factors, the multivariable logistic regression analysis elucidated that patients falling within the third trisection (Q3 > 22.41 mg/dL) exhibited a noticeably increased susceptibility to in-hospital mortality when contrasted with their counterparts positioned in the second trisection (Q2: 17.2-22.41 mg/dL) (OR = 2.02, 95% CI: 1.26-3.26, p = 0.004). A non-linear J-shaped relationship was observed between BUN/Cr at ICU admission and in-hospital mortality rate (p = 0.027), with a turning point at 19.63 mg/dL. In the threshold analysis, there was a 4% rise in in-hospital mortality for each 1 mg/dL increase in BUN/Cr (OR: 1.04, 95% CI: 1.01-1.06, p = 0.012).

Conclusion

In patients with AIS complicated by AF, BUN/Cr at admission shows a J-shaped correlation with in-hospital mortality rate. When BUN/Cr exceeds 19.63 mg/dL, the in-hospital mortality rate increases.

Salvianolic acid B inhibits thrombosis and directly blocks the thrombin catalytic site

Background

Salvianolic acid B (SAB) is a major component of Salvia miltiorrhiza root (Danshen), widely used in East/Southeast Asia for centuries to treat cardiovascular diseases. Danshen depside salt, 85% of which is made up of SAB, is approved in China to treat chronic angina. Although clinical observations suggest that Danshen extracts inhibited arterial and venous thrombosis, the exact mechanism has not been adequately elucidated.

Objective

To delineate the antithrombotic mechanisms of SAB.

Methods

We applied platelet aggregation and coagulation assays, perfusion chambers, and intravital microscopy models. The inhibition kinetics and binding affinity of SAB to thrombin are measured by thrombin enzymatic assays, intrinsic fluorescence spectrophotometry, and isothermal titration calorimetry. We used molecular in silico docking models to predict the interactions of SAB with thrombin.

Results

SAB dose-dependently inhibited platelet activation and aggregation induced by thrombin. SAB also reduced platelet aggregation induced by adenosine diphosphate and collagen. SAB attenuated blood coagulation by modifying fibrin network structures and significantly decreased thrombus formation in mouse cremaster arterioles and perfusion chambers. The direct SAB-thrombin interaction was confirmed by enzymatic assays, intrinsic fluorescence spectrophotometry, and isothermal titration calorimetry. Interestingly, SAB shares key structural similarities with the trisubstituted benzimidazole class of thrombin inhibitors, such as dabigatran. Molecular docking models predicted the binding of SAB to the thrombin active site.

Conclusion

Our data established SAB as the first herb-derived direct thrombin catalytic site inhibitor, suppressing thrombosis through both thrombin-dependent and thrombin-independent pathways. Purified SAB may be a cost-effective agent for treating arterial and deep vein thrombosis.

Enablers and Hindrances of Lifestyle Changes Among Patients With Atrial Fibrillation: A Qualitative Study

BACKGROUND

Atrial fibrillation (AF) seriously affects the health status and quality of life of affected patients. However, the lifestyle changes recommended by the guidelines for patients are not ideal. Hence, understanding the factors that promote and hinder healthy behavior changes in patients with AF is crucial for self-management.

OBJECTIVE

The aims of this study were to understand the factors enabling and hindering health behaviors in patients with AF and to provide a reference for promoting health management among these patients.

METHODS

Using the purposive sampling method, 22 patients with AF admitted to the Cardiac Center of Beijing Chaoyang Hospital, Capital Medical University, from March 2021 to June 2021 were selected for in-depth face-to-face interviews. The thematic analysis method was used to summarize and refine the themes.

RESULTS

The following 2 themes and 15 subthemes were eventually extracted by analyzing and summarizing the interview data. The 7 factors facilitating health behaviors in patients with AF were risk perception, outcome expectancy, behavioral intention, action plan, response plan, self-efficacy, and social support. There were 8 hindering factors: personal preferences and habits, specific customary culture, weak self-control, accessibility of exercise conditions, symptom-related distress, cognitive weakness, multiple medication use, and insufficient awareness of condition monitoring.

CONCLUSIONS

The factors affecting health behaviors in patients with AF are complex, and healthcare providers should reinforce the facilitators of health behaviors in these patients and provide them with targeted interventions against hindering factors. Results can be used to develop health behavior intervention programs for patients with AF.

Non-persistence to Oral Anticoagulation Treatment in Patients with Non-valvular Atrial Fibrillation in the USA

BACKGROUND

Studies have shown that patients with non-valvular atrial fibrillation (NVAF) who discontinue oral anticoagulants (OACs) are at higher risk of complications such as stroke.

OBJECTIVE

This analysis compared the risk of non-persistence with OACs among patients with NVAF.

METHODS

Adult patients with NVAF who initiated apixaban, dabigatran, rivaroxaban, or warfarin were identified using 01JAN2013-30JUN2019 data from Centers for Medicare and Medicaid Services and four US commercial claims databases. Non-persistence was defined as discontinuation (no evidence of index OAC use for ≥ 60 days from the last days' supply) or switch to another OAC. Kaplan-Meier curves were generated to illustrate time to non-persistence along with cumulative incidences of non-persistence. Baseline and time-varying covariates were evaluated, and adjusted Cox proportional hazards models were used to evaluate non-persistence risk.

RESULTS

In total, 363,823 patients receiving apixaban, 57,121 receiving dabigatran, 282,831 receiving rivaroxaban, and 317,337 receiving warfarin were included. Of these, 47-72% discontinued/switched OAC therapy within an average 9-month follow-up. Apixaban was associated with a lower risk of non-persistence than were dabigatran (hazard ratio [HR] 0.62; 95% confidence interval [CI] 0.61-0.62), rivaroxaban (HR 0.76; 95% CI 0.75-0.76), and warfarin (HR 0.74; 95% CI 0.74-0.75). Dabigatran was associated with a higher risk of non-persistence than were warfarin (HR 1.21; 95% CI 1.19-1.22) and rivaroxaban (HR 1.23; 95% CI 1.22-1.25), and rivaroxaban was associated with a lower risk of non-persistence than was warfarin (HR 0.98; 95% CI 0.97-0.98). Clinical events (stroke/systemic embolism and major bleeding [MB]) during follow-up were predictors of non-persistence (stroke HR 1.57; 95% CI 1.53-1.61; MB HR 2.96; 95% CI 2.92-3.00).

CONCLUSION

In over one million patients with NVAF, our results suggest differences in anticoagulation treatment persistence across OAC agents, even after accounting for clinical events after OAC initiation. It is important for clinicians and patients to take these differences into consideration, especially as non-persistence to OAC therapy is associated with thromboembolic complications.

Real-world persistence to direct oral anticoagulants in patients with atrial fibrillation: a systematic review and network meta-analysis

OBJECTIVE

To conduct a systematic review and network meta-analysis of real-world evidence comparing adherence, persistence, cost, and utilization between oral anticoagulant (OAC) in non-valvular atrial fibrillation (NVAF) patients.

METHODS

A systematic search of MEDLINE and Embase (inception-July 2019) was conducted for published observational cohort studies comparing outcomes between ≥2 OACs. A network meta-analysis was performed to estimate odds ratios for non-persistence using a random-effects model.

RESULTS

There were 80 studies evaluating the outcomes of interest. However, due to a paucity in adherence studies and heterogeneity in adherence, cost, and utilization definitions, persistence was the focus of this network meta-analysis. There were 36 studies evaluating non-persistence in 395,593 participants, 24 of which used 3 gap definitions (30-, 60-, and 90-days); 18 unique studies evaluating non-persistence at 12 months were included in the network meta-analysis. Using 30- and 90-day gaps, all NOACs, when compared with VKAs, had lower odds of non-persistence (30-day OR (95%CI): apixaban: 0.63 (0.58, 0.69); rivaroxaban: 0.69 (0.62, 0.76); dabigatran: 0.89 (0.82, 0.97); 90-day OR (95%CI): apixaban: 0.33 (0.22, 0.47); rivaroxaban: 0.47 (0.36, 0.61); dabigatran 0.61 (0.44, 0.85)). When using a 60-day gap, dabigatran had higher odds of non-persistence vs VKAs (OR: 1.35; 95%CI: 1.12, 1.61), but there were no significant differences for apixaban and rivaroxaban. Apixaban had the lowest probability of non-persistence across the 3-gap definitions (95.7% with 30-day gap, 76.9% with 60-day gap, 98.4% with 90-day gap).

CONCLUSIONS

The current findings, despite multiple limitations, can raise awareness and understanding of real-world persistence associated with OAC therapy in NVAF patients.

Comparing stroke prevention therapy of direct oral anticoagulants and vitamin K antagonists in patients with atrial fibrillation: a nationwide retrospective observational study

BACKGROUND

Direct oral anticoagulants (DOACs) are not only increasingly being used for the initial stroke prevention therapy but progressively also substitute vitamin K antagonist (VKA) treatment in patients with non-valvular atrial fibrillation (AF). DOACs have been compared regarding therapeutic efficacy and adverse outcomes to warfarin in several pivotal studies and showed non-inferiority in terms of stroke prevention and superiority in terms of bleeding complications. However, comprehensive comparative studies are lacking for phenprocoumon, a VKA prescribed frequently outside the USA and the UK and accounting for 99% of all VKA prescriptions in Germany. Patients treated with phenprocoumon seem to meet more often international normalized ratio values in the therapeutic range, which may have implications concerning their efficacy and safety. This study aims at comparing the risk of stroke and bleeding in phenprocoumon- and DOAC-treated patients with AF in an adequately powered observational study population.

METHODS

Retrospective analysis of stroke and bleeding incidence of 837,430 patients (1.27 million patient years) treated with DOAC or phenprocoumon for stroke prevention in German ambulatory care between 2010 and 2017. Relative risks of stroke and bleeding were estimated by calculating cox regression-derived hazard ratios (HR) and 95% confidence intervals (CI) of propensity score-matched cohorts.

RESULTS

Patients treated with DOAC had an overall higher risk for stroke (HR 1.32; CI 1.29-1.35) and a lower risk for bleeding (0.89; 0.88-0.90) compared to phenprocoumon. When analyzed separately, the risk for stroke was higher for dabigatran (1.93; 1.82-2.03), apixaban (1.52; 1.46-1.58), and rivaroxaban (1.13; 1.10-1.17) but not for edoxaban (0.88; 0.74-1.05). The risk for bleeding was lower for dabigatran (0.85; 0.83-0.88), apixaban (0.71; 0.70-0.73), and edoxaban (0.29; 0.17-0.51) but not for rivaroxaban (1.03; 1.01-1.04).

CONCLUSIONS

This study provides a comprehensive view of the stroke and bleeding risks associated with phenprocoumon and DOAC use in Germany. Phenprocoumon may be preferable to DOAC treatment for the prevention of strokes in AF in a real-world population cared for in ambulatory care.

Real-World Adherence and Persistence to Direct Oral Anticoagulants in Patients With Atrial Fibrillation: A Systematic Review and Meta-Analysis

BACKGROUND

Stroke reduction with direct oral anticoagulants (DOACs) in atrial fibrillation (AF) is dependent on adherence and persistence in the real-world setting. Individual study estimates of DOAC adherence/persistence rates have been discordant. Our aims were to characterize real-world observational evidence for DOAC adherence/persistence and evaluate associated clinical outcomes in patients with AF.

METHODS AND RESULTS

PubMed, EMBASE, and CINAHL were searched from inception to June 2018. Observational studies that reported real-world DOAC adherence/persistence in patients with AF were included. Study quality was assessed using the Newcastle-Ottawa Scale. Meta-analyses for pooled estimates were performed using DerSimonian and Laird random-effects models. Outcomes included DOAC mean proportion of days covered or medication possession ratio, proportion of good adherence (proportion of days covered/medication possession ratio ≥80%), persistence, DOAC versus vitamin K antagonists persistence, and clinical outcomes associated with nonadherence/nonpersistence. Forty-eight observational studies with 594 784 unique patients with AF (59% male; mean age 71 years) were included. The overall pooled mean proportion of days covered/medication possession ratio was 77% (95% CI, 75%-80%), proportion of patients with good adherence was 66% (95% CI, 63%-70%), and proportion persistent was 69% (95% CI, 65%-72%). The pooled proportion of patients with good adherence was 71% (95% CI, 64%-78%) for apixaban, 60% (95% CI, 52%-68%) for dabigatran, and 70% (95% CI, 64%-75%) for rivaroxaban. Similar patterns were found for pooled persistence by agent. The pooled persistence was higher with DOACs than vitamin K antagonists (odds ratio, 1.44 [95% CI, 1.12-.86]). DOAC nonadherence was associated with an increased risk of stroke (hazard ratio, 1.39 [95% CI, 1.06-1.81]).

CONCLUSIONS

Suboptimal adherence and persistence to DOACs was common in patients with AF, with 1 in 3 patients adhering to their DOAC <80% of the time, which was associated with poor clinical outcomes in nonadherent patients. Although it is convenient that DOACs do not require laboratory monitoring, greater effort in monitoring for and interventions to prevent nonadherence may be necessary to optimize stroke prevention. Increased clinician awareness of DOAC nonadherence may help identify at-risk patients.

Persistence of oral anticoagulant treatment for atrial fibrillation in the Netherlands: A surveillance study

BACKGROUND

In contrast to vitamin K antagonists (VKA), direct oral anticoagulants (DOAC's) are not strictly monitored and dose titrated by anticoagulation clinics in the Netherlands. This may affect drug persistence of atrial fibrillation (AF) patients, whom often require lifelong treatment.

OBJECTIVES

To assess persistence of DOACs and of VKAs in patients with AF.

METHODS

Dispensing data from the Dutch Foundation of Pharmaceutical Statistics were used to monitor persistence of AF patients to DOAC from 1 January 2012-1 April 2016. In addition, we estimated the persistence of AF patients to VKA between 1 January 2004 and 1 January 2012 in data from the Anticoagulation Clinic Leiden. Non-persistence was defined as the cumulative incidence of patients who completely stopped DOAC, switched to another oral anticoagulant or stopped their VKA.

RESULTS

DOAC users (n = 77 333) were younger than VKA users (n = 10 079; 70 vs 73 years). Non-Persistence to DOAC (ie stopping with any oral anticoagulant) was 34% at 1 and 64% at 4 years, compared to 22% at one and 36% at 4 years for VKA. Approximately a Twenty-five percent of those who had stopped their initial DOAC switched to another anticoagulant (VKA or another DOAC). Multivariable analyses revealed that young age, female sex, no concomitant drug use and non-adherence were predictors for non-persistence of DOAC.

CONCLUSIONS

Persistence to DOAC was low and in line with other observational studies, and higher for VKA. Our results show a clear correlation between age <60 years and worse persistence, as well as with female and non-adherence to DOAC.

Healthcare resource utilization and expenditures among newly-diagnosed elderly non-valvular atrial fibrillation patients initiating oral anticoagulants

Aims: Non-valvular atrial fibrillation (NVAF) prevalence increases with age. Hence, evaluating the economic burden among older-aged patients is vital. This study aimed to compare healthcare resource utilization (HRU) and costs among newly-diagnosed older-aged NVAF patients treated with warfarin, rivaroxaban, or apixaban vs. dabigatran.Materials and Methods: Newly-diagnosed older-aged (aged ≥65 years) NVAF patients initiating dabigatran, warfarin, rivaroxaban, or apixaban (first prescription date = index date) from 01JAN2010-31DEC2015 and with continuous enrollment for ≥12 months pre-index date were included from 100% Medicare database. Patient data were assessed until drug discontinuation/switch/dose change/death/disenrollment/study end (up to 12 months). Dabigatran initiators were 1:1 propensity score-matched (PSM) with warfarin, rivaroxaban, or apixaban initiators. Generalized linear models were used to compare all-cause HRU and costs per-patient-per-month (PPPM) between the matched cohorts.Results: After PSM with dabigatran, 70,531 warfarin, 51,673 rivaroxaban, and 25,209 apixaban patients were identified. Dabigatran patients had significantly fewer generalized-linear-model-adjusted PPPM hospitalizations (0.114 vs. 0.123; 0.111 vs. 0.121), and outpatient visits (2.864 vs. 4.201; 2.839 vs. 2.949) than warfarin and rivaroxaban patients, respectively, but had significantly more PPPM hospitalizations (0.103 vs. 0.090) and outpatient visits (2.780 vs. 2.673) than apixaban patients (all p < .0001). Dabigatran patients incurred significantly lower adjusted total PPPM costs ($3,309 vs. $3,362; $3,285 vs. $3,474) than warfarin and rivaroxaban patients, respectively (all p < .01) but higher total PPPM costs ($3,192 vs. $2,986) than apixaban patients (all p < .0001).Limitations: This study is subject to the inherent limitations of any claims dataset, including potential bias from coding errors and identification of medical conditions using diagnosis codes as opposed to clinical evidence. Medications filled over-the-counter or provided as samples by the physician are never captured in claims data.Conclusions: Newly-diagnosed older-aged NVAF patients initiating dabigatran incurred significantly lower adjusted all-cause HRU and costs than warfarin and rivaroxaban patients but higher adjusted HRU and costs than apixaban patients.

Healthcare Utilization and Expenditures in Working-Age Adults with Atrial Fibrillation: The Effect of Switching from Warfarin to Non-Vitamin K Oral Anticoagulants

OBJECTIVE

Our objective was to evaluate the association between switching from warfarin to non-vitamin K oral anticoagulants (NOACs) and potential drug-drug interactions (DDIs), healthcare utilization, and expenditures in working-age adults with atrial fibrillation (AF).

METHODS

We conducted a retrospective cohort study using data from 2010 to 2015 for patients who switched from warfarin to NOACs (switchers) and those who continued to receive warfarin (non-switchers). We identified medications known or suspected to have clinically significant interactions with NOACs or warfarin. We used multivariate logistic regression, negative binomial, and generalized linear models to evaluate the influence of switching to NOACs and of potential DDIs on inpatient visits, outpatient visits, number of outpatient visits, and non-drug medical expenditures. Inverse probability of treatment weighting was also applied in analyses.

RESULTS

A total of 4126 patients with AF were included in the study. Switching to NOACs was significantly and negatively related to the number of outpatient, inpatient, and emergency room (ER) visits and non-drug medical expenditures. When potential DDIs were included in the models, switching remained significantly associated only with reduced inpatient and outpatient visits. Notably, having at least one potential DDI was associated with an increased likelihood of ER visits and the number of outpatient visits; it was also significantly and positively associated with non-drug medical expenditures.

CONCLUSIONS

Relative to persistent warfarin use, switching to NOACs was associated with fewer inpatient, ER, and outpatient visits and lower non-drug costs. Potential DDIs were also strongly and positively associated with healthcare utilization and expenditures. Both are critical to consider in the management of AF in working-age adults.

Factors influencing dabigatran or warfarin medication persistence in patients with nonvalvular atrial fibrillation

Factors influencing differences in persistence between dabigatran and warfarin in patients with nonvalvular atrial fibrillation (NVAF) remain unclear. Aim: Compare differences in persistence between new dabigatran and warfarin users in patients newly diagnosed with NVAF, adjusting for sociodemographics, clinical characteristics, patient out-of-pocket cost and other covariates. Methods: A retrospective matched-cohort study was conducted using a US claims database of Medicare and commercially insured patients with NVAF aged≥ 18 years. Persistence and monthly out-of-pocket costs for dabigatran or warfarin were calculated and adjusted for covariates using Cox proportional hazard models. Results & conclusion: Unadjusted persistence was significantly lower among dabigatran users (n = 1025) compared with matched warfarin users (38 vs 46%). Adjusting for covariates rendered this difference insignificant (hazard ratio = 0.930).

Real-world effectiveness and safety of oral anticoagulation strategies in atrial fibrillation: a cohort study based on a German claims dataset

Objective

To compare the real-world effectiveness and safety of non-vitamin-K-antagonist oral anticoagulant (NOAC) treatment in atrial fibrillation (AF) patients with a vitamin-K-antagonist (VKA)-based treatment.

Methods

This was a retrospective analysis of an anonymized claims dataset from 3 German health insurance funds covering the period from January 01, 2010 to June 30, 2014, with a minimum observation time of 12 months. All continuously insured patients with at least 2 outpatient AF diagnoses and/or 1 inpatient respective diagnosis who received at least 1 outpatient prescription of a NOAC or VKA were included.

Outcomes and measures

Death, ischemic strokes (IS), non-specified strokes, transient ischemic attacks (TIAs), myocardial infarctions (MIs), arterial embolism (AE), hemorrhagic strokes, severe bleedings, and composite outcomes. Main comparisons were done based on propensity score-matched (PSM) cohorts. Results were reported as incidence rate ratios and hazard ratios (HRs).

Results

We assigned 37,439 AF patients to each PSM cohort (NOAC cohort: mean age 78.2 years, mean CHA₂DS₂VASc score 2.96, mean follow-up 348.5 days; VKA cohort: mean age 78.2 years, mean CHA₂DS₂VASc 2.95, mean follow-up 365.5 days). NOAC exposure was associated with significantly higher incidence rate ratios; 95% CI/HRs; 95% CI for the following outcomes: death (1.22; 1.17–1.28/1.22; 1.17–1.28), IS (1.90; 1.69–2.15/1.92; 1.69–2.19), non-specified strokes (2.04; 1.16–3.70/1.93; 1.13–3.32), TIAs (1.52; 1.29–1.79/1.44; 1.21–1.70), MIs (1.26; 1.10–1.15/1.31; 1.13–1.52), AE (1.75; 1.32–2.32/1.81; 1.36–2.34) and severe bleeding (1.92; 1.71–2.15/1.95; 1.74–2.20). Multivariable Cox regression analyses and additional sensitivity analysis, including analysis of PSM-matched NOAC/VKA treatment-naive patients, only confirmed the above results. The study was documented under clinicaltrials.gov (NCT02657616).

Conclusion and relevance

A VKA therapy seems to be more effective and safer than a NOAC therapy in a real-world cohort of German AF patients.

Real-World Health Care Costs Based on Medication Adherence and Risk of Stroke and Bleeding in Patients Treated with Novel Anticoagulant Therapy

BACKGROUND

With the lack of real-world evidence, the challenge for drug reimbursement policy decision makers is to understand medication adherence behavior among users of novel oral anticoagulants (NOACs) and its effect on overall cost savings. No study has examined and quantified the burden of cost in high-risk patients taking NOAC therapy.

OBJECTIVE

To examine the association of cost with adherence, comorbidity, and risk of stroke and bleeding in patients taking NOACs (rivaroxaban and dabigatran).

METHODS

A retrospective cohort study used deidentified data from a commercial managed care database affiliated with Optum Clinformatics Data Mart (January 1, 2010-December 31, 2012). Patients aged 18 years and older with ≥ 1 diagnosis of atrial fibrillation/flutter, > 1 NOAC prescription, 6-month pre-index and 12-month post-index continuous enrollment, and CHA₂DS₂-VASc score ≥ 1 were included. Adherence was calculated using proportion of days covered (PDC ≥ 80%) over an assessment period of 3, 6, and 12 months and compared based on level of comorbidity, stroke, and bleeding risk. The adjusted annual health care costs per patient (drug, medical, and total) were calculated using multivariable gamma regression controlling for demographic and clinical characteristics and compared across groups based on adherence over 12 months, baseline level of comorbidity, and risk of stroke and bleeding.

RESULTS

Of 25,120 NOAC patients, 2,981 patients were included in the final cohort. Based on a PDC threshold of ≥ 80%, the adherence rate over 3, 6, and 12 months was 72%, 65%, and 54%, respectively. For all time periods, the level of adherence significantly increased (P < 0.001), with an increase in stroke risk (based on CHA₂DS₂VASc scores of 1, 2-3, and 4+); comorbidity (Charlson Comorbidity Index scores of 0, 1-2, and 3+); and risk of bleeding (HAS-BLED scores of 0-1, 2, and 3+). Adjusted all-cause total cost calculated for a 12-month period was significantly lower ($29,742 vs. $33,609) among adherent versus nonadherent users. Drug cost was higher ($5,595 vs. $2,233) among adherent versus nonadherent patients but was offset by lower medical costs ($23,544 vs. $30,485) costs. The overall cost significantly increased for patients with a high risk of bleeding and a high level of comorbidity.

CONCLUSIONS

Adherence to NOAC therapy led to a reduction in overall health care cost, since higher drug costs were offset by lower medical (inpatient and outpatient) costs among adherent patients. Cost information based on adherence and risk of stroke and bleeding can help formulary decision makers to assess risk-benefit and help clinicians in developing interventions to reduce patient burden.

DISCLOSURES

Funding to acquire the data source was provided by the University of Rhode Island College of Pharmacy, Kingston, to support PhD dissertation work. Deshpande is currently an employee of Pharmerit International.

Evaluating the Usability and Usefulness of a Mobile App for Atrial Fibrillation Using Qualitative Methods: Exploratory Pilot Study

BACKGROUND

Atrial fibrillation (AFib) is the most common form of heart arrhythmia and a potent risk factor for stroke. Nonvitamin K antagonist oral anticoagulants (NOACs) are routinely prescribed to manage AFib stroke risk; however, nonadherence to treatment is a concern. Additional tools that support self-care and medication adherence may benefit patients with AFib.

OBJECTIVE

The aim of this study was to evaluate the perceived usability and usefulness of a mobile app designed to support self-care and treatment adherence for AFib patients who are prescribed NOACs.

METHODS

A mobile app to support AFib patients was previously developed based on early stage interview and usability test data from clinicians and patients. An exploratory pilot study consisting of naturalistic app use, surveys, and semistructured interviews was then conducted to examine patients' perceptions and everyday use of the app.

RESULTS

A total of 12 individuals with an existing diagnosis of nonvalvular AFib completed the 4-week study. The average age of participants was 59 years. All participants somewhat or strongly agreed that the app was easy to use, and 92% (11/12) reported being satisfied or very satisfied with the app. Participant feedback identified changes that may improve app usability and usefulness for patients with AFib. Areas of usability improvement were organized by three themes: app navigation, clarity of app instructions and design intent, and software bugs. Perceptions of app usefulness were grouped by three key variables: core needs of the patient segment, patient workflow while managing AFib, and the app's ability to support the patient's evolving needs.

CONCLUSIONS

The results of this study suggest that mobile tools that target self-care and treatment adherence may be helpful to AFib patients, particularly those who are newly diagnosed. Additionally, participant feedback provided insight into the varied needs and health experiences of AFib patients, which may improve the design and targeting of the intervention. Pilot studies that qualitatively examine patient perceptions of usability and usefulness are a valuable and often underutilized method for assessing the real-world acceptability of an intervention. Additional research evaluating the AFib Connect mobile app over a longer period, and including a larger, more diverse sample of AFib patients, will be helpful for understanding whether the app is perceived more broadly to be useful and effective in supporting patient self-care and medication adherence.

Comparison of all-cause costs and healthcare resource use among patients with newly-diagnosed non-valvular atrial fibrillation newly treated with oral anticoagulants

OBJECTIVES

Compare costs and healthcare resource utilization (HCRU) among newly-diagnosed non-valvular atrial fibrillation (NVAF) patients newly treated with dabigatran vs apixaban, rivaroxaban, or warfarin.

METHODS

Newly-diagnosed adult NVAF patients initiating dabigatran, apixaban, rivaroxaban, or warfarin (index event) between October 1, 2010-December 31, 2014 were identified using MarketScan claims data, and followed until medication discontinuation, switch, inpatient death, enrollment end, or study end (December 31, 2015). Dabigatran patients were propensity-score matched 1:1 separately with apixaban, rivaroxaban, and warfarin patients. Per-patient-per-month (PPPM) all-cause cost, HCRU, and 30-day re-admissions were reported. Costs were analyzed using generalized linear models.

RESULTS

Final cohorts, each matched with dabigatran patients, included 8,857 apixaban patients, 26,592 rivaroxaban patients, and 33,046 warfarin patients. Dabigatran patients had lower adjusted PPPM total healthcare, inpatient, and outpatient costs compared to rivaroxaban ($4,093 vs $4,636, $1,476 vs $1,862, and $2,016 vs $2,121, respectively, all p ≤ .001) and warfarin ($4,199 vs $4,872, $1,505 vs $1,851, and $2,049 vs $2,514, respectively, all p < .001). Adjusted costs were similar for dabigatran and apixaban. Dabigatran patients had significantly fewer hospitalizations, outpatient visits, and pharmacy claims than rivaroxaban patients (0.06 vs 0.07, 4.84 vs 4.96 and 4.80 vs 4.93, respectively, all p < .020) and warfarin patients (0.06 vs 0.07, 4.77 vs 6.88, and 4.76 vs 5.89, respectively, all p < .001). Dabigatran patients had similar hospitalizations to apixaban, but higher outpatient visits (4.70 vs 4.31) and pharmacy claims (4.86 vs 4.61), both p < .001.

CONCLUSIONS

This real-world study found adjusted all-cause costs were lower for dabigatran compared to rivaroxaban and warfarin patients and similar to apixaban patients.

Health Care Resource Utilization and Costs Among Newly Diagnosed and Oral Anticoagulant-Naive Nonvalvular Atrial Fibrillation Patients Treated with Dabigatran or Warfarin in the United States

BACKGROUND

Warfarin has a long history of use to reduce the risk of stroke in patients with atrial fibrillation (AF), but it requires frequent laboratory monitoring to maintain international normalized ratio levels in the therapeutic range. Dabigatran, a novel oral anticoagulant (OAC), has demonstrated efficacy in reducing the risk of stroke and systemic embolism and does not require laboratory monitoring.

OBJECTIVE

To compare health care resource utilization (HCRU) and costs of OAC-naive patients newly diagnosed with nonvalvular atrial fibrillation (NVAF), using dabigatran or warfarin.

METHODS

This retrospective observational study used data from medical and pharmacy claims extracted from the HealthCore Integrated Research Database representing commercial and Medicare Advantage members. Adults aged > 18 years with a medical diagnosis claim of NVAF were identified between October 1, 2010, and December 31, 2011. The date of first observed OAC prescription claim was the index date. Patients were followed for up to 12 months after the index date. Patients were assigned to the dabigatran or warfarin treatment groups based on their first OAC prescription fills. To reduce potential for selection bias, the cohorts were matched on baseline characteristics using propensity score matching. HCRU was measured and compared between groups on a per-patient-per-month (PPPM) basis for all-cause HCRU, as well as stroke, myocardial infarction, and bleed-specific HCRU. Pharmacy, medical, and total costs were also compared and adjusted to 2012 U.S. dollars. Generalized linear models were conducted to compare all-cause health care costs between cohorts.

RESULTS

After propensity score matching, 1,648 patients were included in the analysis (824 each in the dabigatran and warfarin treatment groups). In the post-index period, patients in the dabigatran group had significantly fewer all-cause PPPM physician office visits (mean [SD] 1.29 [± 0.95] vs. 2.02 [± 1.53], P < 0.001) and outpatient visits (mean [SD] 2.17 [± 2.90] vs. 3.52 [± 3.32], P < 0.001) compared with those in the warfarin group. There were no between-group differences in outcomes for the number of stroke, myocardial infarction, or bleeding-related office visits. All-cause medical costs for the dabigatran cohort were lower than the warfarin cohort; however, the difference did not reach statistical significance ($2,696 [SD ± $6,699] vs. $2,893 [± $6,819], P = 0.179). All-cause pharmacy costs were higher in the dabigatran group versus the warfarin group ($455 [± $429] vs. $328 [± $517], P < 0.001). The dabigatran cohort also had significantly higher stroke-related ($32 [± $71] vs. $20 [± $55], P = 0.006) and nonstroke-related pharmacy costs ($423 [± $422] vs. $308 [± $515], P < 0.001). Despite higher pharmacy costs for the dabigatran cohort, both treatment groups had statistically similar all-cause total costs ($3,151 [± $6,744] vs. $3,221 [± $6,869], P = 0.701).

CONCLUSIONS

This real-world study showed that among patients newly diagnosed with NVAF who were OAC naive, dabigatran use was associated with significantly less HCRU in terms of physician and outpatient visits but higher pharmaceutical costs in up to 12 months of follow-up. Similar to other real-world studies, this research supports the finding that higher pharmacy costs for dabigatran users was offset by lower medical costs, making total health care costs comparable between dabigatran and warfarin.

DISCLOSURES

This work was supported by Boehringer Ingelheim Pharmaceuticals, which is the manufacturer of dabigatran, one of the products included in the analysis of this work. The authors were responsible for all content and editorial decisions. Jain and Tan are employed by HealthCore, a research consultancy which was funded by Boehringer Ingelheim Pharmaceuticals for work on this study. Fu was employed by HealthCore at the time of this study. Lim, Wang, Elder, and Sander are employees of Boehringer Ingelheim Pharmaceuticals. Study concept and design were contributed by Wang, Sander, and Tan, along with Fu and Jain. Fu, Tan, and Jain collected the data, and data interpretation was performed by Lim, Wang, and Sander, along with Jain, Tan, and Fu. The manuscript was written by Jain, Elder, Tan, and Wang, along with Lim and Fu, and revised by Jain, Wang, Elder, and Tan. Some of the results of this study were presented at Quality of Care and Outcomes Research in Cardiovascular Disease and Stroke (QCOR) 2014 Scientific Sessions on June 2-4, 2014, in Baltimore, Maryland.

Predictors for total hospital and cardiology cost claims among patients with atrial fibrillation initiating dabigatran or acenocoumarol in The Netherlands

AIMS

The prevalence of atrial fibrillation (AF) has increased over the past years due to aging of the population, and healthcare costs associated with AF reflect a significant financial burden. The aim of this study was to explore predictors for the real-world AF-related in-hospital costs in patients that recently initiated anticoagulation with acenocoumarol or dabigatran.

METHODS

Predictors for claimed total hospital care costs and cardiology costs in AF patients were explored by using hospital financial claims data from propensity score matched patient groups in a large Dutch community hospital. This study analyzed the total dataset (n = 766) and carried out a secondary analysis for all matched pairs of anticoagulation naïve AF patients (n = 590) by ordinal regression.

RESULTS

Dabigatran was a predictor for significantly lower cardiology and total hospital care costs (Odds Ratio [OR] = 0.43, 95% confidence interval (CI) = 0.33-0.57; and OR = 0.60, 95% CI = 0.46-0.79, respectively). Female gender was a predictor for lower total hospital care costs. Predictors for an increase in total hospital care costs were the occurrence of stroke or systemic embolism, major bleeding, and minor bleeding. The costs predictors were comparable when limiting the analysis to patients that were anticoagulation naïve. Age and CHA₂DS₂-VASc were not predictors for either cardiology or total hospital care costs in both analyses.

CONCLUSION

Dabigatran treatment was as a predictor for lower cardiology costs and lower total hospital care costs in AF patients that initiated oral anticoagulation.

All-Cause, Stroke-, and Bleed-Specific Healthcare Costs: Comparison among Patients with Non-Valvular Atrial Fibrillation (NVAF) Newly Treated with Dabigatran or Warfarin

OBJECTIVE

Our objective was to compare all-cause and stroke- and bleed-specific healthcare costs among patients with non-valvular atrial fibrillation (NVAF) treated with dabigatran or warfarin.

METHODS

Administrative claims data from the MarketScan® Databases for 2009-2014 were used. Patients with NVAF newly treated with dabigatran were matched 1:1 to those treated with warfarin. All-cause and stroke- and bleed-specific costs per patient per month (PPPM) ($US, year 2015 values) up to a 12-month follow-up period were analyzed. Stroke- or bleed-specific costs were defined as hospitalizations with stroke or bleed as the primary discharge diagnosis and outpatient claims with stroke or bleed diagnosis in any position. Differences in costs between dabigatran and warfarin users were assessed using descriptive and multivariate analyses.

RESULTS

A total of 18,980 dabigatran-treated patients were matched to corresponding warfarin-treated patients. Adjusted all-cause total healthcare, inpatient, and outpatient costs were significantly lower for the dabigatran cohort ($US3053 vs. 3433; $US904 vs. 1194; $US1594 vs. 1894, respectively; all p < 0.001), but mean pharmacy costs were significantly higher ($US556 vs. 345, p < 0.001). Stroke-specific total healthcare and outpatient costs were significantly lower for the dabigatran than for the warfarin cohort ($US30.37 vs. 40.99 and $US7.36 vs. 12.20, respectively; p < 0.05 for both values). Similarly, bleed-specific total healthcare and inpatient costs were significantly lower for the dabigatran than for the warfarin cohort ($US50.00 vs. 73.49 and $US27.75 vs. 48.66, respectively; p < 0.01 for both values).

CONCLUSION

Patients receiving dabigatran had significantly lower total all-cause, inpatient, and outpatient costs but higher pharmacy costs than those receiving warfarin. In addition, stroke-specific total and outpatient costs and bleed-specific total and inpatient costs were significantly lower in dabigatran users compared with warfarin users.

Oral anticoagulant persistence in patients with non-valvular atrial fibrillation: A cohort study using primary care data in Germany

This study examined characteristics and treatment persistence among patients prescribed oral anticoagulants (OACs) for stroke prevention in non-valvular atrial fibrillation (NVAF). We identified 15,244 patients (51.8% male, 72.7% aged ≥70) with NVAF and no prior OAC therapy who were prescribed apixaban (n = 1,303), rivaroxaban (n = 5,742), dabigatran (n = 1,622) or vitamin-K antagonists (VKAs, n = 6,577) between 1-Dec-2012 and 31-Oct-2014 in German primary care (IMS® Disease Analyzer). We compared OAC persistence using Cox regression over patients’ entire follow-up and using a data-driven time-partitioned approach (before/after 100 days) to handle non-proportional hazards. History of stroke risk factors (stroke/transient ischaemic attack [TIA] 15.2%; thromboembolism 14.1%; hypertension 84.3%) and high bleeding risk (HAS-BLED score≥3 68.4%) was common. Apixaban-prescribed patients had more frequent history of stroke/TIA (19.7%) and high bleeding risk (72.6%) than other OACs. 12-month persistence rates were: VKA 57.5% (95% confidence interval (CI) 56.0–59.0%), rivaroxaban 56.6% (54.9–58.2%), dabigatran 50.1% (47.2–53.1%), apixaban 62.9% (58.8–67.0%). Over entire follow-up, compared to VKA, non-persistence was similar with apixaban (adjusted hazard ratio 1.08, 95% CI 0.95–1.24) but higher with rivaroxaban (1.21, 1.14–1.29) and dabigatran (1.53, 1.40–1.68). Using post-hoc time-partitioned approach: in first 100 days, non-persistence was higher with apixaban (1.37, 1.17–1.59), rivaroxaban (1.41, 1.30–1.53) and dabigatran (1.91, 1.70–2.14) compared to VKA. Compared to apixaban, rivaroxaban non-persistence was similar (1.03, 0.89–1.20), dabigatran was higher (1.39, 1.17–1.66). After 100 days, apixaban non-persistence was lower than VKA (0.66, 0.52–0.85); rivaroxaban (0.97, 0.87–1.07) and dabigatran (1.10, 0.95–1.28) were similar to VKA. Furthermore, rivaroxaban (1.46, 1.13–1.88) and dabigatran (1.67, 1.26–2.19) non-persistence was higher than apixaban. This study describes real-world observations on OAC use, particularly early apixaban use following approval for NVAF, in Germany. We identified potential differential OAC prescribing and higher persistence with apixaban than other OACs after 100 days’ treatment. Larger studies are needed with longer follow-up to establish long-term patterns.

Once- versus twice-daily direct oral anticoagulants in non-valvular atrial fibrillation

INTRODUCTION

Direct oral anticoagulants (DOACs) have emerged as alternatives to vitamin K antagonists for the prevention of stroke in patients with non-valvular atrial fibrillation (NVAF). Four DOACs: dabigatran, rivaroxaban, apixaban and edoxaban, are currently available. In the absence of head-to-head clinical comparisons of DOACs, dosing regimen may influence drug choice. Areas covered: Edoxaban and rivaroxaban are administered once daily, dabigatran and apixaban twice daily. The selection of these dosage regimens is largely based on studies for the prevention or treatment of venous thromboembolism or acute coronary syndrome. Edoxaban is the only DOAC in which once and twice-daily regimens were compared in patients with NVAF; bleeding rates were higher in the twice-daily groups. Once-daily versus twice-daily regimens have a number of practical implications. Missing a once-daily dose would have a greater impact on anticoagulation. Some real world and retrospective studies found that a once-daily dosing regimen leads to better adherence and persistence to therapy, an important consideration for maintaining optimum anticoagulation. However, other studies have not found increased adherence among once daily regimens. Expert opinion: Prescription of DOACs should be tailored to the individual patient and dosing regimen is only one of the variables that should be taken into account.

Comparison of all-cause, stroke, and bleed-specific healthcare resource utilization among patients with non-valvular atrial fibrillation (NVAF) and newly treated with dabigatran or warfarin

BACKGROUND

We compared healthcare utilization outcomes and persistence among non-valvular atrial fibrillation (NVAF) patients newly treated with dabigatran or warfarin.

METHODS

Using a nationwide, US administrative claims database, a retrospective matched-cohort of newly diagnosed NVAF patients (age≥18 years) treated with dabigatran or warfarin (propensity score matched 1:1) in 01/01/2011-12/31/2013 was evaluated. All-cause, stroke-, and bleed-specific per patient per month (PPPM) healthcare resource utilization (HCRU), incidence rate of hospitalization for stroke or bleed, 30-day readmission, and persistence were reported.

RESULTS

In total, 18,890 dabigatran patients were matched to corresponding warfarin patients. Compared to warfarin users, dabigatran users PPPM had significantly fewer all-cause hospitalizations (0.04 vs 0.05), total outpatient visits (3.98 vs 5.87), and lower 30-day readmissions (14.5% vs 17.4%, all p < 0.001). Dabigatran users had lower incidence rate for stroke (0.65 vs 1.06) and bleed (1.69 vs 2.20), stroke (0.0006 vs 0.0011, p < 0.001) and bleed-specific hospitalizations (0.002 vs 0.003, p = 0.008), and stroke (0.03 vs 0.04, p < 0.001) and bleed-specific outpatient visits (0.07 vs 0.08, p = 0.018), and significantly lower non-persistence (62.1% vs 66.3%, p < 0.001).

CONCLUSION

Among newly diagnosed newly treated NVAF patients, dabigatran users had significantly lower all-cause, stroke- and bleed-specific HCRU, lower risk of hospitalization for stroke or bleed events, lower 30-day readmissions, and higher persistence than warfarin users.

Healthcare utilization and costs for patients initiating Dabigatran or Warfarin

Background

Novel oral anticoagulants (NOAC) such as dabigatran, when compared to warfarin, have been shown to potentially reduce the risk of stroke in patients with non-valvular atrial fibrillation (NVAF) together with lower healthcare resource utilization (HCRU) and similar total costs. This study expands on previous work by comparing HCRU and costs for patients newly diagnosed with NVAF and newly initiated on dabigatran or warfarin, and is the first study specifically in a Medicare population.

Methods

A retrospective matched-cohort study was conducted using data from administrative health care claims during the study period 01/01/2010–12/31/2012. Cox regression analyses were used to compare all-cause risk of first hospitalizations and emergency room (ER) visits. Medical, pharmacy, and total costs per-patient-per-month (PPPM) were compared between dabigatran and warfarin users.

Results

A total of 1110 patients initiated on dabigatran were propensity score-matched with corresponding patients initiated on warfarin. The mean number of hospitalizations (0.92 vs. 1.13, P = 0.012), ER visits (1.32 vs. 1.56, P < 0.01), office visits (21.43 vs. 29.41; P < 0.01), and outpatient visits (10.86 vs. 22.02; P < 0.01) were lower among dabigatran compared to warfarin users. Patients initiated on dabigatran had significantly lower risk of first all-cause ER visits [hazard ratio (HR): 0.84, 95% confidence interval (CI): 0.73–0.98] compared to those initiated on warfarin. Adjusted mean pharmacy costs PPPM were significantly greater for dabigatran users ($510 vs. $250, P < 0.001); however, mean medical costs PPPM ($1912 vs. $1956, P = 0.55) and mean total costs PPPM ($2381 vs. $2183, P = 0.10) were not significantly different compared to warfarin users.

Conclusions

Dabigatran users had significantly lower HCRU compared to warfarin users. In addition, dabigatran users had lower risk of all-cause ER visits. Despite higher pharmacy costs, the two cohorts did not differ significantly in medical or total all-cause costs.

Electronic supplementary material

The online version of this article (doi:10.1186/s12955-017-0705-x) contains supplementary material, which is available to authorized users.