Comparative Effectiveness and Safety Between Apixaban, Dabigatran, Edoxaban, and Rivaroxaban Among Patients With Atrial Fibrillation : A Multinational Population-Based Cohort Study

BACKGROUND

Current guidelines recommend using direct oral anticoagulants (DOACs) over warfarin in patients with atrial fibrillation (AF), but head-to-head trial data do not exist to guide the choice of DOAC.

OBJECTIVE

To do a large-scale comparison between all DOACs (apixaban, dabigatran, edoxaban, and rivaroxaban) in routine clinical practice.

DESIGN

Multinational population-based cohort study.

SETTING

Five standardized electronic health care databases, which covered 221 million people in France, Germany, the United Kingdom, and the United States.

PARTICIPANTS

Patients who were newly diagnosed with AF from 2010 through 2019 and received a new DOAC prescription.

MEASUREMENTS

Database-specific hazard ratios (HRs) of ischemic stroke or systemic embolism, intracranial hemorrhage (ICH), gastrointestinal bleeding (GIB), and all-cause mortality between DOACs were estimated using a Cox regression model stratified by propensity score and pooled using a random-effects model.

RESULTS

A total of 527 226 new DOAC users met the inclusion criteria (apixaban, n = 281 320; dabigatran, n = 61 008; edoxaban, n = 12 722; and rivaroxaban, n = 172 176). Apixaban use was associated with lower risk for GIB than use of dabigatran (HR, 0.81 [95% CI, 0.70 to 0.94]), edoxaban (HR, 0.77 [CI, 0.66 to 0.91]), or rivaroxaban (HR, 0.72 [CI, 0.66 to 0.79]). No substantial differences were observed for other outcomes or DOAC-DOAC comparisons. The results were consistent for patients aged 80 years or older. Consistent associations between lower GIB risk and apixaban versus rivaroxaban were observed among patients receiving the standard dose (HR, 0.72 [CI, 0.64 to 0.82]), those receiving a reduced dose (HR, 0.68 [CI, 0.61 to 0.77]), and those with chronic kidney disease (HR, 0.68 [CI, 0.59 to 0.77]).

LIMITATION

Residual confounding is possible.

CONCLUSION

Among patients with AF, apixaban use was associated with lower risk for GIB and similar rates of ischemic stroke or systemic embolism, ICH, and all-cause mortality compared with dabigatran, edoxaban, and rivaroxaban. This finding was consistent for patients aged 80 years or older and those with chronic kidney disease, who are often underrepresented in clinical trials.

PRIMARY FUNDING SOURCE

None.

Development and external validation of prediction models for adverse health outcomes in rheumatoid arthritis: A multinational real-world cohort analysis

BACKGROUND

Identification of rheumatoid arthritis (RA) patients at high risk of adverse health outcomes remains a major challenge. We aimed to develop and validate prediction models for a variety of adverse health outcomes in RA patients initiating first-line methotrexate (MTX) monotherapy.

METHODS

Data from 15 claims and electronic health record databases across 9 countries were used. Models were developed and internally validated on Optum® De-identified Clinformatics® Data Mart Database using L1-regularized logistic regression to estimate the risk of adverse health outcomes within 3 months (leukopenia, pancytopenia, infection), 2 years (myocardial infarction (MI) and stroke), and 5 years (cancers [colorectal, breast, uterine] after treatment initiation. Candidate predictors included demographic variables and past medical history. Models were externally validated on all other databases. Performance was assessed using the area under the receiver operator characteristic curve (AUC) and calibration plots.

FINDINGS

Models were developed and internally validated on 21,547 RA patients and externally validated on 131,928 RA patients. Models for serious infection (AUC: internal 0.74, external ranging from 0.62 to 0.83), MI (AUC: internal 0.76, external ranging from 0.56 to 0.82), and stroke (AUC: internal 0.77, external ranging from 0.63 to 0.95), showed good discrimination and adequate calibration. Models for the other outcomes showed modest internal discrimination (AUC < 0.65) and were not externally validated.

INTERPRETATION

We developed and validated prediction models for a variety of adverse health outcomes in RA patients initiating first-line MTX monotherapy. Final models for serious infection, MI, and stroke demonstrated good performance across multiple databases and can be studied for clinical use.

FUNDING

This activity under the European Health Data & Evidence Network (EHDEN) has received funding from the Innovative Medicines Initiative 2 Joint Undertaking under grant agreement No 806968. This Joint Undertaking receives support from the European Union's Horizon 2020 research and innovation programme and EFPIA.

Background rates of five thrombosis with thrombocytopenia syndromes of special interest for COVID-19 vaccine safety surveillance: Incidence between 2017 and 2019 and patient profiles from 38.6 million people in six European countries

Background

Thrombosis with thrombocytopenia syndrome (TTS) has been reported among individuals vaccinated with adenovirus‐vectored COVID‐19 vaccines. In this study, we describe the background incidence of non‐vaccine induced TTS in six European countries.

Methods

Electronic medical records from France, the Netherlands, Italy, Germany, Spain, and the United Kingdom informed the study. Incidence rates of cerebral venous sinus thrombosis (CVST), splanchnic vein thrombosis (SVT), deep vein thrombosis (DVT), pulmonary embolism (PE), and myocardial infarction or ischemic stroke, all with concurrent thrombocytopenia, were estimated among the general population of persons in a database between 2017 and 2019. A range of additional potential adverse events of special interest for COVID‐19 vaccinations were also studied in a similar manner.

Findings

A total of 38 611 617 individuals were included. Background rates ranged from 1.0 (95% CI: 0.7–1.4) to 8.5 (7.4–9.9) per 100 000 person‐years for DVT with thrombocytopenia, from 0.5 (0.3–0.6) to 20.8 (18.9–22.8) for PE with thrombocytopenia, from 0.1 (0.0–0.1) to 2.5 (2.2–2.7) for SVT with thrombocytopenia, and from 1.0 (0.8–1.2) to 43.4 (40.7–46.3) for myocardial infarction or ischemic stroke with thrombocytopenia. CVST with thrombocytopenia was only identified in one database, with incidence rate of 0.1 (0.1–0.2) per 100 000 person‐years. The incidence of non‐vaccine induced TTS increased with age, and was typically greater among those with more comorbidities and greater medication use than the general population. It was also more often seen in men than women. A large proportion of those affected were seen to have been taking antithrombotic and anticoagulant therapies prior to their event.

Interpretation

Although rates vary across databases, non‐vaccine induced TTS has consistently been seen to be a very rare event among the general population. While still remaining very rare, rates were typically higher among older individuals, and those affected were also seen to generally be male and have more comorbidities and greater medication use than the general population.

Long-Term Adherence and Persistence to Low-Dose Aspirin for the Prevention of Cardiovascular Disease: A Population-Based Cohort Study

METHODS

Using information from electronic health records in Germany and the United Kingdom (UK) in a common data model, we followed adults with ≥2 low-dose aspirin prescriptions (75-100 mg) during 2007-2018 for up to 10 years. Included individuals had no low-dose aspirin prescriptions in the year before the follow-up started (date of first low-dose aspirin prescription) and ≥12 months' observation. Adherence was determined using the medication possession ratio (MPR), and persistence was defined as continuous treatment disregarding gaps between prescriptions of <60 days; analyses were undertaken according to indication (primary/secondary CVD prevention).

RESULTS

We identified 144,717 low-dose aspirin users from Germany and 190,907 from the UK. Among patients with 5-10 years' follow-up, median adherence among secondary CVD prevention users was 60% in Germany and 75% in the UK. Among primary prevention users, median adherence was 50% for both countries. Persistence among secondary CVD prevention users was 58.3% at 2 years, 47.0% at 5 years, 35.2% at 10 years (Germany), and 67.5% at 2 years, 58.0% at 5 years, and 46.8% at 10 years (UK). Among primary CVD prevention users, persistence was 52.8% at 2 years, 41.6% at 5 years, 32.1% at 10 years (Germany), 56.3% at 2 years, 45.4% at 5 years, and 33.8% at 10 years (UK).

CONCLUSIONS

Long-term adherence and persistence to low-dose aspirin are suboptimal; efforts for improvement could translate into a lower CVD burden in the general population.

Time Trends and Treatment Pathways in Prescribing Individual Oral Anticoagulants in Patients with Nonvalvular Atrial Fibrillation: An Observational Study of More than Three Million Patients from Europe and the United States

BACKGROUND

Data directly comparing trends in the use of different oral anticoagulants (OACs) among patients with atrial fibrillation (AF) from different countries are limited. We addressed this using a large-scale network cohort study in the United States (US), Belgium, France, Germany, and the United Kingdom (UK).

METHODS

We used nine databases (claims or electronic health records) that had been converted into the Observational Medical Outcomes Partnership Common Data Model with analysis performed using open-source analytical tools. We identified adults with AF and a first OAC prescription, either vitamin K antagonist (VKA) or direct oral anticoagulant (DOAC), from 2010 to 2017. We described time trends in use, continuation, and switching.

RESULTS

In 2010, 87.5%-99.8% of patients started on a VKA. By 2017, the majority started on a DOAC: 87.0% (US), 88.3% (Belgium), 93.1% (France), 88.4% (Germany), and 86.1%-86.7% (UK). In the UK, DOACs became the most common starting OAC in 2015, 2-3 years later than elsewhere. Apixaban was the most common starting OAC by 2017, 50.2%-57.8% (US), 31.4% (Belgium), 45.9% (France), 39.5% (Germany), and 49.8%-50.5% (UK), followed by rivaroxaban, 24.8%-32.5% (US), 25.7% (Belgium), 38.4% (France), 24.9% (Germany), and 30.2%-31.2% (UK). Long-term treatment was less common in the US than in Europe, especially the UK. A minority of patients switched from their index OAC in the short and long term.

CONCLUSIONS

From 2010 to 2017, VKA use had significantly declined and DOAC use had significantly increased in the US and Europe. Apixaban was the most prescribed OAC in 2017, followed by rivaroxaban.

459. COVID-19 Hospitalization and 30-Day Readmission: A Cohort Study of U.S. Hospitals

Background

Evidence on outcomes after COVID-19 hospitalization is limited. This study aimed to characterize 30-day readmission beyond the initial COVID-19 hospitalization.

Methods

This descriptive retrospective cohort study included adult patients admitted between 07/01/2020 and 01/31/2021 with a discharge diagnosis of COVID-19 (ICD-10-CM: U07.1), using a large hospital inpatient chargemaster with a linked open claims dataset. The first COVID-19 hospitalization was considered index hospitalization; baseline was defined as first 2 days of index hospitalization; readmission was assessed within 30 days of discharge from index hospitalization. We describe the demographics, treatments and outcomes of the index hospitalization and readmission.

Results

For index hospitalization, we identified 111,624 COVID-19 patients from 327 hospitals across US. Mean age was 63 and 54% were male. Over the study period, use of remdesivir (RDV) increased from 11% to 50% while use of steroids (66% -73%) and anticoagulants (32% - 35%) remained relatively stable (Figure 1). Overall, 21% required ICU or CCU admission, 13% died, and median length of stay (LOS) was 7 days (range 4 -11 days). Among 61,182 (55%) with ≥ 30-day follow-up post discharge, all-cause 30-day readmission was 16% and remained stable (15% - 17%) over the study period; median days to readmission was 6 days (range 1-30). All-cause readmission (13 % vs 17%) was lower in patients treated with RDV during index hospitalization over time (Figure 2), particularly in those requiring high flow oxygen (17% vs 18%), low flow oxygen (13% vs 16%) or no oxygen (12% vs 17%), but not in ECMO or invasive ventilation (33% vs 29%). Compared to non-readmitted, readmitted patients were older (60 vs 65), had more comorbidities such as COPD (24% vs 37%) (see Table 1) and LOS (6 vs 7 days) in index hospitalization. Overall, the most frequent diagnoses of readmission were COVID-19 (63%), other viral pneumonia (36%), and acute respiratory failure with hypoxia (34%).

Conclusion

In a large, geographically diverse cohort of hospitalized COVID-19 patients, 16% required readmission, especially in those with greater age and comorbidities. Over the study period, all-cause readmission remained stable and was lower in RDV treated patients.

Disclosures

Essy Mozaffari, PharmD, MPH, MBA, Gilead Sciences (Employee, Shareholder) Shuting Liang, MPH, Gilead Sciences (Employee) Henry Morgan Stewart, PhD, IQVIA (Employee) Mark Thrun, MD, Gilead Sciences (Employee, Shareholder) Paul Hodgkins, PhD, MSc, Gilead Sciences (Employee, Shareholder) Richard Haubrich, MD, Gilead Sciences (Employee, Shareholder)

Development and validation of a prognostic model predicting symptomatic hemorrhagic transformation in acute ischemic stroke at scale in the OHDSI network

BACKGROUND AND PURPOSE

Hemorrhagic transformation (HT) after cerebral infarction is a complex and multifactorial phenomenon in the acute stage of ischemic stroke, and often results in a poor prognosis. Thus, identifying risk factors and making an early prediction of HT in acute cerebral infarction contributes not only to the selections of therapeutic regimen but also, more importantly, to the improvement of prognosis of acute cerebral infarction. The purpose of this study was to develop and validate a model to predict a patient's risk of HT within 30 days of initial ischemic stroke.

METHODS

We utilized a retrospective multicenter observational cohort study design to develop a Lasso Logistic Regression prediction model with a large, US Electronic Health Record dataset which structured to the Observational Medical Outcomes Partnership (OMOP) Common Data Model (CDM). To examine clinical transportability, the model was externally validated across 10 additional real-world healthcare datasets include EHR records for patients from America, Europe and Asia.

RESULTS

In the database the model was developed, the target population cohort contained 621,178 patients with ischemic stroke, of which 5,624 patients had HT within 30 days following initial ischemic stroke. 612 risk predictors, including the distance a patient travels in an ambulance to get to care for a HT, were identified. An area under the receiver operating characteristic curve (AUC) of 0.75 was achieved in the internal validation of the risk model. External validation was performed across 10 databases totaling 5,515,508 patients with ischemic stroke, of which 86,401 patients had HT within 30 days following initial ischemic stroke. The mean external AUC was 0.71 and ranged between 0.60-0.78.

CONCLUSIONS

A HT prognostic predict model was developed with Lasso Logistic Regression based on routinely collected EMR data. This model can identify patients who have a higher risk of HT than the population average with an AUC of 0.78. It shows the OMOP CDM is an appropriate data standard for EMR secondary use in clinical multicenter research for prognostic prediction model development and validation. In the future, combining this model with clinical information systems will assist clinicians to make the right therapy decision for patients with acute ischemic stroke.

Compressive straining of bilayer phosphorene leads to extraordinary electron mobility at a new conduction band edge

By means of hybrid DFT calculations and the deformation potential approximation, we show that bilayer phosphorene under slight compression perpendicular to its surface exhibits extraordinary room temperature electron mobility of order 7 × 10(4) cm(2) V(-1) s(-1). This is approximately 2 orders of magnitude higher than is widely reported for ground state phosphorenes and is the result of the emergence of a new conduction band minimum that is decoupled from the in-plane acoustic phonons that dominate carrier scattering.

Strain and orientation modulated bandgaps and effective masses of phosphorene nanoribbons

Passivated phosphorene nanoribbons, armchair (a-PNR), diagonal (d-PNR), and zigzag (z-PNR), were investigated using density functional theory. Z-PNRs demonstrate the greatest quantum size effect, tuning the bandgap from 1.4 to 2.6 eV when the width is reduced from 26 to 6 Å. Strain effectively tunes charge carrier transport, leading to a sudden increase in electron effective mass at +8% strain for a-PNRs or hole effective mass at +3% strain for z-PNRs, differentiating the (mh*/me*) ratio by an order of magnitude in each case. Straining of d-PNRs results in a direct to indirect band gap transition at either -7% or +5% strain and therein creates degenerate energy valleys with potential applications for valleytronics and/or photocatalysis.

Histologic fate of dermal grafts following implantation for temporomandibular joint meniscal perforation: a preliminary study

A study was carried out to evaluate the histologic changes of meniscus perforation repair associated with dermal grafts to the temporomandibular joint of cynomolgus monkeys (Macaca fascicularis) following surgical perforation of the meniscus. Dermal grafts were studied histologically at 3-week, 6-week, 3-month, and 6-month intervals. Results showed early attachment of the dermal graft to the meniscus, followed by gradual incorporation of the graft into the meniscus and subsequent return of the meniscal-graft complex to a normal meniscal architecture.

Cherubism: report of a nonfamilial case

A case of nonfamilial cherubism and a review of literature have been reported. A diagnosis of cherubism was based on clinical and histopathologic examinations.