Initiation Of Oral Anticoagulation Research Articles

Racial and Ethnic Disparities in Initiation of Direct Oral Anticoagulants Among Medicare Beneficiaries

The influence of race and ethnicity on initiation of direct oral anticoagulants (DOACs) is relatively understudied in Medicare data. To investigate disparities in the initiation of DOACs compared with warfarin by race, ethnicity, and social vulnerability. This retrospective cohort study used a 50% sample of Medicare fee-for-service data from January 1, 2010, to December 31, 2019 (mean patient enrollment duration, 7.7 years). Analysis took place between January 2023 and February 2024. A cohort of older adults (aged ≥65 years) with atrial fibrillation who newly initiated warfarin or DOACs (dabigatran, rivaroxaban, apixaban, and edoxaban) was identified. Patients were classified as non-Hispanic White, non-Hispanic Black, and Hispanic. The likelihood of starting use of DOACs compared with warfarin was modeled, adjusting for race, ethnicity, age, sex, county-level social vulnerability, and other clinical factors. Among 950 698 anticoagulation initiations, consisting of 680 974 DOAC users and 269 724 warfarin users (mean [SD] age, 78.5 [7.6] years; 52.6% female), 5.2% were Black, 4.3% were Hispanic, and 86.7% were White. During the 10-year study period, DOAC use increased for all demographic groups. After adjustment, compared with White patients, Black patients were 23% less likely (adjusted odds ratio [AOR, 0.77; 95% CI, 0.75-0.79) and Hispanic patients were 13% less likely (AOR, 0.87; 95% CI, 0.85-0.89) to initiate DOAC use. Disparities in DOAC initiation were greatest among Black patients in the earlier years but attenuated during the study period. For instance, in 2010, the OR of Black patients initiating DOACs was 0.54 (95% CI, 0.50-0.57), attenuating linearly over time to 0.69 by 2013 (95% CI, 0.65-0.74) and 0.83 (95% CI, 0.78-0.89) by 2017. By 2019, these differences became nonsignificant (OR, 1.08; 95% CI, 0.99-1.18). In this cohort study of Medicare patients with atrial fibrillation, Black and Hispanic patients were less likely to initiate DOACs for atrial fibrillation, although these differences diminished over time. Identifying the factors behind these early disparities is crucial for ensuring equitable access to novel therapies as they emerge for Black and Hispanic populations.

Effectiveness, utilisation and cost associated with implantable loop recorders versus external monitors after ischaemic or cryptogenic stroke

ObjectiveImplantable loop recorders (ILRs) are increasingly used for long-term rhythm monitoring after ischaemic and cryptogenic stroke, with the goal of detecting atrial fibrillation (AF) and subsequent initiation of oral anticoagulation...

Diagnostic yield of implantable loop recorders: results from the hellenic registry

ObjectiveImplantable loop recorders (ILRs) are increasingly being used for long-term cardiac monitoring in different clinical settings. The aim of this study was to investigate the real-world performance of ILRs—including the time to diagnosis—in unselected patients with different ILR indications. Methods and ResultsIn this multicenter, observational study, 871 patients with an indication of pre-syncope/syncope (61.9%), unexplained palpitations (10.4%), and atrial fibrillation (AF) detection with a history of cryptogenic stroke (CS) (27.7%) underwent ILR implantation. The median follow-up was 28.8 ± 12.9 months. In the presyncope/syncope group, 167 (31%) received a diagnosis established by the device. Kaplan-Meier estimates indicated that 16.9% of patients had a diagnosis at 6 months, and the proportion increased to 22.5% at 1 year. Of 91 patients with palpitations, 20 (22%) received a diagnosis based on the device. The diagnosis was established in 12.2% of patients at 6 months, and the proportion increased to 13.3% at 1 year. Among 241 patients with CS, 47 (19.5%) were diagnosed with AF. The diagnostic yield of the device was 10.4% at 6 months and 12.4% at 1 year. In all cases, oral anticoagulation was initiated. Overall, ILR diagnosis altered the therapeutic strategy in 26.1% of the presyncope/syncope group, 2.2% of the palpitations group, and 3.7% of the CS group in addition to oral anticoagulation initiation. ConclusionIn this real-world patient population, ILR determines diagnosis and initiates new therapeutic management for nearly one-fourth of patients. ILR implantation is valuable in the evaluation of patients with unexplained presyncope/syncope, CS, and palpitations.

Direct Oral Anticoagulation in Lung Transplant Recipients.

Presently, the management of direct oral anticoagulants lacks specific guidelines for patients before and after transplant, particularly for lung transplant recipients. We aimed to consolidate the existing literature on direct oral anticoagulants and explore their implications in lung transplant recipients. We conducted a comprehensive search in PubMed and Google Scholar databases for studies published between January 2000 and December 2022, using specific search terms. We only included studies involving lung transplant recipients and focusing on direct oral anticoagulants. Five relevant publications were identified, providing varied insights. None of the studies specifically addressed bleeding complications associated with direct oral anticoagulants in lung transplant recipients. Limited details were available on the type of solid-organ transplant or the specific direct oral anticoagulant used in these studies. Varied bleeding complications associated with direct oral anticoagulants in lung transplant recipients were reported, but studies lacked specificity on transplant type and direct oral anticoagulant variations. Notably, the incidence of venous thrombotic embolism in lung transplant recipients was comparatively higher than in other solid-organ transplant recipients, potentially linked to factors such as corticosteroid therapy, calcineurin inhibitors, and cytomegalovirus infections. Our synthesis on findings of use of direct oral anticoagulant in lung transplant recipients emphasized challenges of managing these medications in urgent transplant situations. Recommendations from experts suggested caution in initiation of direct oral anticoagulants posttransplant until stability in renal and hepatic function is achieved. The limited evidence on safety of direct oral anticoagulants in lung transplant recipients underscores the need for further research and guidance in this specific patient population.

Benefit and risk of oral anticoagulant initiation strategies in patients with atrial fibrillation and cancer: a target trial emulation using the SEER-Medicare database.

Oral anticoagulants (OACs) are recommended for patients with atrial fibrillation (AFib) having CHA2DS2-VASc score ≥ 2. However, the benefits of OAC initiation in patients with AFib and cancer at different levels of CHA2DS2-VASc is unknown. We included patients with new AFib diagnosis and a record of cancer (breast, prostate, or lung) from the 2012-2019 Surveillance, Epidemiology, and End Results (SEER)-Medicare database (n = 39,915). Risks of stroke and bleeding were compared between 5 treatment strategies: (1) initiated OAC when CHA2DS2-VASc ≥ 1 (n = 6008), (2) CHA2DS2-VASc ≥ 2 (n = 8694), (3) CHA2DS2-VASc ≥ 4 (n = 20,286), (4) CHA2DS2-VASc ≥ 6 (n = 30,944), and (5) never initiated OAC (reference group, n = 33,907). Confounders were adjusted using inverse probability weighting through cloning-censoring-weighting approach. Weighted pooled logistic regressions were used to estimate treatment effect [hazard ratios (HRs) and 95% confidence interval (95% CIs)]. We found thatonly patients who initiated OACs at CHA2DS2-VASc ≥ 6 had lower risk of stroke compared without OAC initiation (HR 0.64, 95% CI 0.54-0.75). All 4 active treatment strategies had reduced risk of bleeding compared to non-initiators, with OAC initiation at CHA2DS2-VASc ≥ 6 being the most beneficial strategy (HR = 0.49, 95% CI 0.44-0.55). In patients with lung cancer or regional/metastatic cancer, OAC initiation at any CHA2DS2-VASc level increased risk of stroke and did not reduce risk of bleeding (except for Regimen 4). In conclusion,among cancer patients with new AFib diagnosis, OAC initiation at higher risk of stroke (CHA2DS2-VASc score ≥ 6) is more beneficial in preventing ischemic stroke and bleeding. Patients with advanced cancer or low life-expectancy may initiate OACs when CHA2DS2-VASc score ≥ 6.

Patient Characteristics Associated With Using Transcatheter Left Atrial Appendage Occlusion Versus Oral Anticoagulants for Atrial Fibrillation.

Transcatheter left atrial appendage occlusion (LAAO) is an alternative to oral anticoagulants (OACs) for stroke prevention in patients with atrial fibrillation, but the predictors of LAAO use in routine care are unclear. We aimed to assess the utilization trends of LAAO and compare the change in characteristics of LAAO users versus OACs since its marketing. Using the US Medicare claims database (March 15, 2015, to December 31, 2020), we identified patients with atrial fibrillation, ≥65 years, and CHA2DS2-VASc score ≥2 (men) or ≥3 (women), with either first implantation of an LAAO device or initiation of OACs, including apixaban, dabigatran, rivaroxaban, edoxaban, or warfarin. Patient characteristics, measured 365 days before the first LAAO or OAC use date, were compared using logistic regression. There were 30 058 LAAO recipients (mean age, 77.74 years; female, 42.1%) and 792 600 OAC initiators (mean age, 78.48; female, 53.3%). In 2020, patients had higher odds of initiating LAAO use than in 2015 (0.52 versus 9.32%; adjusted odds ratio [aOR], 13.64 [95% CI, 12.56-14.81]). Old age (ie, >85 versus 65-75 years; aOR, 0.84 [95% CI, 0.80-0.88]), female sex (aOR, 0.74 [95% CI, 0.71-0.76]), Black race (aOR, 0.63 [95% CI, 0.58-0.68]) versus White race, and Medicaid eligibility (aOR, 0.61 [95% CI, 0.58-0.64]) were associated with lower odds of receiving LAAO. Among clinical characteristics, frailty, cancer, fractures, and venous thromboembolism were associated with lower odds of LAAO use, while history of intracranial and extracranial bleeding, coagulopathy, and falls were associated with higher odds of receiving LAAO. Among patients with atrial fibrillation receiving stroke-preventive therapy, LAAO use increased rapidly from 2015 to 2020 and was positively associated with the risk factors for OAC complications but negatively associated with old age, advanced frailty, and cancer. Black race and female sex were associated with a lower likelihood of receiving LAAO.

Delayed treatment initiation of oral anticoagulants among Medicare patients with atrial fibrillation

Study objectiveThis study aimed to identify factors associated with delayed oral anticoagulant (OAC) treatment initiation among atrial fibrillation (AF) patients in United States (US) clinical practice. ParticipantsMedicare beneficiaries newly diagnosed with AF without moderate-to-severe mitral stenosis or a mechanical heart valve, were aged ≥65 years and prescribed OAC on or after 10/1/2015 through 2019 were included. Delayed and early OAC initiation were defined as >3 months and 0–3 months initiation from first AF diagnosis, respectively. Main outcome measuresAssociation between delayed OAC initiation and patient demographics, clinical and index OAC coverage and formulary characteristics was examined using multivariable logistic regression. ResultsA total of 446,441 patients met the inclusion criteria; 30.0 % (N = 131,969) were identified as delayed and 70.0 % (N = 314,472) as early OAC initiation. Median age for both cohorts was 78 years. In the early and delayed OAC cohorts, 47.1 % and 47.6 % were male and 88.8 % and 86.6 %, were White, respectively. Factors associated with delayed OAC initiation (odds ratio; 95 % confidence interval) included Black race (1.29; 1.25 to 1.33), west region (1.29; 1.26 to 1.32), comorbidities such as dementia (1.27; 1.23 to 1.30), recent bleeding hospitalization (1.22; 1.18 to 1.27), prior authorization (1.69; 1.66 to 1.71), tier 4 formulary for index OAC at AF diagnosis (1.26; 1.22 to 1.30). ConclusionOur study revealed that nearly one-third of Medicare patients with AF experienced delayed OAC initiation. Key patient characteristics found to be associated with delayed OAC initiation included race and ethnicity, comorbidities, and formulary restrictions.

Incidence and patterns of atrial fibrillation after catheter ablation of typical atrial flutter-the FLUTFIB study.

In patients with atrial flutter (AFL), ablation of the cavotricuspid isthmus (CTI) is a highly effective procedure to prevent AFL recurrence, but atrial fibrillation (AF) may occur during follow-up. The presented FLUTFIB study was designed to identify the exact incidence, duration, timely occurrence, and associated symptoms of AF after CTI ablation using continuous cardiac monitoring via implantable loop recorders. One hundred patients with AFL without prior AF diagnosis were included after CTI ablation (mean age 69.7 ± 9.7 years, 18% female) and received an implantable loop recorder for AF detection. After a median follow-up of 24 months 77 patients (77%) were diagnosed with AF episodes. Median time to first AF occurrence was 180 (43-298) days. Episodes lasted longer than 1 h in most patients (45/77, 58%). Forty patients (52%) had AF-associated symptoms.Patients with and without AF development showed similar baseline characteristics and neither HATCH- nor CHA2DS2-VASc scores were predictive of future AF episodes. Oral anticoagulation (OAC) was stopped during FU in 32 patients (32%) and was re-initiated after AF detection in 15 patients (15%). No strokes or transient ischaemic attack episodes were observed during follow-up. This study represents the largest investigation using implantable loop recorders (ILRs) to detect AF after AFL ablation and shows a high incidence of AF episodes, most of them being asymptomatic and lasting longer than 1 h. In anticipation of trials determining the duration of AF episodes that should trigger OAC initiation, these results will help to guide anticoagulation management after CTI ablation.

Update of Anticoagulation Use in Cardioembolic Stroke With a Special Reference to Endovascular Treatment.

Cardioembolic stroke is a major cause of morbidity, with a high risk of recurrence, and anticoagulation represents the mainstay of secondary stroke prevention in most patients. The implementation of endovascular treatment in routine clinical practice complicates the decision to initiate anticoagulation, especially in patients with early hemorrhagic transformation who are considered at higher risk of hematoma expansion. Late hemorrhagic transformation in the days and weeks following stroke remains a potentially serious complication for which we still do not have any established clinical or radiological prediction tools. The optimal time to initiate therapy is challenging to define since delaying effective secondary prevention treatment exposes patients to the risk of recurrent embolism. Consequently, there is clinical equipoise to define and individualize the optimal timepoint to initiate anticoagulation combining the lowest risk of hemorrhagic transformation and ischemic recurrence in cardioembolic stroke patients. In this narrative review, we will highlight and critically outline recent observational and randomized relevant evidence in different subtypes of cardioembolic stroke with a special focus on anticoagulation initiation following endovascular treatment. We will refer mainly to the commonest cause of cardioembolism, non-valvular atrial fibrillation, and examine the possible risk and benefit of anticoagulation before, during, and shortly after the acute phase of stroke. Other indications of anticoagulation after ischemic stroke will be briefly discussed. We provide a synthesis of available data to help clinicians individualize the timing of initiation of oral anticoagulation based on the presence and extent of hemorrhagic transformation as well as stroke severity.

Anticoagulation-Associated Bleeding in Patients Screened for Atrial Fibrillation versus Usual Care-A Post Hoc Analysis from the LOOP Study.

Background Atrial fibrillation (AF) prevalence is rising; however, data on the bleeding risks associated with the detection of subclinical AF are needed. Objective Our objective was to determine the bleeding increment associated with implantable loop recorder (ILR) screening for subclinical AF and subsequent anticoagulation initiation compared with usual care. Methods This post hoc study utilized LOOP trial data from 6,004 elderly patients with stroke risks randomized to either ILR ( n = 1,503) or usual care ( n = 4,503). The mean follow-up time was 64.5 months, and none were lost to follow-up. The primary exposure was the initiation of oral anticoagulation, and the main outcome was the risk of major bleeding events following initiation of oral anticoagulants (OACs), determined by time-dependent cox regression. Second, we investigated antithrombotic prescription patterns and major bleeding events after antiplatelet treatment and in subgroups. Results OAC was initiated in 1,019 participants with a mean age (years) of 78.8 (± 4.67) in control versus 77.0 (± 4.84) in ILR, p < 0.0001. Altogether did 202 participants end or pause OAC treatment. Among AF patients (n = 910) had 40 (28%) completely ended OAC and 105 (72%) temporarily paused OAC during follow-up. Major bleeding events totaled 221 (3.7%). Forty-seven major bleeding events followed an OAC initiation in 1,019 participants (4.6%); 26 versus 21 events in the control and ILR groups, respectively. The hazard ratio (HR) for major bleeding after OAC initiation compared with before initiation was 2.08 (1.50-2.90) p < 0.0001 overall, 2.81 (1.82-4.34) p < 0.0001 for control and 1.32 (0.78-2.23) p = 0.31 for the ILR group ( p = 0.07 for interaction). Antiplatelet treatment resulted in an overall adjusted HR of 1.3 (0.96-1.75) p = 0.09. For OAC users aged ≥75 years in the ILR group, the rate of major bleeding was 1.73 (0.92-2.96) compared with 0.84 (0.36-1.66) for an age <75 years, and the rate of the corresponding control subgroup aged ≥75 years was 2.20 (1.23-3.63) compared with 1.64 (0.82-2.93) for an age <75 years. Conclusion The individual risk of major bleeding increased twofold after initiation of oral anticoagulation for all patients in this study. However, the patients screened for subclinical AF did not have a higher bleeding risk after initiation of anticoagulation compared with those in usual care. Trial Registration: The LOOP study is registered at ClinicalTrials.gov, identifier: NCT020364 50.

Challenging anticoagulation decisions in atrial fibrillation: a narrative review.

Atrial fibrillation (AF) is common and warrants consideration of oral anticoagulant (OAC) medication. Usually, the decision is straightforward, following the pathway outlined in the European Society of Cardiology's guideline; however, certain situations fall outside of this evidence base - such as a diagnosis of subclinical AF made via implanted devices or wearable electrocardiogram monitors, or alternatively diagnosis of 'secondary AF' following a major stressor. Subclinical AF is associated with stroke, though not to the extent of clinical AF, and the benefits of anticoagulation appear to be lower. Longer episodes are more clinically meaningful, and recent randomised controlled trials have demonstrated that some patients derive benefit from OAC. Similarly, when AF is triggered by sepsis or non-cardiac surgery, specific evidence supporting OAC initiation is lacking and clinician behaviour is variable. Observational data demonstrate poorer outcomes in these patients, implying that the perception of a transient, reversible phenomenon may not be correct. Contrastingly, cardiac surgery very frequently induces AF, and the benefits of anticoagulation rarely outweigh the risks of bleeding. Following ischaemic stroke, recent evidence suggests that early (re-)initiation of OAC should be considered as this does not increase the risk of haemorrhagic transformation as previously hypothesised. This narrative review summarises the available literature and outlines, where possible, practical advice for clinicians facing these common clinical dilemmas.

Do Proton Pump Inhibitors Reduce Upper Gastrointestinal Bleeding in Older Patients with Atrial Fibrillation Treated with Oral Anticoagulants? A Nationwide Cohort Study in France.

Proton pump inhibitors (PPIs) are largely used in older adults and data are needed in off-label indications, such as the prevention of upper gastrointestinal bleeding (UGIB) in patients receiving oral anticoagulants (OACs). This study aimed to assess whether PPIs reduce the risk of UGIB in patients initiating oral anticoagulation. We conducted a longitudinal study based on the French national health database. The study population included 109,693 patients aged 75-110 years with a diagnosis of atrial fibrillation who initiated OACs [vitamin K antagonist (VKA) or direct OAC(DOAC)] between 2012 and 2016. We used multivariable Cox models weighted by inverse of probability of treatment to estimate the adjusted hazard ratio (aHR) of UGIB between PPI users and nonusers over a 6- and 12-month follow-up. PPI users represented 23% of the study population (28% among VKA initiators and 17% among DOAC initiators). The mean age (83 ± 5.3 years) and proportion of women (near 60%) were similar between groups. The risk of UGIB in the first 6 months after initiation of OAC decreased by 20% in PPI users compared with PPI nonusers [aHR6 months = 0.80, 95% confidence interval (CI) 0.65-0.98], but was not significantly modified when the follow-up was extended to 12 months (aHR12 months = 0.90, 95% CI 0.76-1.07), with a stronger effect among patients treated with vitamin K antagonists (aHR6 months = 0.73, 95% CI 0.58-0.93; aHR12 months = 0.81, 95% CI 0.67-0.99). This study suggests that PPIs were associated with reduced risk of gastrointestinal bleeding after initiation of oral anticoagulation in older patients with atrial fibrillation, particularly within 6 months after initiation of an antivitamin K antagonist.

Adherence to direct or vitamin K antagonist oral anticoagulants in patients with atrial fibrillation: a long-term observational study

Our objectives were to measure long-term adherence to oral anticoagulants (OACs) in patients with atrial fibrillation (AF) and to identify patient factors associated with adherence. Using linked, population-based administrative data from British Columbia, Canada, an incident cohort of adults prescribed OACs for AF was identified. We calculated the proportion of days covered (PDC) as a time-dependent covariate for each 90-day window from OAC initiation until the end of follow-up. Associations between patient attributes and adherence were assessed using generalized mixed effect linear regression models. 30,264 patients were included. Mean PDC was 0.69 (SD 0.28) over a median follow-up of 6.7 years. 54% of patients were non-adherent (PDC < 0.8). After controlling for confounders, factors positively associated with adherence were number of drug class switches, history of stroke or transient ischemic attack, history of vascular disease, time since initiation, and age. Age > 75 years at initiation, polypharmacy (among VKA users only), and receiving DOAC (vs. VKA) were negatively associated with adherence. PDC decreased over time for VKA users and increased for DOAC users. Over half of AF patients studied were, on average, nonadherent to OAC therapy and missed 32% of their doses. Several patient factors were associated with higher or lower adherence, and adherence to VKA declined during therapy while DOAC adherence increased slightly over time. To min im ize the risk stroke, adherence-supporting interventions are needed for all patients with AF, particularly those aged > 75 years, those with prior stroke or vascular disease, VKA users with polypharmacy, and DOAC recipients.

Anticoagulant Prescribing Patterns in New-Onset Atrial Fibrillation After Cardiac Surgery

BackgroundPostoperative atrial fibrillation (POAF) is a common complication after cardiac surgery and is associated with an increased risk of thromboembolic stroke. Recommendations regarding the optimal anticoagulant, timing of initiation, and duration of therapy remain uncertain. MethodsAdministrative databases were used to include adult patients who presented with POAF after cardiac surgery between January 1, 2015, and December 31, 2020. Key exclusion criteria included preexisting atrial fibrillation, mechanical valve replacement, or anticoagulant prescription fill within 6 months before the index admission. ResultsA total of 3214 of patients were included, and 878 (27.3%) were prescribed an oral anticoagulant (OAC) on discharge, with 536 (61%) prescribed warfarin and 342 (39%) prescribed a direct OAC. More than half of the patients (56.1%) stopped their OAC by 6 months. There was no difference in stroke or systemic embolism at 30 days, 3 months, or 6 months between those with and without anticoagulation prescribed. However, those on any OAC had higher rates of any bleeding at all time points. ConclusionsA minority of patients who presented with POAF after cardiac surgery were prescribed OAC, with warfarin being the most common agent. OAC initiation was associated with increased bleeding risk, warranting special consideration when assessing a patient’s risk of stroke with the increased risk of bleeding, particularly in the postoperative period.

COVID-19 pandemic and initiation of treatment for atrial fibrillation: a nationwide analysis of claims data

BackgroundThe COVID-19 pandemic profoundly disrupted the delivery of medical care. It remains unclear whether individuals diagnosed with new onset disease during the pandemic were less likely to initiate treatments after diagnosis. We sought to evaluate changes in the treatment initiation of patients newly diagnosed with atrial fibrillation (AF) after the onset of the COVID-19 pandemic.MethodsIn this retrospective cohort study, we identified individuals with incident AF from 01/01/2016–09/30/2021 using Optum’s de-identified Clinformatics® Data Mart Database. The primary outcome was initiation of oral anticoagulation (OAC) within 30 days of AF diagnosis. Secondary outcomes included initiation of OAC within 180 days of diagnosis, initiation of warfarin, direct oral anticoagulants (DOACs), rhythm control medications and electrical cardioversion within 30 days of diagnosis. We constructed interrupted time series analyses to examine changes in the outcomes following the onset of the pandemic.ResultsA total of 573,524 patients (age 73.0 ± 10.9 years) were included in the study. There were no significant changes in the initiation of OAC, DOAC, and rhythm control medications associated with the onset of the pandemic. There was a significant decrease in initiation of electrical cardioversion associated with the onset of the pandemic. The rate of electronic cardioversion within 30 days of diagnosis decreased by 4.9% per 1,000 patients after the onset of the pandemic and decreased by about 35% in April 2020, compared to April 2019, from 5.53% to 3.58%.ConclusionThe COVID-19 pandemic did not affect the OAC initiation within 30 days of AF diagnosis but was associated with a decline in the provision of procedures for patients newly diagnosed with AF.

The incidence of atrial fibrillation, new oral anticoagulation, stroke, and significant bleeds in patients receiving a new dual-chamber pacemaker

Background and objectivesAtrial fibrillation and flutter (AF/AFL) can be easily detected in patients who have a dual-chamber pacemaker (PM). This can result in a high detection rate of these arrhythmias especially if patients are monitored remotely and detection limits are sensitive. Materials and methodsA single-center retrospective registry analysis of 1,285 consecutive AF/AFL and anticoagulation naïve patients from a limited geographical area undergoing implantation of a new dual-chamber PM (between 2013 and 2019). Seven-year follow-up data for incident AF/AFL, initiation of new oral anticoagulation and for incident strokes and bleeds was obtained from an in-depth review of all relevant patient records including written medical records and death certificates detailing causes of death. ResultsDuring the follow-up, mortality reached 22.2 % and cumulative incidence of AF/AFL, new anticoagulation, strokes, and bleeds were 52.6 %, 40.4 %, 4.7 % and 10.4 %. In 92.6 % of the cases, AF/AFL was discovered by PM. Remote monitoring was initiated in 67 % (n = 856). Risk factor adjusted mortality in this group was significantly lower when compared to patients in regular out-patient clinic controls (HR 0.45, 95 % CI 0.35–0.57). Despite of their better overall prognosis, the AF/AFL was discovered, and oral anticoagulation was initiated more often in remote monitoring group (HR 1.58, 95 % CI 1.23–1.79 for AF/AFL and HR 1.67, 95 % CI 1.33–2.09 for anticoagulation). There was no significant difference in the incidence of strokes or bleeds. ConclusionsThe incidence of new AF/AFL is high in this population. Remote monitoring is associated with higher diagnostic yields of AF/AFL and initiated anticoagulation, but not with stroke and significant bleeds.

Anticoagulation-associated bleeding in patients randomised to screening for atrial fibrillation or usual care

Abstract Background Atrial fibrillation (AF) prevalence is rising, strongly aided by population ageing and increased awareness. Detection and treatment of subclinical AF may help mitigate stroke risk, but could increase iatrogenic complications. Purpose To evaluate whether detection of subclinical AF using implantable loop recorder (ILR) and subsequent initiation of oral anticoagulant (OAC) enhances the risk of major bleeding in elderly individuals with stroke risk factors. Methods This was a post-hoc analysis of a trial which randomised 6004 participants without known AF but with stroke risk factors in a 1:3 ratio to either ILR-screening for AF and OAC initiation upon AF episodes lasting ≥6 minutes or usual care (Control group). We examined the risk of major bleeding using OAC initiation as a time-varying exposure (figure 1) in Cox regression models, and similarly for the use of antiplatelets. Further, we estimated the incidence rates of OAC/antiplatelet initiation and discontinuation along with the distribution of major bleeding events according to drug exposure and subgroups. Results A total of 1019 participants (17%) initiated OAC; 578 (12.8%) in Control group vs. 441 (29.4%) in ILR group, with a mean age of 78.8 (±4.7) years in Control vs. 77.0 (±4.8) in ILR group, p&amp;lt;0.0001. Major bleeding events totalled 221 (3.7%) with 47 of these occurring after OAC initiation (4.6% of all OAC-users); 26 (4.5%) vs. 21 (4.8%) in Control and ILR group, respectively. Without the use of OAC or antiplatelets the overall rate of major bleeding was 0.44 (0.33-0.57) per 100-perosn years compared to 1.54 (1.13-2.05) after OAC initiation. For the individual person, the hazard ratio for major bleeding after OAC initiation was 2.08 (1.50-2.90) p&amp;lt;0.0001 compared to before initiation (Control: 2.81 (1.82-4.34) p&amp;lt;0.0001, ILR: 1.32 (0.78-2.23) p=0.31, p=0.07 for interaction)(table 1), similarly was usage of antiplatelet associated with a hazard ratio of 1.3 (0.96-1.75) p=0.09. For OAC users ≥75 years, the rate of major bleeding was 1.96 (1.30-2.83)(Control: 2.20 (1.23-3.63), ILR: 1.73 (0.92-2.96)), compared to 1.17 (0.70-1.83) among users &amp;lt;75 years (Control: 1.64 (0.82-2.93), ILR: 0.84 (0.36-1.66)). After OAC initiation, the discontinuation rate in the Control and ILR group was 9.60 (7.9-11.6) and 6.15 (4.95-7.55), respectively, while the rate of antiplatelet discontinuation was 7.44 (6.92-7.99) and 12.24 (10.9-13.4) in the Control and ILR group. Conclusion This post-hoc study of a randomised study found a two-fold risk increase of major bleeding after OAC initiation on individual basis compared with before, but this increase did not seem augmented by AF screening and treatment. A weaker signal was seen for antiplatelets. The OAC-associated bleeding risk was markedly higher in the elderly population. Finally, discontinuations of OAC and antiplatelets were common throughout follow-up.

Factors associated with delayed treatment initiation of oral anticoagulants among Medicare patients with atrial fibrillation

Abstract Background Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia in the United States (US) and is associated with increased risk of stroke.1 Oral anticoagulants (OACs) are the primary treatment to reduce stroke risk in patients with AF.2,3 However, there is recent evidence of underuse of OAC in AF patients.4 Purpose To identify factors associated with delayed OAC treatment initiation among AF patients in the US clinical practice. Methods Medicare beneficiaries aged ≥65 years with a new diagnosis of AF without moderate-to-severe mitral stenosis or a mechanical heart valve after 1 Oct 2015 were included. Additional inclusion criteria included ≥1 claim for an OAC on or after 1st diagnosis of AF, ≥12 months of continuous Medicare Parts A, and D enrollment, and CHA2DS2-VASc score of ≥2 for males/≥3 for females. Time from 1st AF diagnosis to OAC initiation (index OAC), and demographic, sociodemographic, clinical and index OAC formulary characteristics were described. Delayed initiation was defined as OAC initiation &amp;gt;3 months after and early initiation as OAC initiation 0-3 months after 1st AF diagnosis. Factors associated with delayed OAC initiation were assessed using multivariable logistic regressions. Results A total of 446,441 patients met the inclusion criteria. Time from 1st AF diagnosis to OAC initiation was &amp;lt;1 month for 52.4% of patients, 1–≤3 months for 18.1%, &amp;gt;3–≤6 months for 7.1%, &amp;gt;6–≤12 months for 6.8%, and &amp;gt;12 months for 15.7%. Accordingly, 30% had delayed vs. 70% had early OAC initiation. Median age was 78 years (both), 48% and 47% were male, 87% and 89% were White, and median CHA2DS2-VASc score was 4 (both), respectively, for the delayed and early OAC initiation cohorts (Table 1). Factors associated with delayed OAC initiation included Black race (odds ratio [OR]: 1.29, 95% confidence interval [CI]: 1.25–1.33), South and West US census regions (OR: 1.22, 95%CI: 1.19–1.24 and OR: 1.29, 95%CI: 1.26–1.32, respectively), dementia (OR: 1.27, 95%CI: 1.23–1.30), congestive heart failure (OR: 1.20, 95%CI: 1.26–1.32), bleeding hospitalization ≤3 months before 1st AF diagnosis (OR: 1.22, 95%CI: 1.18–1.27), prior authorization (OR: 1.69, 95%CI: 1.66–1.71), and tier 4 formulary for index OAC at AF diagnosis (OR: 1.26, 95%CI: 1.22–1.30). Additionally, having low-income subsidy or dual eligibility (for Medicare and Medicaid) was associated with increased odds of delayed OAC initiation (OR: 1.06, 95%CI: 1.02–1.10 and OR: 1.09, 95%CI: 1.05–1.14, respectively; Figure 1). Conclusions In this study on Medicare patients with AF, Black race, low-income subsidy, and dual eligibility were found to be associated with delayed OAC initiation, suggesting potential disparities in the care of AF with timely OAC treatment. Moreover, OAC requiring prior authorization (the strongest predictor) or being on formulary tier 4 were associated with delayed initiation, indicating formulary restrictions may create barriers to timely OAC access for AF patients.Table 1.Patient characteristicsFigure 1.Factors of delayed initiation

Atrial fibrillation burden and timing of anticoagulation therapy in patients with screen-detected and clinically-diagnosed AF

Abstract Purpose We evaluated the impact of atrial fibrillation (AF) burden and timing of oral anticoagulation (OAC) therapy initiation on stroke risk in patients with screen-detected and clinically-diagnosed AF. Methods Consecutive patients aged ≥65 years attending medical outpatient clinics with or without known AF were prospectively enrolled for AF-screening using handheld single-lead ECG (AliveCor) from 12/2014 to 12/2017 (NCT02409654). Repeated screening was performed in patients with &amp;gt;1 visit during this period. Patients who participated in repeat screening were included in final analysis. Patients with previously known AF who were in AF in the initial screening and those with repeat screen-positivity were considered probably persistent AF, otherwise paroxysmal AF (single screen-positivity) or no AF (never screen-positive). Time from AF detection to initiation of OAC (Dx-to-Rx) was divided into two exposure levels, Dx-to-Rx ≤ 1 and &amp;gt;1 month. Ischemic stroke risk was estimated using adjusted sub-distribution hazard ratios (aSHR) derived from Fine and Gray regression models, accounting for death as competing risk, adjusting for components of CHA2DS2VASC score and chronic renal disease, with no AF as reference and stratified according to AF burden and Dx-to-Rx. Results Of 11,972 patients enrolled, 3,853(32.2%) received repeated screening (mean age 76.7±7.3, female 47.5%), of which 3.7% (n=144) had screened-detected AF, 25.2% (n=972) previously known AF, 5.9% (n=226) clinically-diagnosed AF during follow-up, and 65.2% (n=2,511) no AF. Persistent AF was identified in 16.7% (n=644/3,853). Of patients with all AF categories, 55.1% (n=739/1,342) initiated OAC within 1 month after AF diagnosis. During a median follow-up period of 7.2(IQR: 6.1-7.5) years, compared to no AF, patients with paroxysmal AF and Dx-to-Rx ≤ 1m (aSHR=1.40, 95%CI:0.80-2.47) had similar low risk of ischemic stroke, while aSHR was highest for persistent AF and Dx-to-Rx &amp;gt;1m (aSHR=2.42, 95%CI:1.38-4.26), followed by persistent AF with Dx-to-Rx≤ 1m (aSHR=2.19,95%:1.47-3.28), and paroxysmal AF with Dx-to-Rx &amp;gt;1m (aSHR=2.00,95%CI:1.32-3.02) (Figure). Subgroup analysis revealed the effect of early initiation of OAC (P for interaction=0.936) and higher AF burden (P for interaction=0. 863) were consistent across screen-detected and clinically-diagnosed AF. Conclusion Among patients with screen-detected AF or clinically-diagnosed AF, lower AF burden and immediate initiation of OAC therapy were associated with reduction in risk of ischemic stroke. Early detection of AF by screening facilitating early OAC prophylaxis might improve clinical outcomes.Cumulative risk of ischemic stroke

The impact on the elapsed time to care and outcomes of a clinician-to-clinician electronic consultation program in patients diagnosed or suspected atrial fibrillation in primary care

Abstract Background An early diagnosis and early initiation of oral anticoagulants (OAC) are main determinants for outcomes in patients with atrial fibrillation (AF). Clinician-to-clinician electronic consultations (e-consultations) program as the first step in the ambulatory care organization for the general practitioner (GPs) referrals to cardiologist may improve health care access by reducing the elapsed time for cardiology care compared with a face-to-face consultation for all the referrals. Objective To evaluate the effect on outcomes of a reduced elapsed time to care after a clinician-to-clinician e-consultations program implementation (2013–2019) in comparison with previous in-person consultation (2010–2012) in the outpatient health care management in a Cardiology Department. Methodology We included 10,488 patients referred by general care practitioners for cardiology consultation with confirmed or suspected AF from 1 January 2010, to 31 December 2019. Until 2012, all patients were attended with an in-person consultation (2010–2012). In 2013, we instituted an e-consult program (2013–2019) for all primary care referrals to cardiologists that preceded patient's in-person consultation when considered. The shared electronic patient dossier (EPD) was available between GP and cardiologist, and any clinical comment and change in therapy advice from cardiologist was directly implemented in this EPD. Results During the e-consultation period (2013–2019) were referred 6627 patients by GPs to cardiology versus 3861 during the in-person consultation (2010– 2012). The e-consultation implementation was associated with a reduction in the elapsed time to anticoagulation prescription (177.6 ±8.9 vs. 22.5 ±8.1 days,p &amp;lt; .001) (Figure 1, A), and an increase of OAC use (61% [95% IC: 19.6%–102.4%], p &amp;lt; .001) (Figure 1, B). The e-consult program implementation was associated with a reduction in the 1-year CV mortality (.48 [95% CI: .30–.75]) and all-cause mortality (.42 [95% CI: .29– .62]). The OAC reduces the stroke mortality (.15 [95% CI: .06–.39]) and CV mortality (.43 [95% CI: .29–.62]) and all-cause mortality (.23 [95% CI: .17–.31]) (Figure 2). Conclusion A shared EPD-based clinician-to-clinician e-consultation program significantly reduced the elapsed time for cardiology consultation and initiation of OAC. The implementation of this program was associated with a lower risk of stroke, cardiovascular and all-cause mortality.