Poor adherence to guideline-directed anticoagulation in elderly Chinese patients with atrial fibrillation: a report from the Optimal Thromboprophylaxis in Elderly Chinese Patients with Atrial Fibrillation (ChiOTEAF) registry

Characteristics and outcome of patients with left atrial appendage closure in China: a single-center experience

BACKGROUND

Clinical characteristics and long-term data on the safety and efficacy of LAAC in preventing cerebrovascular accident and thromboembolism among Chinese patients with non-valvular AF (NVAF) remain limited.

METHODS

Data of consecutive NVAF patients who underwent LAAC at Beijing Anzhen Hospital, Capital Medical University, from June 1, 2014, to December 31, 2021, were collected and analyzed retrospectively. The primary effectiveness endpoint was the composite endpoint of stroke/transient ischemic attack, systemic embolism, and death from cardiovascular causes. The primary safety endpoint is the severe bleeding defined by the LAAC Munich consensus.

RESULTS

Of the 222 patients enrolled, the mean age was 66.90 ± 9.62 years, with a majority being male (77.03%). Many patients are non-paroxysmal AF (71.19%) with a median duration of AF of 4.00 years. The mean CHA2DS2-VASc score was 3.78 ± 1.49, and the mean HAS-BLED score was 1.68 ± 0.86. Thromboembolic events (76.58%) were the most common indication for LAAC. The device, technical, and procedural success rates were 98.65%, 98.65%, and 93.69%, respectively. The anticoagulation continuation rate was 56.36%, 31.25%, and 22.60% at 3-, 6- and 12 months post-procedure, respectively. Throughout a mean 2.81 years of follow-up, the incidence of the primary efficacy endpoint was 4.27 per 100 patient-years, predominantly attributable to stroke/TIA (3.12 per 100 PYs). Five patients experienced major bleeding during the follow-up period. Post-procedure imaging revealed minimal complications, with only one substantial peri-device leak. Device-related thrombus occurred in 2.33% of patients, resolving with anticoagulation.

CONCLUSION

The study demonstrates that LAAC is a safe and effective alternative option for Chinese patients with AF, with a high success rate, few complications as well as fewer long-term adverse outcome events.

Implications of Clinical Risk Phenotypes on the Management and Natural History of Atrial Fibrillation: A Report From the GLORIA-AF

Background Clinical risk factors are common among patients with atrial fibrillation (AF), but there are still limited data on their association with oral anticoagulant (OAC) treatment patterns and major outcomes. We aim to analyze the association between clinical risk phenotypes on AF treatment patterns and the risk of major outcomes. Methods and Results The GLORIA-AF (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients With Atrial Fibrillation) phase 2 and 3 registries enrolled patients with a recent diagnosis of AF between 2011 and 2016. We defined 4 features of clinical risk among patients with CHA2DS2-VASc ≥2: elderly individuals (aged ≥80 years), chronic kidney disease (estimated glomerular filtration rate <45 mL/min), history of stroke, and history of bleeding. We analyzed the odds of receiving OAC and the risk of OAC discontinuation and adverse events at follow-up according to specific combinations and cumulative burden of these features. Primary outcome was the composite of all-cause death, thromboembolism, and major bleeding. Among 28 891 (mean±SD age, 70.1±10.5 years; 45.5% women) patients included, 10 797 (37.3%) had at least 1 clinical risk feature. OAC use was lower among patients in the elderly group (odds ratio [OR], 0.85 [95% CI, 0.75-0.96]), those with history of both stroke and bleeding (OR, 0.45 [95% CI, 0.35-0.56]), and those with multiple features (OR, 0.71 [95% CI, 0.62-0.82]). Increasing burden of clinical risk features was associated with OAC discontinuation, with highest magnitude in those with ≥3 features (hazard ratio [HR], 1.68 [95% CI, 1.31-2.15]). Groups with increasingly complex clinical risk phenotypes were associated with the occurrence of the primary composite outcome, with the highest figures observed for groups with a history of both stroke and bleeding (adjusted HR, 2.36 [95% CI, 1.83-3.04]) and multiple features (adjusted HR, 2.86 [95% CI, 2.52-3.25]). Conclusions In patients with AF, clinical risk phenotypes are multifaceted and heterogenous, and they are associated with differences in stroke prevention and worse prognosis.

Clinical benefits of oral anticoagulants in atrial fibrillation patients with dementia: a systematic review and meta-analysis

Background

The management of atrial fibrillation (AF) with oral anticoagulants (OAC) is generally recommended to reduce the risk of stroke. However, the decision to prescribe these medications for patients with AF and dementia remains controversial.

Methods

A systematic review and meta-analysis of retrospective cohort studies were conducted. The search encompassed PubMed, Cochrane Library, Web of Science, and Embase databases from inception until May 1st, 2023, with language limited to English. Eligible studies included comparisons between exposure to OAC vs. non-OAC in the AF population with dementia or cognitive impairment. Studies that compared the effects of direct oral anticoagulants (DOAC) and vitamin-K antagonists were also included. The primary outcome was all-cause mortality, and the secondary outcomes were ischemic stroke and major bleeding. This study was registered with PROSPERO (No. CRD42023420678).

Results

A total of five studies (N = 21,962 patients) met the eligibility criteria and were included in this review. The follow-up duration ranged from 1 to 4 years. Meta-analysis demonstrated that OAC treatment was associated with a lower risk of all-cause mortality in AF patients with dementia with a hazard ratio (HR) of 0.79 and a 95% confidence interval (CI) ranging from 0.68 to 0.92, compared to non-OAC treatment. No statistical differences were observed in the risk of major bleeding (HR = 1.12, 95% CI: 0.88-1.42) or ischemic stroke (HR = 0.77, 95% CI: 0.58-1.00). Three studies reported comparisons between DOAC and warfarin; however, pooled analysis was not performed due to heterogeneity.

Conclusion

The use of OACs in individuals diagnosed with both AF and dementia holds the potential to reduce all-cause mortality rates, thereby improving the overall clinical prognosis within this specific population.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023420678, PROSPERO identifier, CRD42023420678.

Management and Anticoagulation Treatment of Non-Valvular Atrial Fibrillation in Elderly Patients: The Dali Study

Background

Non-valvular atrial fibrillation (NVAF) is associated with increased stroke in elderly populations, yet anticoagulant therapy is underutilized. We analyzed clinical characteristics and anticoagulation treatment rates of elderly NVAF patients hospitalized in Dali, China, to identify potential contributing factors.

Methods

We collected data for 155 elderly patients with NVAF aged ≥60 years, from July 01, 2020, to December 31, 2021. We analyzed the awareness rate, clinical characteristics, and anticoagulant treatment rate of atrial fibrillation (AF), and identified factors influencing treatment. Patients were followed up one year after discharge to assess vital status, cardiovascular events, and anticoagulation therapy status.

Results

Among 155 patients, 52.26% were female, and the average age was 75.77 years. The awareness rate of AF was 47.74% at admission, and only 21.94% received anticoagulant therapy. After discharge, the rate of anticoagulant therapy significantly increased to 70.97%, and 89.09% used new oral anticoagulants. Thromboembolic history and persistent AF predicted anticoagulant therapy at discharge, while male gender, previous bleeding history, and antiplatelet therapy predicted non-anticoagulant therapy. Out of 133 patients who completed a one-year follow-up, 23.31% died, 3.01% had strokes, and 3.01% experienced bleeding. Anticoagulant therapy decreased to 51.96% during the follow-up year.

Conclusion

Our findings highlight the low awareness rate and anticoagulant treatment rate, and high mortality among elderly NVAF patients in Dali. The development of comprehensive intervention strategies is critical to standardize AF management and improve prognosis.

Real world time trends in antithrombotic treatment for newly diagnosed atrial fibrillation in China: reports from the GLORIA-AF Phase III registry : Trends in antithrombotic therapy use in China

BACKGROUND

Stroke prevention with oral anticoagulant (OAC) therapy, including non-vitamin K antagonist oral anticoagulants (NOACs), is recommended in patients with atrial fibrillation (AF). This analysis describes the antithrombotic prescription patterns for Chinese patients enrolled post-dabigatran approval during Phase II and III of the Global Registry on Long-Term Oral Antithrombotic Treatment in Patients with Atrial Fibrillation (GLORIA-AF) program in China.

METHODS

Patients aged ≥ 18 years with newly diagnosed (< 3 months before baseline visit) nonvalvular AF at risk of stroke (CHA₂DS₂-VASc score ≥ 1) were consecutively enrolled in the GLORIA-AF registry. This cross-sectional analysis provides descriptive comparison of Chinese patients in Phase III (2015-2016) with those enrolled in Phase II (2013-2014).

RESULTS

Overall, 1,018 and 1,911 Chinese patients were eligible for analysis in Phase II and III, respectively. Most patients (69.6% and 69.1%, respectively) had high stroke risk (CHA₂DS₂-VASc score ≥ 2 for males and ≥ 3 for females). High bleeding risk (HAS-BLED score ≥ 3) rates were similar (17.3% for Phase II, 17.6% for Phase III). In Phase II, 5.8%, 15.2%, 36.7% and 42.2% of patients were prescribed NOACs, vitamin K antagonists (VKAs), antiplatelet therapies or no antithrombotic treatment, respectively. The corresponding figures were 17.2%, 23.5%, 37.4% and 21.8% for patients in Phase III, with an overall increase in OAC prescriptions (NOACs or VKAs). In patients with high stroke risk, the prescription patterns in Phase II were 5.6%, 14.4%, 41.0% and 38.9% for NOACs, VKAs, antiplatelets or no antithrombotic treatment, respectively. The respective proportions in Phase III were 15.1%, 23.5%, 40.9% and 20.5%.

CONCLUSIONS

Since the availability of dabigatran in China, the overall trend of OAC, including NOAC, prescriptions in Chinese patients with nonvalvular AF has increased over time, albeit with VKAs as the most common antithrombotic treatment. Most patients, including those at high stroke risk, remain undertreated according to best practice guidelines.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01468701.

Edoxaban treatment in atrial fibrillation in routine clinical care: One-year outcomes of the prospective observational ETNA-AF study in South Korean patients

BACKGROUND

The real-world outcomes of edoxaban treatment in patients with atrial fibrillation (AF) were analyzed in the ETNA-AF (Edoxaban Treatment in Routine Clinical Practice) study involving data from multiple regional registries. This report addresses effectiveness and safety of edoxaban in the Korean ETNA-AF population.

METHODS

One-year data from 1887 Korean ETNA-AF participants were analyzed according to edoxaban dose and patient age and compared with results of other ETNA-AF registries.

RESULTS

Approximately 70% of patients received the recommended doses of edoxaban (60 mg/30 mg); non-recommended 60 mg and 30 mg doses were prescribed to 9.6% and 19.8% of the patients, respectively. The proportions of reference age (<65 years), youngest-old (65-74 years) and middle-old/oldest-old (≥75 years) groups were 21.4%, 40.2%, and 38.4%, respectively. Incidence of major or clinically relevant nonmajor bleeding was similar within dose (0.57%-1.71%) and age subgroups (1.26%-1.63%). Incidence of net clinical outcome, a composite of stroke, systemic embolic event, major bleeding, and all-cause mortality, was also comparable among dose subgroups (1.14%-3.10%) and age subgroups (2.28%-2.78%). The percentage of Korean patients receiving non-recommended 30 mg (19.8%) was over twice that of the European population (8.4%). However, the clinical outcomes were generally similar among different populations included in the ETNA-AF study.

CONCLUSIONS

The outcomes in the Korean ETNA-AF population are like those in the global ETNA-AF population, with overall low event rates of stroke, major bleeding and all-cause mortality across age and dose subgroups. Edoxaban can be used effectively and safely in specific populations of Korean AF patients, including the elderly.

Correct dosing, adherence and persistence of DOACs in atrial fibrillation and chronic kidney disease: a systematic review and meta-analysis

BACKGROUND

Chronic kidney disease (CKD) and atrial fibrillation (AF) are increasing in prevalence globally and share common risk factors.Our aim was to characterise real-world evidence on direct oral anticoagulant (DOAC) prescribing for people with AF and CKD, in terms of adherence, persistence and renal dose titration.

METHODS

PubMed, EMBASE and CINAHL were searched from inception to June 2022. Our search terms included a combination of Medical Subject Headings (MeSH) terms and keywords including 'atrial fibrillation', 'chronic kidney disease', 'adherence', 'persistence', 'direct oral anticoagulants' and 'dosing'. Data extraction and quality assessment were undertaken by two reviewers independently. Meta-analyses for pooled estimates were performed using DerSimonian and Laird random-effects models. Age, sex, diabetes, hypertension and heart failure were chosen as variables of interest.

RESULTS

From 19 studies, a total of 252 117 patients were included with CKD and AF. Meta-analysis was only possible in seven studies with 128 406 patients, five on DOAC dose titration and two on adherence. There were insufficient studies on persistence. Our meta-analysis of dosing showed that 68% of patients with CKD and AF had correct dosing. There was no evidence to show any association between correct DOAC dosing and variables of interest. Overall, 67% of patients were DOAC adherent.

CONCLUSION

Adherence and correct dosing of DOACs were suboptimal compared with other medications in the pooled studies with respect to CKD and AF. Thus, further research is required as the lack of generalisation of findings is a rate-limiting factor for improved DOAC management in AF and CKD.

PROSPERO REGISTRATION NUMBER

CRD;42022344491.

Efficacy and safety of oral anticoagulants in elderly patients with stable coronary artery disease and atrial fibrillation

Background

This study aimed to evaluate the efficacy and safety of oral anticoagulants (OACs) in real-world elderly patients with comorbidities of stable coronary artery disease (SCAD) and atrial fibrillation (AF).

Methods

Elderly patients (aged ≥ 65 years old) diagnosed with SCAD and AF were consecutively recruited and grouped into patients with or without oral anticoagulant (OAC) treatment. Follow-up was performed for 5 years. Major adverse cardiac events (MACEs) were defined as a composite of all-cause death, nonfatal myocardial infarction (MI), nonfatal stroke, and systemic embolism. Major bleeding outcomes were defined as events that were type ≥ 3 based on the Bleeding Academic Research Consortium (BARC) criteria. The net clinical outcomes were defined as the combination of MACEs and bleeding of BARC type ≥ 3.

Results

A cohort of 832 eligible patients (78 ± 6.70 years) was included. Compared to the patients without OAC treatment (n = 531, 63.82%), the patients treated with OAC (n = 301, 36.18%) were much younger, had higher body mass index (BMI), and had lower prevalence of heart failure, chronic obstructive pulmonary disease (COPD), renal insufficiency, and previous myocardial infarction. During the follow-up of 5 years, compared to the patients without OAC treatment, patients with OAC had a significantly lower risk of MACEs (20.60% vs. 58.95%, adjusted HR: 0.21, 95% CI: 0.15–0.30, p < 0.001) but a higher risk of BARC ≥ 3 bleeding events (4.65% vs. 1.32%, adjusted HR: 4.71, 95% CI: 1.75–12.64, p = 0.002). In combination, a lower risk of net clinical outcomes could be observed in the patients with OACs (23.26% vs. 58.96%, adjusted HR: 0.27, 95% CI: 0.19–0.38, p < 0.001). Among the patients with OAC treatment, no significant difference was found for MACEs or BARC ≥ 3 bleeding events between the patients with or without comedications of oral antiplatelet agents.

Conclusions

A net clinical benefit of efficacy and safety could be observed in OAC-treated elderly patients with SCAD and AF. This benefit is independent of the comedications of oral antiplatelet treatment.

Screening for Atrial Fibrillation by Village Doctors in Rural Areas of China: The Jiangsu Province Rural Community AF Project

China has a large population of elderly in rural areas. Village doctors are acting as health-care gatekeepers for the rural elderly in China and are encouraged to provide more long-term care for patients with chronic diseases such as atrial fibrillation (AF). The data of AF registries from the rural elderly are limited. The present registry aims to provide contemporary data on the current AF-related health status of the rural elderly and the gaps in management of AF by village doctors. This study has two phases. The first phase is a cross-sectional study of AF screening in two rural towns of eastern China. All the residents aged ≥65 years are eligible and will be invited to attend a government-led health examination or an in-house AF screening program. The AF detection rate, the awareness of AF and the usage of oral anticoagulants and smartphones by AF patients, and the ability to diagnose and manage AF by village doctors will be assessed. Participants with AF detected in the first phase are eligible for the second phase. A variety of modes of intensified education will be provided to all AF patients and their family members to enrich their AF-related knowledge. Their village doctors will be offered a lecture-based training program focusing on Atrial fibrillation Better Care (ABC) pathway. Follow-up will be conducted for 1 year. The primary endpoint is the composite of all stroke and all-cause mortality. The first phase of AF screening was conducted between April 2019 and June 2019, and 18,712 participants with the mean age of 73.1±5.8 years were enrolled. The second phase that includes 810 patients with AF, started on 1 May 2019. This study will provide a perspective of primary care system and would indirectly reflect the current status of chronic disease care in rural China.

Efficacy and Safety of Antithrombotic Therapy With Oral Anticoagulants in Real-World Elderly Patients With Acute Coronary Syndrome and Atrial Fibrillation

Background

The efficacy and safety of antithrombotic treatment with oral anticoagulants (OACs) in elderly patients with comorbidities of acute coronary syndrome (ACS) and atrial fibrillation (AF) are unclear.

Methods

A cohort of hospitalized elderly patients (≥65 years of age) diagnosed with ACS and AF and treated with oral antithrombotic agents were consecutively recruited. Follow-up was performed for at least 1 year. Major adverse cardiac events (MACEs) were defined as a composite of all-cause death, nonfatal myocardial infarction (MI), nonfatal stroke, and systemic embolism. The safety outcomes of bleeding were defined according to the Bleeding Academic Research Consortium (BARC) criteria.

Results

A cohort of 548 eligible patients (76 ± 6.6 years) was analyzed. Compared to the patients with OAC treatment (n = 184, 33.6%), patients treated without OAC (n = 364, 66.4%) were older, had a lower prevalence of persistent AF and unstable angina (UA), and more often presented with paroxysmal AF, acute myocardial infarction (AMI), stent implantation and dual antiplatelet therapy (DAPT). Compared to the patients without OAC treatment (n = 364, 66.4%), patients treated with OAC (n = 184, 33.6%) had a lower risk of MACEs at both the 1-year (4.3 vs. 15.1%, adjusted HR: 0.34, 95% CI: 0.15–0.80, p = 0.014) and 5-year (17.5 vs. 48.4%, adjusted HR: 0.36, 95% CI: 0.19–0.67, p = 0.001) follow-up. No significant difference was observed for bleeding events of BARC ≥2 between the groups (8.0 vs. 9.0%, adjusted HR: 1.17, 95% CI: 0.58–2.34, p = 0.667). Compared with warfarin-treated patients, the non-vitamin K antagonist oral anticoagulant-treated patients had lower risks of all-cause mortality (2.1 vs. 9.5%, HR: 0.18, 95% CI: 0.03–0.98, p = 0.047) and bleeding events of BARC ≥ 3 (2.1 vs. 4.8%, HR: 0.14, 95% CI: 0.02–1.10, p = 0.062).

Conclusions

Antithrombotic therapy with OACs in elderly patients with ACS and AF was associated with a lower risk of ischemic events without an increase in bleeding events. In real-world practice, the clinical awareness of anticoagulation treatments in elderly patients with ACS and AF needs to be strengthened.

Outcomes in elderly Chinese patients with atrial fibrillation and coronary artery disease. A report from the Optimal Thromboprophylaxis in Elderly Chinese Patients with Atrial Fibrillation ( ChiOTEAF ) registry

Background

Atrial fibrillation (AF) and coronary artery disease (CAD) are closely related; CAD may precede or complicate the clinical course of AF.

Objective

To evaluate the impact of CAD on clinical outcomes among elderly Chinese AF patients.

Methods

The ChiOTEAF registry is a prospective registry conducted in 44 sites from 20 provinces in China between October 2014 and December 2018. Primary outcome was the composite of all‐cause mortality/any thromboembolism (TE)/major bleeding/acute coronary syndrome (ACS).

Results

The eligible cohort for this analysis included 6403 individuals (mean age 74.8 ± 10.7; 39.2% female); of these, 3058 (47.8%) had a history of CAD. On multivariate analysis, CAD was independently associated with a higher odds ratio for ACS (OR: 1.98; 95% CI: 1.12–3.52) without a significant impact on other adverse outcomes. Independent variables associated with the composite outcome among CAD patients were: (i) the use of OAC (OR: 0.55; 95% CI: 0.42–0.72), age (OR: 1.09; 95% CI: 1.08–1.11), heart failure (OR: 1.95; 95% CI: 1.51–2.50), prior ischemic stroke (OR: 1.29; 95% CI: 1.02–1.64), chronic kidney disease (OR: 1.71; 95% CI: 1.32–2.22), and chronic obstructive pulmonary disease (OR: 1.42; 95% CI: 1.06–1.89).

Conclusions

AF patients with CAD were at an increased risk of developing ACS but there was no significant difference in the composite outcome, all cause death, cardiovascular death, thromboembolic events or major bleeding compared to the non‐CAD group. OAC use was inversely associated with adverse events, yet their uptake was poor in the AF‐CAD population.

Impact of Multimorbidity and Polypharmacy on Clinical Outcomes of Elderly Chinese Patients with Atrial Fibrillation

Background: The co-incidence of multiple morbidities and polypharmacy is common amongst patients with atrial fibrillation (AF); however, data on their impact on clinical outcomes are scarce in Asian cohorts. Objective: To evaluate the impact of multimorbidity and polypharmacy on clinical outcomes and AF management among elderly Chinese patients. Methods: The ChiOTEAF registry is a prospective, multicenter nationwide study conducted from October 2014 to December 2018. Endpoints of interest were the composite outcome of all-cause death/any thromboembolism (TE), all-cause death, cardiovascular death, TE events, major bleeding, as well as AF management. Results: The eligible cohort included 6341 individuals (mean age 74.7 ± 10.7; 39.1% female), of whom 4644 (73.2%) had multimorbidity (defined as two or more chronic diseases), and 2262 (35.7%) were treated with five or more medications. There were 2775 (43.8%) patients on anticoagulant (OAC) use. On multivariate analysis, (i) multimorbidity was associated with a higher odds ratio of the composite outcome (OR: 2.04; 95% CI: 1.49–2.79), all-cause death (OR: 1.82; 95% CI: 1.31–2.54), cardiovascular death (OR: 2.05; 95% CI: 1.13–3.69), any TE (OR: 2.69; 95% CI: 1.29–5.62), and major bleeding (OR: 2.61; 95% CI: 1.25–5.45); (ii) polypharmacy was associated with a lower odds ratio of all-cause death (OR: 0.78; 95% CI: 0.63–0.96). The use of OAC was safe and was associated with a lower odds ratio of the composite outcome and all-cause death in all subgroups of patients. Conclusions: Multimorbidity and polypharmacy were common among elderly AF Chinese patients. Multimorbidity was an independent predictor of adverse clinical outcomes. The use of OAC was safe and significantly improved survival amongst AF patients with multimorbidity and polypharmacy.

Clinical Events with Edoxaban in South Korean and Taiwanese Atrial Fibrillation Patients in Routine Clinical Practice

Edoxaban is approved for stroke prevention in nonvalvular atrial fibrillation (AF) patients in numerous countries. Outcome data are sparse on edoxaban treatment in AF patients from routine clinical practice, especially in Asian patients. Global ETNA (Edoxaban in rouTine cliNical prActice) is a noninterventional study that integrates data from patients from multiple regional registries into one database. Here, we report the 1-year clinical events from AF patients receiving edoxaban in South Korea and Taiwan. Clinical events assessed included bleeding, strokes, systemic embolic events, transient ischemic attacks (TIAs), and all-cause and cardiovascular death. Overall, 2677 patients (mean (range) age 72 (66–78) years, male 59.7%, mean CHA₂DS₂-VASc score ± standard deviation 3.1 ± 1.4) were treated with 60 or 30 mg edoxaban and had 1-year follow-up data. The annualized event rates for major bleeding and clinically relevant non-major (CRNM) bleeding were 0.78% and 0.47%, respectively. Annualized event rates for ischemic stroke and hemorrhagic stroke were 0.90% and 0.19%, respectively. Event rates for major and CRNM bleeding and rates of ischemic stroke and TIA were higher in Taiwanese patients than in Korean patients. Event rates were low and similar to those found in other studies of edoxaban in Korean and Taiwanese AF patients, thus supporting the safety and effectiveness of edoxaban in this population.

Are low doses of non-vitamin K antagonists effective in Chinese patients with atrial fibrillation? A report from the Optimal Thromboprophylaxis in Elderly Chinese Patients with Atrial Fibrillation (ChiOTEAF) registry

BACKGROUND

Suboptimal low dosages of non-vitamin K antagonist oral anticoagulants (NOACs) are often inappropriately used due to a fear of bleeding, particularly among elderly patients. Such practice is common in Asia, and we aimed to evaluate the use of low-dose NOACs and their impact on clinical outcomes among Chinese patients with atrial fibrillation.

METHODS

The Optimal Thromboprophylaxis in Elderly Chinese Patients with Atrial Fibrillation (ChiOTEAF) registry was a prospective, multicenter study conducted in China from October 2014 to December 2018. For this report, we included NOAC-treated patients with available data on NOAC dosage and one-year follow-up. Logistic regression analysis assessed the association (adjusted for age, sex, prior ischemic stroke, prior major bleeding, heart failure, coronary artery disease, hypertension, diabetes mellitus, chronic kidney disease, liver disease, current anemia) between the low doses and study outcomes among NOAC-treated patients, as well as comparisons with non-anticoagulated patients.

RESULTS

The eligible cohort included 1310 NOAC-treated patients (mean age of 72.1 ± 10.9; 38.9% female), of whom 341 (26.0%) received a low "off-label" dose. The use of low-dose NOACs was independently associated with higher odds of the composite outcome (OR: 2.51; 95% CI: 1.11-5.71) and thromboembolism (OR: 4.73; 95% CI: 1.11-20.01). Compared with non-anticoagulated patients, lower rates of the composite outcome (7.3% vs. 11.3%; p = 0.025) and all-cause death (5.3% vs. 9.7%; p = 0.007) were seen in the low-dose group (ORs 0.50; 95% CI: 0.32-0.78, and 0.42; 95% CI: 0.26-0.70, respectively).

CONCLUSIONS

Low doses of NOACs should not be recommended as a part of standard therapy among Chinese patients with atrial fibrillation as their use was associated with a higher odds ratio of the composite outcome and thromboembolic events compared with standard dose NOAC regimens. Compared to non-treatment, the use of low-dose NOAC may result in a survival benefit (but not thromboembolic reduction) among high-risk patients.