Safety and efficacy of direct oral anticoagulants in geriatric patients with non-valvular atrial fibrillation: A single-center retrospective study

INTRODUCTION

Direct oral anticoagulants (DOACs) are widely employed for antithrombotic prophylaxis in patients with atrial fibrillation (AF). However, there is still uncertainty about their risk-benefit profile in older patients. Here, we evaluated the efficacy, safety, and dose appropriateness of DOACs in a real-world population of outpatients with non-valvular AF, with a specific focus on subjects aged over 80 years and/or with reduced renal function.

MATERIALS AND METHODS

Single-center retrospective study including patients who had been prescribed a DOAC between May 2014 and May 2021 for long-term anticoagulation in non-valvular AF. Patients anticoagulated for <4 weeks were excluded. The primary efficacy outcome was a composite of cardiovascular (CV) death, stroke, or systemic embolism. The primary safety outcome was major bleeding.

RESULTS

A total of 1154 patients (median age 84 yrs., range 57-100 yrs.), among which 862 were 80 years and older, were included. In the subgroup of subjects ≥80 yrs., a subtherapeutic dose of DOAC was associated with an increased incidence of CV mortality, stroke, or systemic embolism (multivariable Cox regression, HR = 2.09, 95 % CI: 1.09-4.02), with no benefit in terms of prevalence of bleeding events (21.5 % vs. 18.6 %, p = 0.428), and the incidence of adverse safety and efficacy outcomes was not increased in patients with a reduced renal function (eGFR ≤30 mL/min). Plasma concentration of DOACs, assessed in a subset of 367 patients, did not increase with advanced age (≥ 80 yrs., two-way ANOVA, p = 0.656) nor with declining eGFR (≤30 mL/min, two-way ANOVA, p = 0.643) and was not associated with adverse safety and efficacy outcomes.

CONCLUSIONS

Data from our study support the use of DOACs in populations of older adults and remark on the risks associated with inappropriate prescriptions in terms of CV mortality and adverse events.

Direct oral anticoagulants for patients aged over 80 years in nonvalvular atrial fibrillation: the impact of frailty

AIMS

In patients aged at least 80 years, atrial fibrillation is responsible for significant morbidity and mortality, with a high incidence of stroke. Four new direct oral anticoagulants (DOACs) have been introduced in Italy for the prevention of thromboembolism. Their safety and efficacy in the elderly have already been confirmed. Frailty is frequently associated with aging, but only a few studies have paid attention to interactions between frailty and anticoagulation therapy.

METHODS

We retrospectively evaluated the effectiveness and safety of DOACs in a population aged at least 80 years. Frailty was appraised using an adaptation of the Reported Edmonton Frail Scale, considering a value at least 8 (on a scale from 0 to 18).

RESULTS

The majority (644/731) of patients remained on DOACs for more than 1 year. A total of 19 patients experienced a thrombotic event while on anticoagulation (1.11 events per 100 person-years) and 26 patients a major bleeding episode (1.52 events per 100 person-years). The probability of interrupting therapy increased significantly with frailty [hazard ratio 2.91 with confidence interval (CI) 2.15-3.92 at univariate analysis, hazard ratio 2.80 with CI 2.03-3.86 at multivariate]; frailty showed a significant impact also on major bleeding (hazard ratio 3.28 with CI 1.45-7.37 at univariate analysis, hazard ratio 3.56 with CI 1.58-8.01 at multivariate).

CONCLUSION

Our study highlights how DOACs are a safe and effective option for anticoagulation, even in frail elderly people; the introduction of these drugs is leading to an increased use of anticoagulation therapy in this population. Prospective trials will be needed to reinforce these results and to consider new variables in the thrombotic and hemorrhagic risk scores underlying the prescription of DOACs.

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

OBJECTIVES

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

DESIGN

This study was a systematic review.

DATA SOURCES

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

ELIGIBILITY CRITERIA

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

DATA EXTRACTION AND SYNTHESIS

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

RESULTS

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

CONCLUSION

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

Net Clinical Benefit of Non-Vitamin K Antagonist vs Vitamin K Antagonist Anticoagulants in Elderly Patients with Atrial Fibrillation

BACKGROUND

The risks of thromboembolic and hemorrhagic events in patients with atrial fibrillation both increase with age; therefore, net clinical benefit analyses of anticoagulant treatments in the elderly population are crucial to guide treatment. We evaluated the 1-year clinical outcomes with non-vitamin-K antagonist and vitamin K antagonist oral anticoagulants (NOACs vs VKAs) in elderly (≥75 years) patients with atrial fibrillation in a prospective registry setting.

METHODS

Data on 3825 elderly patients were pooled from the PREFER in AF and PREFER in AF PROLONGATION registries. The primary outcome was the incidence of the net composite endpoint, including major bleeding and ischemic cardiovascular events on NOACs (n = 1556) compared with VKAs (n = 2269).

RESULTS

The rates of the net composite endpoint were 6.6%/year with NOACs vs 9.1%/year with VKAs (odds ratio [OR] 0.71; 95% confidence interval [CI], 0.51-0.99; P = .042). NOAC therapy was associated with a lower rate of major bleeding compared with VKA use (OR 0.58; 95% CI, 0.38-0.90; P = .013). Ischemic events were nominally reduced too (OR 0.71; 95% CI, 0.51-1.00; P = .050). Major bleeding with NOACs was numerically lower in higher-risk patients with low body mass index (BMI; OR 0.50; 95% CI, 0.22-1.12; P = .07) or with age ≥85 years (OR 0.44; 95% CI, 0.13-1.49; P = .17).

CONCLUSIONS

Our real-world data indicate that, compared with VKAs, NOAC use is associated with a better net clinical benefit in elderly patients with atrial fibrillation, primarily due to lower rates of major bleeding. Major bleeding with NOACs was numerically lower also in higher-risk patients with low BMI or age ≥85 years.

Meta-Analysis of Effectiveness and Safety of Oral Anticoagulants in Atrial Fibrillation With Focus on Apixaban

We performed a meta-analysis of data on the effectiveness and safety of apixaban compared with other oral anticoagulants (warfarin or rivaroxaban or dabigatran or edoxaban) for stroke prevention in atrial fibrillation (AF) in different settings of randomized controlled trials, real-world studies, and radiofrequency ablation (RFA). Thirty studies were searched in PubMed, the Cochrane Library, and Clinicaltrials.gov databases reporting comparative effectiveness and safety of apixaban with warfarin (n = 23), rivaroxaban (n = 12), dabigatran (n = 13), or edoxaban (n = 2) for stroke prevention in AF. In real-world estimates, apixaban was similar to warfarin for the prevention of stroke or systematic thromboembolism (hazard ratio 0.93, 95% CI 0.71 to 1.14, I² = 82.9%, N = 7), and safer than warfarin in the risks of major bleeding (hazard ratio 0.62, 95% CI 0.54 to 0.70, I² = 18.7%, N = 9) in patients with AF. The risk of stroke or thromboembolism with apixaban was similar to rivaroxaban, dabigatran, and edoxaban in the settings of real-world studies and RFA. Major bleeding with apixaban was generally lower than rivaroxaban (relative risks 0.45, 95% CI 0.38 to 0.53, I² = 0%, N = 5) and similar to dabigatran in real-world studies (relative risks 1.44, 95% CI 0.33 to 6.30, I² = 97.7%, N = 5), but similar to rivaroxaban, dabigatran, and edoxaban in RFA. In conclusion, our meta-analysis provides a comprehensive estimate of the effectiveness and safety of apixaban compared with other oral anticoagulants (warfarin, rivaroxaban, dabigatran, and edoxaban) in patients with AF in different settings of randomized controlled trial, real-world studies, and RFA.

Direct oral anticoagulant use and the incidence of bleeding in the very elderly with atrial fibrillation

Atrial fibrillation (AF) is a major risk factor for stroke in the elderly population. The use of anticoagulation in patients with AF greatly reduces the risk for stroke, but results in an increased risk of bleeding. Over the past several years, direct oral anticoagulants (DOACs, dabigatran, rivaroxaban, and apixaban) have been used in place of warfarin for stroke prevention in AF. We conducted a retrospective cohort study to assess the safety of DOACs in very elderly patients (75+) managed in a health care system encompassing both community and academic settings. We found that 36 % of patients had moderate to severe renal failure (estimated glomerular filtration rate <59 ml/min/1.73 m(2)) at the time of DOAC initiation. 142 patients were followed for a mean of 2.56 years, and five experienced a major bleeding episode while on anticoagulation, for a rate of 1.37 per 100 person years. All major bleeding episodes were associated with a decline in GFR compared to baseline. There were 12 non-major bleeding episodes reported. HAS-BLED scores were similar for those patients who experienced bleeding complications compared to those who did not. 21 % of patients were prescribed an inappropriately low dose of DOAC based on approved recommendations. DOACs appear to be a safe form of anticoagulation in very elderly patients with AF. However, the decline in GFR among patients with major bleeding highlights the importance of routine renal function monitoring.