Reply: Apixaban Dosing in Chronic Kidney Disease: Differences Between U.S. and E.U. Labeling

Associations of Apixaban Dose With Safety and Effectiveness Outcomes in Patients With Atrial Fibrillation and Severe Chronic Kidney Disease

BACKGROUND

Recommendations for apixaban dosing on the basis of kidney function are inconsistent between the US Food and Drug Administration and European Medicines Agency for patients with atrial fibrillation. Optimal apixaban dosing in chronic kidney disease remains unknown.

METHODS

With the use of deidentified electronic health record data from the Optum Labs Data Warehouse, patients with atrial fibrillation and chronic kidney disease stage 4/5 initiating apixaban between 2013 and 2021 were identified. Risks of bleeding and stroke/systemic embolism were compared by apixaban dose (5 versus 2.5 mg), adjusted for baseline characteristics by the inverse probability of treatment weighting. The Fine-Gray subdistribution hazard model was used to account for the competing risk of death. Cox regression was used to examine risk of death by apixaban dose.

RESULTS

Among 4313 apixaban new users, 1705 (40%) received 5 mg and 2608 (60%) received 2.5 mg. Patients treated with 5 mg apixaban were younger (mean age, 72 versus 80 years), with greater weight (95 versus 80 kg) and higher serum creatinine (2.7 versus 2.5 mg/dL). Mean estimated glomerular filtration rate was not different between the groups (24 versus 24 mL·min-1·1.73 m-2). In inverse probability of treatment weighting analysis, apixaban 5 mg was associated with a higher risk of bleeding (incidence rate 4.9 versus 2.9 events per 100 person-years; incidence rate difference, 2.0 [95% CI, 0.6-3.4] events per 100 person-years; subdistribution hazard ratio, 1.63 [95% CI, 1.04-2.54]). There was no difference between apixaban 5 mg and 2.5 mg groups in the risk of stroke/systemic embolism (3.3 versus 3.0 events per 100 person-years; incidence rate difference, 0.2 [95% CI, -1.0 to 1.4] events per 100 person-years; subdistribution hazard ratio, 1.01 [95% CI, 0.59-1.73]), or death (9.9 versus 9.4 events per 100 person-years; incidence rate difference, 0.5 [95% CI, -1.6 to 2.6] events per 100 person-years; hazard ratio, 1.03 [95% CI, 0.77-1.38]).

CONCLUSIONS

Compared with 2.5 mg, use of 5 mg apixaban was associated with a higher risk of bleeding in patients with atrial fibrillation and severe chronic kidney disease, with no difference in the risk of stroke/systemic embolism or death, supporting the apixaban dosing recommendations on the basis of kidney function by the European Medicines Agency, which differ from those issued by the US Food and Drug Administration.

Use and Prescription of Direct Oral Anticoagulants in Older and Frail Patients with Atrial Fibrillation: A Multidisciplinary Consensus Document

In the last twelve years the clinical management of patients with atrial fibrillation has been revolutionised by the introduction of direct oral anticoagulants. Despite the large amount of evidence produced, some populations remain relatively poorly explored regarding the effectiveness and safety of direct oral anticoagulants, such as the oldest and/or frailest individuals. Frailty is clinical syndrome characterized by a reduction of functions and physiological reserves which results in individuals having higher vulnerability. While current evidence underlines a relationship between atrial fibrillation and frailty, particularly in determining a higher risk of adverse outcomes, data regarding effectiveness and safety of direct oral anticoagulants in frailty atrial fibrillation patients are still lacking, leaving uncertainty about how to guide prescription in this specific subgroup. On these premises, this multidisciplinary consensus document explains why it would be useful to integrate the clinical evaluation performed through comprehensive geriatric assessment to gather further elements to guide prescription of direct oral anticoagulants in such a high-risk group of patients.

Major bleeding with apixaban in atrial fibrillation: patient characteristics, management, and outcomes

OBJECTIVES

To identify patient characteristics, bleed management, and bleed outcomes in patients experiencing an apixaban major bleeding event and to identify opportunities to improve the safe use of apixaban.

METHODS

This retrospective single health-system study identified apixaban patients experiencing a major bleeding event between January 2013 and May 2016 through electronic medical record review. Patient characteristics, bleed management, and outcomes were extracted in those with a confirmed major bleed assessed by the International Society on Thrombosis and Haemostasis criteria.

RESULTS

Fifty major bleeding events occurred in 49 patients (79 ± 9.8 years). Patient characteristics included history of hypertension (94%), anemia (68%), and concomitant antiplatelet use (68%). Gastrointestinal bleeding occurred in 72% of patients and intracranial hemorrhage in 14% of patients. Packed red blood cells (PRBCs) were utilized in 82% of patients and reversal agents were administered to 6% of patients. Mortality during the hospital admission for the bleed was 0%. Anticoagulation was held at discharge in 64% of patients and remained held at 30 days in the majority of patients. Of those on concurrent aspirin therapy, an appropriate indication was not found in 64.7% of patients.

CONCLUSIONS

Patients with major bleeding were elderly and frequently on inappropriate concomitant antiplatelet therapy. The majority of patients were managed with PRBC transfusion. More than half of patients had anticoagulation therapy held at discharge. Concerns with prescribing and patient management were identified leading to recommendations for improving the safe use of apixaban therapy.