Author + information
- Patricio A. Pazmiño, PhD, MD∗ ()
- ↵∗Nephrology, Internal Medicine & Hypertension (NIH) Center, 1701 N. Mesa, El Paso, Texas 779902-3503
I read with interest the paper by Yao et al. (1), who investigated the novel oral anticoagulants (NOACs) in 14,865 patients with atrial fibrillation and renal dysfunction. They concluded that the dosing patterns prescribed for the NOACs were often inconsistent with drug labeling or with the renal dose specified by the U.S. Food and Drug Administration (1). Similar findings were noted by Steinberg et al. from data from the ORBIT-AF II Registry (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation), which concluded that almost 1 in 8 U.S. patients in the community received NOAC doses inconsistent with labeling (2). Overdosing and under dosing of NOACs are associated with increased risk for adverse events (1–3).
Yao et al. (1) concluded that “better clinical decision support tools are needed to guide NOAC dosing in patient with renal impairment,” and I would like to bring their attention to a renal risk stratification tool based on the stage of chronic kidney disease (CKD) that helps in the dosing of NOACs in patient with CKD (3–5).
Table 1 summarizes doses and indications for NOACs and includes the recently approved factor Xa inhibitor Betrixaban (Bevyxxa, Portola, San Francisco, California). This is indicated for prophylaxis of venous thromboembolism in adults hospitalized for acute medical illness at risk for thromboembolic complications. The initial dose is 160 mg orally, which is then continued at 80 mg orally daily for 35 to 42 days. If no or mild-to-moderate renal impairment is noted, or if patients have stage 1, 2, or 3 CKD, no dose adjustment is needed. If the patient has severe renal impairment or stage 4 CKD, or if the patient is using permeability glycoprotein inhibitors, the initial dose is 80 mg, then 40 mg orally daily for 35 to 42 days. As shown in Table 1, in patients with renal failure or stage 5 CKD, Bevyxxa should be avoided.
The NOACs are coming of age, but caution and renal risk stratification are required. The renal risk stratification guideline avoids calculations of creatinine clearance because of reported problems (3) and uses instead the determination of the estimated glomerular filtration rate from the Modification of Diet in Renal Disease formula and CKD stage. The Modification of Diet in Renal Disease is widely used by most U.S. laboratories and includes 4 variables: serum creatinine, age, sex, and race. The renal risk stratification guideline has not been validated for clinical use. However, the actual dosing is the same for equivalent stages of renal dysfunction based on the current NOACs prescribing information.
Please note: Dr. Pazmiño has reported that he has no relationships relevant to the contents of this paper to disclose.
- 2017 American College of Cardiology Foundation
- Yao K.,
- Shah N.D.,
- Sangaralingham L.R.,
- Gersh B.J.,
- Noseworthy P.A.
- Steinberg B.A.,
- Shrader P.,
- Thomas L.,
- et al.
- Pazmiño P.A.
- Pazmiño P.A.
- Pazmiño P.A.