Join more than 1.500 of your peers to stay up to date with the latest in thrombosis.
Sign up now!
This website is intended to provide information to an international audience outside the USA and UK
Think about the following clinical situation:
Because Alex is a candidate for non-vitamin K antagonist oral anticoagulant (NOAC) treatment, his renal function was tested to check whether he would require dose reduction and, while his estimated glomerular filtration rate indicates mild renal impairment, it might not be considered severe enough to substantially worsen his prognosis or require special management.
Given this, why should you consider renal impairment at all?
AF is associated with an increased risk of a progressive decline in renal function for all patients and, once they have renal dysfunction, patients with AF are much more likely to progress to end-stage renal disease than those without.1-3
Renal function also declines naturally with age, meaning that there are unlikely to be improvements when a patient has reached the stage of impaired function.4
Once renal function has been lost, it can rarely be replaced.5
Further compounding the issue, the rate of renal function decline doubles in patients with diabetes.6 This is a significant complication because diabetes is also a common co-morbidity of AF.7 Given that Alex will soon be retiring from a relatively active job, and the known risk factors associated with his lifestyle, type II diabetes is likely to be a concern in the near future.
Once a patient with AF develops renal disease, their risk of stroke/systemic embolism (SE) increases by 50%, and the chance that they will have a bleeding event doubles.8 Therefore, it is of utmost importance to slow or prevent the development and progression of renal disease in a patient like Alex. Further information on the burden of renal impairment in AF can be found here.
The interaction of AF, existing renal impairment and diabetes increases the risk of worsening renal function and stroke/SE.1,2,6,8,9
Each of the currently available NOACs (apixaban, dabigatran, edoxaban and rivaroxaban) have demonstrated efficacy and safety in patients with AF,10-13 and these results were unaffected by the presence of renal impairment.14-17 There is also evidence that some NOACs may be associated with a reduced risk of adverse renal outcomes compared with vitamin K antagonists (VKAs).18,19
Further encouraging data were found in a subset of patients with AF who were at increased risk of stroke/SE due to a combination of impaired renal function and diabetes. The NOACs continued to demonstrate comparable efficacy and safety compared with VKAs in this group,20,21 with evidence indicating that the NOACs may also have preserved renal function compared with VKAs.20
The 2019 update to the American Heart Association/American College of Cardiology/Heart Rhythm Society guidelines acknowledges that the NOACs, particularly rivaroxaban and dabigatran, may be associated with a lower risk of adverse renal outcomes than VKAs in patients with AF.22 When stroke/SE prevention, risk of bleeding and renal preservation are considered in totality, the NOACs present an appealing treatment option for those with AF.
AF is linked to a range of co-morbidities, and it is important that clinicians consider not just those presenting now, but also those which may potentially occur in the future. Of these, it is crucial to consider the patient’s kidneys, not only due to the negative interplay between AF, renal dysfunction and diabetes, but because patients will not regain renal function once it is lost. Preservation is therefore key.
Patients like Alex are typical of those seen daily in clinical practice. While Alex’s presentation is common, it is still important that the full range of disease factors are considered when treating him. While there are no current concerns with Alex’s renal function, careful treatment now could help to ensure that this remains the case.