More Evidence on an Abominable Pairing

In the past 5 years we have experienced a surge in scientific activity related to exploring various aspects linking atrial fibrillation and kidney disease. Previously an understudied topic with available findings derived mostly from small and underpowered samples that were often of limited generalizability, important insights have now been made in large and mostly generalizable cohorts. First, these findings included the realization that the prevalence of atrial fibrillation increased monotonically with impaired kidney function, both and independently, with reduced estimated glomerular filtration rate (eGFR) and with increased urine albumin excretion.1 Patients with end-stage renal disease requiring dialysis had a particularly high prevalence of diagnosed atrial fibrillation exceeding 10%, with >17% of those older than 65 years of age being diagnosed with this most common of arrhythmias.2 Then, not surprisingly, it was also found that the incidence of atrial fibrillation increased with reduced kidney function,3 again with older patients initiating dialysis for end-stage renal disease in the United States having a particularly high incidence at 148 new cases diagnosed per 1000 person-years of observation.4 Outcomes in patients with atrial fibrillation and kidney disease were found to be particularly poor, with dialysis patients having been diagnosed with atrial fibrillation experiencing a 1-year mortality of almost 40%, twice the rate of otherwise similar patients without atrial fibrillation.2Article see p 569 These epidemiological observations raised questions about the most appropriate treatment strategies for patients with both atrial fibrillation and advanced kidney disease. Although oral anticoagulation is generally the recommended secondary prevention for patients with atrial fibrillation, patients with advanced kidney disease have both higher bleeding risks as well as elevated risks for ischemic stroke. The benefit–risk relationship of oral anticoagulation in the population with advanced kidney disease remains ill defined, particularly among those with end-stage renal disease.5 …