Published: 05-03-2014 07:15 | Updated: 05-03-2014 21:46

Warfarin also beneficial in atrial fibrillation patients with kidney disease

Warfarin treatment is associated with better prognosis in atrial fibrillation patients with kidney disease, according to a prospective observational study from Karolinska Institutet. The findings are published in the March issue of JAMA.

Patients with concomitant atrial fibrillation and reduced renal function are increasingly common, since the conditions share several risk factors and also promote one another. These individuals are at a markedly increased risk of bleeding and ischemic stroke. Although they have a clear indication for anticoagulant therapy, several observational studies examining the effectiveness and safety of warfarin in severe renal disease have suggested that warfarin treatment may increase the risk of death and stroke in such patients. Today, there is no clear recommendation on how to treat these high-risk individuals.

Scientists from Karolinska Institutet have used the SWEDEHEART registry to study more than 24 000 swedes with atrial fibrillation who survived a myocardial infarction during the period 2003–2010. Estimated glomerular filtration rate (eGFR) allowed classification of chronic kidney disease severity. More than half (51.7 per cent) were considered to have chronic kidney disease, and over 5 000 (21.8 per cent) of the patients were treated with warfarin at hospital discharge.

The scientists studied outcomes associated with warfarin treatment in individuals with different stages of kidney disease. They found that in all kidney disease stages considered, warfarin treatment was associated with a reduced 1-year risk of the composite outcome of death, myocardial infarction and stroke. The risk of bleeding was not increased. Warfarin treatment conveyed the same benefit in patients with chronic kidney disease than in patients without.

“Our study deals with a large group of currently undertreated patients,and indicates that individuals with atrial fibrillation and renal disease not requiring dialysis can also benefit from warfarin therapy and should not be denied this treatment option”, says first study author Juan Jesús Carrero at the Department of Clinical Science, Intervention and Technology at Karolinska Institutet.

The research was supported by a grant from the Swedish Foundation for Strategic Research and the Swedish Research Council.

Text: Karin Söderlund Leifler


Warfarin, Kidney Dysfunction, and Outcomes Following Acute Myocordial Infarction in Patients With Atrial Fibrillation
Juan Jesus Carrero-Roig, Marie Evans, Karolina Szummer, Jonas Spaak, Lars Lindhagen, Robert Edfors, Peter Stenvinkel, Stefan H Jacobson, Tomas Jernberg
JAMA, online 4 March 2014