Warfarin for atrial fibrillation does not worsen outcomes for patients with kidney disease

Although some research has suggested that the use of the anticoagulant warfarin for atrial fibrillation among patients with chronic kidney disease would increase the risk of death or stroke, a study that included more than 24,000 patients found a lower l-year risk of the combined outcomes of death, heart attack or stroke without a higher risk of bleeding, according to a study in the March 5 issue of JAMA. Juan Jesus Carrero, Ph.D., of the Karolinska Institutet, Stockholm, and colleagues examined outcomes associated with warfarin treatment in relation to kidney function among patients with established cardiovascular disease and atrial fibrillation. Using data from a Swedish registry, the study included survivors of a heart attack with atrial fibrillation and known measures of serum creatinine (n = 24,317; a substance used to measure kidney function), including 21.8 percent who were prescribed warfarin at discharge.

About 52 percent of patients had moderate chronic kidney disease (CKD) or worse. The researchers found that warfarin treatment was associated with a lower l-year risk of a composite of the outcomes of death, heart attack, and ischemic stroke without a higher risk of bleeding. This association was observed in patients with moderate, severe, or end-stage CKD. The number of patients who developed the composite outcome, bleeding events, and the total of these 2 outcomes increased with the worsening of CKD categories, as did the rate at which these events occurred.

This work was supported by a grant from the Swedish Foundation for Strategic Research.