Among patients with atrial fibrillation and dialysis-dependent end-stage renal disease, apixaban was associated with lower risk for bleeding than warfarin, researchers reported.
In a sensitivity analysis, the standard 5-mg twice-daily dose of apixaban (Eliquis, Bristol-Myers Squibb/Pfizer) was also associated with lower risk for thromboembolism and mortality than warfarin in this population.
“These are the first data to show that apixaban is potentially safer than warfarin in dialysis patients with atrial fibrillation,” Konstantinos C. Siontis, MD, who at the time of the study was a cardiovascular fellow at Frankel Cardiovascular Center, Michigan Medicine, University of Michigan, and is now affiliated with the department of cardiovascular medicine at Mayo Clinic, said in a press release. “We found patients on apixaban had a significantly lower risk of major bleeding with no difference in stroke, which is what we try to prevent by prescribing these anticoagulants.”
Siontis and colleagues conducted a retrospective cohort study of 25,523 patients (mean age, 68 years; 46% women) who were Medicare beneficiaries included in the United States Renal Data System. Of the cohort, 2,351 patients were taking apixaban and the rest were taking warfarin for stroke prevention due to AF. The 2,351 patients taking apixaban were matched on a 1:3 basis to 7,053 patients taking warfarin based on propensity score.
Outcomes of interest included survival free from stroke or systemic embolism, major bleeding, gastrointestinal bleeding, intracranial bleeding and mortality.
Siontis and colleagues found no significant differences between the groups in stroke/systemic embolism (HR = 0.88; 95% CI, 0.69-1.12), but the apixaban group had lower risk for major bleeding (HR = 0.72; 95% CI, 0.59-0.87).
There were no differences in risk for intracranial bleeding (HR = 0.79; 95% CI, 0.49-1.26), but there was a trend favoring apixaban in risk for gastrointestinal bleeding (HR = 0.86; 95% CI, 0.72-1.02) and mortality (HR = 0.85; 95% CI, 0.71-1.01), according to the researchers.
In sensitivity analyses, the researchers compared apixaban 5 mg twice daily with apixaban 2.5 mg twice daily and warfarin. They found apixaban 5 mg twice daily conferred lower risk for stroke/systemic embolism (HR vs. apixaban 2.5 mg twice daily = 0.61; 95% CI, 0.37-0.98; HR vs. warfarin = 0.64; 95% CI, 0.42-0.97) and death (HR vs. apixaban 2.5 mg twice daily = 0.64; 95% CI, 0.45-0.92; HR vs. warfarin = 0.63; 95% CI, 0.46-0.85).
“It’s useful for clinicians to have this information now as we are waiting for results of important randomized trials that are underway and compare warfarin to apixaban in dialysis patients,” Siontis said in the release. “The combination of dialysis with atrial fibrillation is a difficult one, but as we learn more from real-world data and clinical trials, we are hopeful that the decision-making will be better informed in the near future to the benefit of these patients.” – by Erik Swain
Disclosures: The authors report no relevant financial disclosures.