Effect of Warfarin on Ischemic Stroke, Bleeding, and Mortality in Patients with Atrial Fibrillation Receiving Peritoneal Dialysis

Background There is limited information on the risks and benefits of anticoagulation in patients with atrial fibrillation receiving peritoneal dialysis. Objective The aim was to determine the risk of mortality, ischemic stroke, and bleeding associated with warfarin use in patients with atrial fibrillation receiving peritoneal dialysis. Patients and methods This is a retrospective observational study of a multi-ethnic cohort of patients with atrial fibrillation receiving peritoneal dialysis in the United States. Using a dialysis registry, we identified 476 patients with atrial fibrillation receiving peritoneal dialysis. Among these patients, 115 (24%) were treated with warfarin. Cox proportional hazard models were used to compare risks of mortality, ischemic stroke and bleeding between the groups. Results Compared to untreated patients, patients receiving warfarin were older (67.3 +/- 10.8 vs 62.9 +/- 13.3 years) and more likely to be white (42% vs 31%). Prevalence of comorbidities including hypertension, hyperlipidemia, diabetes, heart failure, and prior ischemic stroke were similar between the two groups. All cause mortality rates were 19.9 per 100 person-years in the warfarin group and 21.0 per 100 person-years in the untreated group. There was no difference between groups in the risk of mortality [hazard ratio (HR) 0.8, 95% confidence interval (CI) 0.53-1.2, p = 0.28], ischemic stroke (HR 2.3, 95% CI 0.94-5.4, p = 0.07), hemorrhagic stroke (HR 2.0, 95% CI 0.32-12.8, p = 0.46), gastrointestinal bleeding (HR 0.92, 95% CI 0.39-2.2, p = 0.86), or any bleeding (HR 1.2, 95% 0.60-2.3, p = 0.65). Even in the subgroup of patients with > 70% time in therapeutic range, no association was seen between warfarin treatment and mortality. Conclusion There is no significant association between warfarin treatment with risks of mortality, ischemic stroke or bleeding in patients with atrial fibrillation receiving peritoneal dialysis.