Incidence of Stroke among Chronic Hemodialysis Patients with Nonrheumatic Atrial Fibrillation

Abstract

In general, nonrheumatic atrial fibrillation is associated with a high risk of stroke. However, its impact on stroke in the setting of chronic hemodialysis treatment is insufficiently addressed in the literature. We assessed the incidence of stroke among 430 chronic hemodialysis patients and the impact of atrial fibrillation and various other potential risk factors on stroke in a retrospective study covering 1,111.16 patient-years. The overall incidence of stroke was 3.78/100 patient-years. Among patients with chronic atrial fibrillation without any antithrombotic therapy besides regular dialysis anticoagulation, the stroke incidence was 1.0/100 patient-years and did not differ statistically significantly from the rate among patients without this arrhythmia, in whom the incidence was 2.8/100 patient-years (p = 0.220). Conversely, the overall rate of stroke incidence per 100 patient-years was statistically significantly higher in patients with diabetic nephropathy (6.46, p = 0.0036), age >65 years (5.90, p = 0.0001), moderate to severe hypertension (6.8, p = 0.0017), weight gain of >2 kg between dialyses as a marker of poor patient compliance (6.47, p = 0.0433), and antithrombotic therapy with salicylates or warfarin (8.33, p = 0.0002), as compared with corresponding groups without these risk factors. Our data suggest that in contrast to other risk factors nonrheumatic atrial fibrillation in itself is not associated with an increased risk of stroke in patients on maintenance hemodialysis treatment.

Warfarin Use Associates with Increased Risk for Stroke in Hemodialysis Patients with Atrial Fibrillation

“…Stroke rates in warfarin users were statistically no different from rates in nonwarfarin users in a study of patients who had atrial fibrillation and were on dialysis 36 (n ϭ 61). Another study found no difference (P ϭ 0.4) in the incidence of stroke when comparing an "undertreated" population (24% prevalence of warfarin use in patients with atrial fibrillation; n ϭ 127) with patients without atrial fibrillation (n ϭ 349) in the same cohort.…”

“…34,35 Taken together, warfarin use in dialysis patients may confer additional risk that is not appreciated in patients without renal failure. 2,36 Given the paucity of clinical studies of patients with ESRD, it is currently unresolved whether accepted therapeutic interventions for atrial fibrillation 4 can also be applied to patients who are on dialysis. 2,37 Consequently, we conducted a retrospective cohort study to assess the overall risk-benefit ratio of anticoagulation and antiplatelet therapy in this specific population.…”

Major Bleeding in Hemodialysis Patients

“…For example, in patients with AF, the consequence of a cerebrovascular accident may be considerable. The data pertaining to AF in the HD population is limited to two observational cohort studies, and these provide conflicting estimates of stroke risk (18,19). Half of warfarin-associated major bleeding episodes in this study were sustained by patients who were taking the medication for access preservation.…”

Stroke and the “Stroke Belt” in Dialysis

“…However, the potential role of other traditional risk factors is somewhat unclear. Hypertension, for example, has been associated with stroke in some 15 but not all 18 studies, and even the findings on the role of AF are discordant, 17,[19][20][21] although the most comprehensive study to date reported that, in the setting of AF, dialysis patients had a 1.8-fold increased risk of stroke compared with non-dialysis-dependent individuals. 22 Such discrepancies in the literature suggested that even basic relationships between common comorbid conditions and stroke risk are not fully understood in the dialysis population.…”