Canadian Nephrologist Views Regarding Stroke and Systemic Embolism Prevention in Dialysis Patients With Nonvalvular Atrial Fibrillation: A Survey

Stroke Subtype Among Individuals With Chronic Kidney Disease

Background

It is widely accepted that there is a stepwise increase in the risk of acute ischemic stroke with chronic kidney disease (CKD). However, whether the risk of specific ischemic stroke subtypes varies with CKD remains unclear.

Objective

To assess the association between ischemic stroke subtypes (cardioembolic, arterial, lacunar, and other) classified using the Trial of ORG 10172 in Acute Stroke Treatment (TOAST) and CKD stage.

Design

retrospective cohort study.

Setting

Ontario, Canada.

Patients

A total of 17 434 adults with an acute ischemic stroke in Ontario, Canada between April 1, 2002 and March 31, 2013, with an estimated glomerular filtration rate (eGFR) measurement or receipt of maintenance dialysis captured in a stroke registry were included.

Measurements

Kidney function categorized as an eGFR of ≥60, 30-59, <30 mL/min/1.73 m2, or maintenance dialysis. Ischemic stroke classified by TOAST included arterial, cardioembolic, lacunar, and other (dissection, prothrombotic state, cortical vein/sinus thrombosis, and vasculitis) types of strokes.

Methods

Adjusted regression models.

Results

In our cohort, 58.9% had an eGFR of ≥60, 34.7% an eGFR of 30-59, 6.0% an eGFR of <30 and 0.5% were on maintenance dialysis (mean age of 73 years; 48% women). Cardioembolic stroke was more common in patients with non-dialysis-dependant CKD (eGFR 30-59: 50.4%, adjusted odds ratio [OR] 1.20, 95% confidence interval [CI]: 1.02, 1.44; eGFR<30: 50.6%, OR 1.21, 95% CI: 1.02, 1.44), whereas lacunar stroke was less common (eGFR 30-59: 22.7% OR 0.85, 95% CI: 0.77, 0.93; eGFR <30: 0.73, 95% CI: 0.61, 0.88) compared with those with an eGFR ≥60. In stratified analyses by age and CKD, lacunar strokes were more frequent in those aged less than 65 years, whereas cardioembolic was higher in those aged 65 years and above.

Limitations

TOAST classification was not captured for all patients.

Conclusion

Non-dialysis CKD was associated with a higher risk of cardioembolic stroke, whereas an eGFR ≥60 mL/min/1.73 m2 was associated with a higher risk of lacunar stroke. Detailed stroke subtyping in CKD may therefore provide mechanistic insights and refocus treatment strategies in this high-risk population.

[Atrial Fibrillation in Patients on Dialysis Therapy: Epidemiology, Prognosis and Choice of Anticoagulant Therapy]

The review presents data on the prevalence of atrial fibrillation in patients on dialysis therapy. It is shown that dialysis-dependent patients with non-valve atrial fibrillation prognosis is extremely unfavorable, significantly increased risk of death due to both ischemic and hemorrhagic complications. Scales to assess the risk of thromboembolic and hemorrhagic complications in patients with atrial fibrillation on program dialysis are not validated. The lack of data from randomized clinical trials makes it much more difficult to choose anticoagulant therapy in patients with terminal stage of chronic kidney disease on dialysis who have undergone kidney transplantation. Therefore, the need for anticoagulant therapy and the choice of drugs in patients in this category should be made on the basis of a personalized multidisciplinary approach, taking into account comorbid pathology and the patient's preferences.

Anticoagulation in Patients With Advanced Chronic Kidney Disease: Walking the Fine Line Between Benefit and Harm

Chronic kidney disease affects more than 3 million Canadians and is highly associated with cardiovascular diseases that require anticoagulation, such as atrial fibrillation and venous thromboembolism. Patients with chronic kidney disease are at a problematic crossroads; they are at high risk of thrombotic conditions requiring anticoagulation and bleeding complications due to anticoagulation. The limited high-quality clinical evidence to guide decision-making in this area further compounds the dilemma. In this review, we discuss the physiology and epidemiology of bleeding and thrombosis in patients with kidney disease. We specifically focus on patients with advanced kidney disease (estimated glomerular filtration rate ≤ 30 mL/min) or who are receiving dialysis and focus on the nephrologist perspective regarding these issues. We summarize the existing evidence for anticoagulation use in the prevention of stroke with atrial fibrillation and provide practical clinical recommendations for considering anticoagulation use in this population. Last, we examine specific scenarios such as the use of a glomerular filtration rate estimating equation and dosing, the use of existing prediction tools for stroke and hemorrhage risk, current patterns of anticoagulation use (including during the dialysis procedure), and vascular calcification with vitamin K antagonist use in patients with chronic kidney disease.