Evidence-based cardiology in hemodialysis patients

Abstract

Cardiac events are the major cause of death in hemodialysis patients. Because of the paucity of randomized clinical trials (RCTs) in hemodialysis patients, most cardiovascular therapies in this population are based on observational studies or results extrapolated from studies that excluded hemodialysis patients. However, associations discovered in observational studies do not prove causality, and these studies often report surrogate outcomes rather than clinical end points. Furthermore, interventions that show effectiveness in the general population may have drastically different outcomes and side effect profiles in hemodialysis patients. This review discusses the results of RCTs undertaken recently to evaluate cardiovascular therapies in hemodialysis patients and emphasizes clinically relevant outcomes. Although some interventions have produced similar outcomes in hemodialysis patients and the general population, others have not, suggesting that the management of cardiovascular disease in hemodialysis patients may require strategies that differ from the best practice guidelines applied to general population.

Figures

Figure 1.

Hemodialysis patients represent a tiny subset of all patients with heart disease. Overlap between heart disease and hemodialysis (HD). In the United States, there are about 27 million patients with cardiac disease and about 400,000 HD patients. Only ∼2% of the patients with heart disease are on HD, whereas ∼80% of HD patients have cardiac disease. Most of the cardiovascular therapies used in HD patients are extrapolated from RCTs that specifically excluded patients with kidney disease.

Figure 2.

The relative risks and benefits of anticoagulation for atrial fibrillation vary between hemodialysis patients and patients with normal kidney function. Risk benefit of anticoagulation in patients with atrial fibrillation. In patients with normal renal function and atrial fibrillation, the benefit of warfarin in preventing strokes exceeds the additional risk of major hemorrhage. In hemodialysis patients, the benefit of warfarin in prevention of strokes is uncertain, whereas there is a substantial risk of major hemorrhage. Thus, it is not clear that the benefit outweighs the risk in hemodialysis patients.