Cardiovascular Events and Mortality in Patients on Hemodialysis: The Prognostic Value of the CHA2DS2-VASc Score.

ABSTRACT

Background and Objectives: Cardiovascular events are the major cause of morbidity and mortality in patients on hemodialysis (HD). Identifying risk factors can help in the effort to reduce cardiovascular risk and improve life expectancy. The objective of this study was to evaluate the ability of the CHA2DS2-VASc score-the risk index of stroke in atrial fibrillation (AF)-to predict strokes, major cardiovascular events, and mortality in patients with end-stage kidney disease. Materials and Methods: The CHA2DS2-VASc and HAS-BLED scores (the bleeding risk from the use of anticoagulation in AF) were calculated in 237 HD patients, 99 women with a median age of 76 (15) years, at the time they commenced HD. The scores' ability to predict long term cardiovascular morbidity and mortality was estimated, both in those with and without AF. Among the exclusion criteria were the change of dialysis method or loss of follow-up, HD due to acute renal failure, and incompliance with medical instructions, thus the sample is not representative of a broader population. Results: The CHA2DS2-VASc score was higher in AF (n = 69) compared to non-AF (n = 168) patients, 5 (2.5) vs. 4 (2), p < 0.0001, respectively. An increased CHA2DS2-VASc score was correlated with cardiovascular events, namely, heart failure (p = 0.007, p = 0.024), stroke (p < 0.0001, p < 0.0001), and risk of all-cause mortality (p < 0.0001, p < 0.0001) in AF and non-AF groups, respectively. The C statistics indicated that the referred score showed modest discrimination in AF and non-AF patients on HD for heart failure, stroke, and all-cause mortality, however for cardiovascular mortality this was found only in the AF group. Conclusions: An increased CHA2DS2-VASc score at the time of HD initiation can predict strokes, heart failure, and all-cause mortality in HD patients independent of the presence of AF. The risk of cardiovascular mortality could only be predicted in patients with AF.