Biomarker Profiling in Stage 5 Chronic Kidney Disease Identifies the Relationship between Angiopoietin-2 and Atrial Fibrillation

Abstract

Atrial fibrillation (AF) is prevalent in nearly 27% of patients with stage 5 chronic kidney disease on hemodialysis (CKD5-HD), suggesting a strong association between these 2 pathologies. It is hypothesized that the relationship between these 2 diseases may be mediated by inflammation. Angiopoietin-2 (Ang-2), a pro-inflammatory biomarker of endothelial instability, inflammation, and vascular remodeling, is elevated in CKD5-HD and AF, yet has not been evaluated in patients with concomitant AF and CKD5-HD. The aim of this study is to analyze circulating levels of inflammatory and thrombotic biomarkers in patients with concomitant AF and CKD5-HD. Plasma levels of Ang-2 were measured via sandwich enzyme-linked immunosorbent assay method in CKD5-HD patients (n = 96), patients with AF (n = 38), and controls (n = 50). Angiopoietin-2 was markedly elevated in CKD5-HD with comorbid AF as compared to CKD5-HD alone, and AF alone, respectively (13.05 ± 1.56 vs 9.57 ± 0.71 ng/mL; P = .00169; vs 2.48 ± 0.57 ng/mL; P < .0001). The results of this study suggest an additive effect of Ang-2 with coexistence of AF and CKD5-HD, which may be useful in the detection of AF within this patient population.

Keywords: angiopoietin-2; atrial fibrillation; biomarkers; chronic kidney disease; hemodialysis; inflammation.

Figure 1.

Comparison of Ang-2 levels between controls, AF, CKD5-HD (+)AF, and CKD5-HD (−)AF. Mean levels were 1.87 ± 0.15 ng/mL for controls, 2.48 ± 0.57 ng/mL for AF, 13.05 ± 1.56 ng/mL for CKD5-HD (+)AF, and 9.57 ± 0.71 ng/mL for CKD5-HD (−)AF. AF indicates atrial fibrillation; Ang-2, angiopoietin-2; CKD5-HD, stage 5 chronic kidney disease on hemodialysis.