Dialysis-induced hypotension is associated with impaired aortic elasticity in patients undergoing chronic hemodialysis

Abstract

The pathogenesis of dialysis-induced hypotension (DIH) is multifactorial and may include increased aortic stiffness. This study was undertaken to determine aortic elastic properties in patients undergoing hemodialysis with and without DIH, and to assess the effects of DIH on mortality. Aortic stiffness and left ventricular functions were evaluated in 70 patients undergoing hemodialysis with (n=34) and without DIH (n=36). We also evaluated total mortality at 36 months. Patients with DIH in comparison with patients without DIH, had lower aortic strain (5.0+/-3.8 vs. 7.8+/-3.0%, P<0.005) and distensibility (2.3+/-1.9 vs. 3.2+/-1.7 cm2/dyn/10(3), P<0.01). In univariate analysis, age, aortic stiffness and left ventricular systolic dysfunction, and coronary artery disease were also found to be the main factors associated with DIH. On multivariate logistic regression analysis, aortic distensibility [odds ratio (OR): 0.61; 95% confidence interval (95% CI): 0.40-0.93; P=0.01] and the coronary artery disease (OR: 6.46; 95% CI: 1.62-25.73; P=0.009) remained as significant variables associated with DIH. During follow-up period, 12 out of 34 patients with DIH died compared with 4 out of 36 patients without DIH (log rank, P=0.02). Our data suggest that DIH is strongly associated with increased aortic stiffness and poor outcome. Larger long-term follow-up studies, however, investigating whether the DIH plays a surrogate or causative role on mortality in patients undergoing hemodialysis should be designed.